{"id":1871,"date":"2026-08-16T09:24:39","date_gmt":"2026-08-16T09:24:39","guid":{"rendered":"https:\/\/haktak.com\/?p=1871"},"modified":"2026-08-16T09:33:52","modified_gmt":"2026-08-16T09:33:52","slug":"copper-shim-vs-thermal-pad","status":"publish","type":"post","link":"https:\/\/haktak.com\/vi\/copper-shim-vs-thermal-pad\/","title":{"rendered":"Mi\u1ebfng \u0111\u1ec7m \u0111\u1ed3ng (Copper Shim) v\u00e0 Mi\u1ebfng t\u1ea3n nhi\u1ec7t (Thermal Pad): Nh\u1eefng \u0111i\u1ec3m kh\u00e1c bi\u1ec7t ch\u00ednh"},"content":{"rendered":"<div class=\"product\"><div class=\"product\">\n<p class=\"wp-block-paragraph\">L\u00e1 \u0111\u1ed3ng kh\u00f4ng m\u1eb7c nhi\u00ean t\u1ed1t h\u01a1n mi\u1ebfng \u0111\u1ec7m nhi\u1ec7t, d\u00f9 \u0111\u1ed3ng c\u00f3 \u0111\u1ed9 d\u1eabn nhi\u1ec7t c\u1ee7a v\u1eadt li\u1ec7u nguy\u00ean kh\u1ed1i cao h\u01a1n nhi\u1ec1u. \u0110\u1ed3ng c\u1ee9ng. Mi\u1ebfng \u0111\u1ec7m nhi\u1ec7t c\u00f3 kh\u1ea3 n\u0103ng bi\u1ebfn d\u1ea1ng. S\u1ef1 kh\u00e1c bi\u1ec7t c\u01a1 h\u1ecdc \u0111\u01a1n gi\u1ea3n n\u00e0y l\u00e0m thay \u0111\u1ed5i c\u00e1ch m\u1ed7i v\u1eadt li\u1ec7u ti\u1ebfp x\u00fac v\u1edbi ngu\u1ed3n nhi\u1ec7t, b\u00f9 tr\u1eeb bi\u1ebfn \u0111\u1ed9ng khe h\u1edf, t\u1ea1o t\u1ea3i l\u00ean c\u00e1c linh ki\u1ec7n d\u1ec5 h\u1ecfng v\u00e0 ch\u1ecbu t\u00e1c \u0111\u1ed9ng trong qu\u00e1 tr\u00ecnh l\u1eafp r\u00e1p.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Trong m\u1ed9t giao di\u1ec7n ph\u1eb3ng v\u1edbi dung sai \u0111\u01b0\u1ee3c ki\u1ec3m so\u00e1t ch\u1eb7t ch\u1ebd, mi\u1ebfng \u0111\u1ec7m \u0111\u1ed3ng c\u00f3 k\u00edch th\u01b0\u1edbc ph\u00f9 h\u1ee3p, k\u1ebft h\u1ee3p v\u1edbi l\u1edbp v\u1eadt li\u1ec7u giao di\u1ec7n r\u1ea5t m\u1ecfng \u1edf c\u1ea3 hai m\u1eb7t, c\u00f3 th\u1ec3 ho\u1ea1t \u0111\u1ed9ng t\u1ed1t. Trong m\u1ed9t c\u1ee5m l\u1eafp r\u00e1p c\u00f3 chi\u1ec1u cao linh ki\u1ec7n kh\u00f4ng \u0111\u1ed3ng \u0111\u1ec1u, dung sai ch\u01b0a x\u00e1c \u0111\u1ecbnh r\u00f5, rung \u0111\u1ed9ng ho\u1eb7c y\u00eau c\u1ea7u c\u00e1ch ly \u0111i\u1ec7n, mi\u1ebfng \u0111\u1ec7m c\u00f3 kh\u1ea3 n\u0103ng n\u00e9n th\u01b0\u1eddng l\u00e0 l\u1ef1a ch\u1ecdn an to\u00e0n h\u01a1n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">V\u00ec v\u1eady, c\u00e2u h\u1ecfi th\u1ef1c s\u1ef1 kh\u00f4ng ph\u1ea3i l\u00e0: \u201cV\u1eadt li\u1ec7u n\u00e0o c\u00f3 ch\u1ec9 s\u1ed1 W\/mK l\u1edbn h\u01a1n?\u201d m\u00e0 l\u00e0: \u201cH\u1ec7 ti\u1ebfp x\u00fac ho\u00e0n ch\u1ec9nh n\u00e0o t\u1ea1o ra \u0111i\u1ec7n tr\u1edf nhi\u1ec7t th\u1ea5p nh\u1ea5t v\u00e0 \u1ed5n \u0111\u1ecbnh m\u00e0 kh\u00f4ng l\u00e0m h\u1ecfng c\u1ee5m l\u1eafp r\u00e1p?\u201d H\u01b0\u1edbng d\u1eabn n\u00e0y tr\u00ecnh b\u00e0y c\u00e1ch \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh \u0111\u00f3 cho GPU, VRAM, m\u00e1y t\u00ednh x\u00e1ch tay, m\u00f4-\u0111un c\u00f4ng su\u1ea5t, thi\u1ebft b\u1ecb vi\u1ec5n th\u00f4ng v\u00e0 thi\u1ebft b\u1ecb \u0111i\u1ec7n t\u1eed c\u00f4ng nghi\u1ec7p.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Copper Shim vs Thermal Pad: Quick Comparison<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A copper shim favors high conductivity and dimensional stability, while a thermal pad favors conformity, electrical isolation and tolerance absorption. Copper can move heat efficiently through its body, but poor contact on either face can erase that advantage. A pad has lower conductivity, yet it can create more complete contact across rough, tilted or mixed-height surfaces.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Y\u1ebfu t\u1ed1 quy\u1ebft \u0111\u1ecbnh<\/strong><\/td><td><strong>Copper Shim<\/strong><\/td><td><strong>Nhi\u1ec7t <\/strong><strong>Mi\u1ebfng \u0111\u1ec7m<\/strong><\/td><\/tr><tr><td>Bulk conductivity<\/td><td>Very high for suitable copper grades<\/td><td>Lower and formulation-dependent<\/td><\/tr><tr><td>Kh\u1ea3 n\u0103ng th\u00edch \u1ee9ng<\/td><td>Rigid and unable to fill microscopic roughness alone<\/td><td>Compressible and able to follow surface variation<\/td><\/tr><tr><td>Dung sai khe h\u1edf<\/td><td>Needs tightly controlled thickness and geometry<\/td><td>Handles a wider working-gap range<\/td><\/tr><tr><td>Additional TIM<\/td><td>Usually needs a thin interface layer on both faces<\/td><td>Normally serves as the interface layer itself<\/td><\/tr><tr><td>H\u00e0nh vi \u0111i\u1ec7n<\/td><td>Electrically conductive unless separately isolated<\/td><td>Electrically insulating grades are widely available<\/td><\/tr><tr><td>Mechanical load<\/td><td>Transfers displacement and force directly<\/td><td>Cushions variation, depending on hardness and compression<\/td><\/tr><tr><td>Ph\u00f9 h\u1ee3p cho s\u1ea3n xu\u1ea5t<\/td><td>Requires controlled placement and retention<\/td><td>Available as die-cut parts with liners and pull tabs<\/td><\/tr><tr><td>\u1ee8ng d\u1ee5ng ph\u00f9 h\u1ee3p \u0111i\u1ec3n h\u00ecnh nh\u1ea5t<\/td><td>C\u00e1c b\u1ec1 m\u1eb7t ti\u1ebfp x\u00fac ch\u00ednh x\u00e1c, \u1ed5n \u0111\u1ecbnh v\u00e0 ph\u1eb3ng<\/td><td>Khe h\u1edf thay \u0111\u1ed5i, c\u1ee5m linh ki\u1ec7n kh\u00f4ng \u0111\u1ed3ng \u0111\u1ec1u v\u00e0 linh ki\u1ec7n d\u1ec5 h\u01b0 h\u1ecfng<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u00e2y l\u00e0 b\u1ea3ng s\u00e0ng l\u1ecdc, kh\u00f4ng ph\u1ea3i th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt cu\u1ed1i c\u00f9ng. K\u1ebft lu\u1eadn c\u00f3 th\u1ec3 thay \u0111\u1ed5i khi khe h\u1edf th\u1ef1c t\u1ebf, l\u1ef1c k\u1eb9p, \u0111\u1ed9 ho\u00e0n thi\u1ec7n b\u1ec1 m\u1eb7t ho\u1eb7c y\u00eau c\u1ea7u v\u1ec1 \u0111i\u1ec7n \u00e1p thay \u0111\u1ed5i. M\u1ed9t sai s\u1ed1 0.2 mm t\u01b0\u1edfng ch\u1eebng r\u1ea5t nh\u1ecf tr\u00ean b\u1ea3n v\u1ebd c\u00f3 th\u1ec3 \u0111\u1ee7 \u0111\u1ec3 l\u00e0m b\u1ed9 t\u1ea3n nhi\u1ec7t b\u1ecb nh\u1ea5c kh\u1ecfi \u0111\u1ebf b\u00e1n d\u1eabn GPU ho\u1eb7c g\u00e2y qu\u00e1 t\u1ea3i l\u00ean v\u1ecf linh ki\u1ec7n nh\u1edb.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Is a Copper Shim, and What Is a Thermal Pad?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A copper shim is a rigid metal spacer used to bridge a controlled distance in a heat path. A thermal pad is a soft, filled polymer sheet designed to deform and make contact over a range of gaps. Both can conduct heat, but they solve different mechanical problems. Treating them as drop-in substitutes is where many cooling jobs go wrong.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-1024x576.png\" alt=\"What Is a Copper Shim, and What Is a Thermal Pad?\" class=\"wp-image-1873\" srcset=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-1024x576.png 1024w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-300x169.png 300w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-768x432.png 768w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-1536x864.png 1536w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-18x10.png 18w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5-600x338.png 600w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-5.png 1672w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Copper shims are rigid heat-conducting spacers<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A thermal copper shim is usually a thin, flat piece of copper cut or stamped to size. Common choices include C110 copper, oxygen-free copper and nickel-plated copper. The metal may be supplied in precise thicknesses, but its performance also depends on flatness, burr height, surface roughness, oxidation and the way it is held in place.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Copper bridges the visible gap. It does not naturally fill microscopic valleys on a chip, heat spreader or heat sink. Even two parts that look mirror-flat have high points and low points. When a bare shim touches those high points, much of the apparent area can still contain air. That is why copper shim assemblies commonly use a very thin layer of thermal grease, phase-change material or another conformable TIM on both faces.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Those extra layers are part of the design. Their thickness and coverage cannot be ignored. The shim also needs clean edges, enough clearance from nearby components and positive retention so it cannot slide into exposed circuitry.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Thermal pads are compliant gap-filling interfaces<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A thermal pad generally combines a silicone or silicone-free polymer matrix with thermally conductive ceramic filler such as alumina or boron nitride. The balance of polymer, filler and reinforcement controls conductivity, hardness, tack, dielectric behavior, compression set and long-term stability.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When compressed, a pad follows surface texture and component-height variation. It can contact several VRAM packages or MOSFETs even when they do not sit in exactly the same plane. The pad may also provide electrical insulation and vibration cushioning. These are useful jobs that a plain copper plate cannot perform.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C\u00e1c mi\u1ebfng \u0111\u1ec7m \u0111\u01b0\u1ee3c cung c\u1ea5p d\u01b0\u1edbi d\u1ea1ng t\u1ea5m, cu\u1ed9n v\u00e0 chi ti\u1ebft \u0111\u01b0\u1ee3c gia c\u00f4ng theo y\u00eau c\u1ea7u. \u0110\u1ed9 d\u00e0y, \u0111\u1ed9 c\u1ee9ng Shore 00 ho\u1eb7c Shore OO, \u0111\u1eb7c t\u00ednh n\u00e9n\u2013bi\u1ebfn d\u1ea1ng, thi\u1ebft k\u1ebf l\u1edbp l\u00f3t v\u00e0 \u0111\u1ed9 ch\u00ednh x\u00e1c khi \u0111\u1ecbnh v\u1ecb \u0111\u1ec1u r\u1ea5t quan tr\u1ecdng. C\u1ee7a Haktak <a href=\"https:\/\/haktak.com\/vi\/thermal-pads\/\">d\u00f2ng s\u1ea3n ph\u1ea9m mi\u1ebfng \u0111\u1ec7m nhi\u1ec7t<\/a> bao g\u1ed3m c\u00e1c d\u1ea1ng v\u1eadt li\u1ec7u l\u1ea5p \u0111\u1ea7y khe h\u1edf ti\u00eau chu\u1ea9n v\u00e0 theo y\u00eau c\u1ea7u \u1ee9ng d\u1ee5ng cho c\u00e1c c\u1ee5m l\u1eafp r\u00e1p \u0111i\u1ec7n t\u1eed.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">V\u00ec sao W\/mK cao h\u01a1n c\u1ee7a \u0111\u1ed3ng kh\u00f4ng \u0111\u1ed3ng ngh\u0129a v\u1edbi \u0111i\u1ec7n tr\u1edf nhi\u1ec7t giao di\u1ec7n th\u1ea5p h\u01a1n<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-1024x576.png\" alt=\"Why Copper's Higher W\/mK Does Not Automatically Mean Lower Interface Resistance\" class=\"wp-image-1874\" srcset=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-1024x576.png 1024w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-300x169.png 300w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-768x432.png 768w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-1536x864.png 1536w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-18x10.png 18w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6-600x338.png 600w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-6.png 1672w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u1ed9 d\u1eabn nhi\u1ec7t m\u00f4 t\u1ea3 m\u1ee9c \u0111\u1ed9 d\u1ec5 d\u00e0ng truy\u1ec1n nhi\u1ec7t qua m\u1ed9t v\u1eadt li\u1ec7u. Th\u00f4ng s\u1ed1 n\u00e0y kh\u00f4ng m\u00f4 t\u1ea3 to\u00e0n b\u1ed9 m\u1ed1i gh\u00e9p. M\u1ed9t giao di\u1ec7n ho\u1ea1t \u0111\u1ed9ng c\u00f2n bao g\u1ed3m \u0111i\u1ec7n tr\u1edf ti\u1ebfp x\u00fac t\u1ea1i c\u1ea3 hai b\u1ec1 m\u1eb7t. \u0110\u1ed3ng c\u00f3 th\u1ec3 t\u1ea1o ra \u0111\u01b0\u1eddng truy\u1ec1n nhi\u1ec7t r\u1ea5t nhanh qua ph\u1ea7n gi\u1eefa, nh\u01b0ng n\u1ebfu ti\u1ebfp x\u00fac k\u00e9m \u1edf m\u1ed9t trong hai \u0111\u1ea7u, to\u00e0n b\u1ed9 k\u1ebft c\u1ea5u c\u00f3 th\u1ec3 ho\u1ea1t \u0111\u1ed9ng k\u00e9m h\u01a1n m\u1ed9t mi\u1ebfng \u0111\u1ec7m m\u1ec1m h\u01a1n nh\u01b0ng ti\u1ebfp x\u00fac \u0111\u1ea7y \u0111\u1ee7 h\u01a1n.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u00f4 h\u00ecnh \u0111\u01a1n gi\u1ea3n h\u00f3a l\u00e0: <strong>R_total = R_contact 1 + t\/(<\/strong><strong>kA<\/strong><strong>) + R_contact 2<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u00e2y, <strong>t<\/strong> l\u00e0 chi\u1ec1u d\u00e0y v\u1eadt li\u1ec7u, <strong>k<\/strong> l\u00e0 \u0111\u1ed9 d\u1eabn nhi\u1ec7t v\u00e0 <strong>A<\/strong> l\u00e0 di\u1ec7n t\u00edch hi\u1ec7u d\u1ee5ng. Thu\u1eadt ng\u1eef \u1edf gi\u1eefa l\u00e0 \u0111i\u1ec7n tr\u1edf kh\u1ed1i c\u1ee7a v\u1eadt li\u1ec7u. Hai thu\u1eadt ng\u1eef ti\u1ebfp x\u00fac bi\u1ec3u th\u1ecb s\u1ef1 ti\u1ebfp x\u00fac kh\u00f4ng ho\u00e0n h\u1ea3o t\u1ea1i c\u00e1c b\u1ec1 m\u1eb7t c\u1ee7a v\u1eadt li\u1ec7u.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">H\u00e3y h\u00ecnh dung \u0111\u1ed3ng nh\u01b0 m\u1ed9t con \u0111\u01b0\u1eddng cao t\u1ed1c r\u1ed9ng v\u00e0 nhanh. N\u1ebfu x\u1ea3y ra \u00f9n t\u1eafc t\u1ea1i c\u1ea3 hai \u0111\u01b0\u1eddng d\u1eabn v\u00e0o, vi\u1ec7c m\u1edf r\u1ed9ng con \u0111\u01b0\u1eddng \u1edf gi\u1eefa kh\u00f4ng th\u1ec3 gi\u1ea3i quy\u1ebft to\u00e0n b\u1ed9 h\u00e0nh tr\u00ecnh. M\u1ee1 t\u1ea3n nhi\u1ec7t c\u00f3 th\u1ec3 gi\u00fap th\u00f4ng tho\u00e1ng c\u00e1c \u0111\u01b0\u1eddng d\u1eabn n\u00e0y b\u1eb1ng c\u00e1ch l\u1ea5p \u0111\u1ea7y nh\u1eefng kho\u1ea3ng r\u1ed7ng si\u00eau nh\u1ecf, nh\u01b0ng n\u00f3 b\u1ed5 sung th\u00eam m\u1ed9t l\u1edbp v\u1eadt li\u1ec7u v\u00e0 ph\u1ea3i \u0111\u01b0\u1ee3c duy tr\u00ec \u1edf \u0111\u1ed9 d\u00e0y m\u1ecfng. Qu\u00e1 nhi\u1ec1u m\u1ee1 s\u1ebd tr\u1edf th\u00e0nh m\u1ed9t l\u1edbp \u0111i\u1ec7n tr\u1edf kh\u00e1c. Qu\u00e1 \u00edt m\u1ee1 c\u00f3 th\u1ec3 \u0111\u1ec3 l\u1ea1i nh\u1eefng \u0111i\u1ec3m kh\u00f4ng \u0111\u01b0\u1ee3c ph\u1ee7.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110i\u1ec7n tr\u1edf ti\u1ebfp x\u00fac thay \u0111\u1ed5i theo \u0111\u1ed9 nh\u00e1m, \u0111\u1ed9 ph\u1eb3ng, \u00e1p su\u1ea5t, kh\u1ea3 n\u0103ng th\u1ea5m \u01b0\u1edbt c\u1ee7a b\u1ec1 m\u1eb7t v\u00e0 di\u1ec7n t\u00edch ti\u1ebfp x\u00fac th\u1ef1c t\u1ebf. M\u1ed9t mi\u1ebfng \u0111\u1ec7m c\u1ee9ng \u0111\u1eb7t tr\u00ean b\u1ec1 m\u1eb7t h\u01a1i nghi\u00eang c\u00f3 th\u1ec3 ti\u1ebfp x\u00fac m\u1ea1nh \u1edf m\u1ed9t c\u1ea1nh nh\u01b0ng h\u1ea7u nh\u01b0 kh\u00f4ng ti\u1ebfp x\u00fac \u1edf nh\u1eefng v\u1ecb tr\u00ed kh\u00e1c. Mi\u1ebfng \u0111\u1ec7m m\u1ec1m th\u01b0\u1eddng c\u00f3 th\u1ec3 b\u00e1m theo \u0111\u1ed9 nghi\u00eang \u0111\u00f3, m\u1eb7c d\u00f9 mi\u1ebfng \u0111\u1ec7m qu\u00e1 d\u00e0y ho\u1eb7c qu\u00e1 c\u1ee9ng c\u00f3 th\u1ec3 t\u1ef1 g\u00e2y ra v\u1ea5n \u0111\u1ec1 v\u1ec1 \u00e1p su\u1ea5t.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ef1 ph\u00e2n bi\u1ec7t n\u00e0y l\u00e0 l\u00fd do c\u00e1c k\u1ef9 s\u01b0 so s\u00e1nh <a href=\"https:\/\/haktak.com\/vi\/thermal-conductivity-vs-thermal-impedance-tim-selection\/\">\u0111\u1ed9 d\u1eabn nhi\u1ec7t v\u1edbi tr\u1edf kh\u00e1ng nhi\u1ec7t<\/a> thay v\u00ec ch\u1ec9 l\u1ef1a ch\u1ecdn d\u1ef1a tr\u00ean W\/mK. Ph\u01b0\u01a1ng ph\u00e1p ch\u00ednh th\u1ee9c <a href=\"https:\/\/store.astm.org\/d5470-17r24.html\" target=\"_blank\" rel=\"noopener\">ASTM D5470-17(2024)<\/a> \u0111o c\u00e1c \u0111\u1eb7c t\u00ednh truy\u1ec1n nhi\u1ec7t trong c\u00e1c \u0111i\u1ec1u ki\u1ec7n th\u1eed nghi\u1ec7m \u0111\u00e3 quy \u0111\u1ecbnh. C\u1ea7n xem x\u00e9t \u00e1p su\u1ea5t, \u0111\u1ed9 d\u00e0y, c\u00e1ch chu\u1ea9n b\u1ecb m\u1eabu v\u00e0 \u0111\u1eb7c t\u00ednh ti\u1ebfp x\u00fac khi so s\u00e1nh k\u1ebft qu\u1ea3.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">M\u1ed9t ph\u00e9p t\u00ednh minh h\u1ecda ng\u1eafn, kh\u00f4ng ph\u1ea3i cam k\u1ebft v\u1ec1 hi\u1ec7u n\u0103ng<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">H\u00e3y h\u00ecnh dung m\u1ed9t b\u1ec1 m\u1eb7t ti\u1ebfp x\u00fac 20 mm \u00d7 20 mm. So s\u00e1nh m\u1ed9t mi\u1ebfng \u0111\u1ec7m \u0111\u1ed3ng 1 mm \u1edf m\u1ee9c gi\u1ea3 \u0111\u1ecbnh 390 W\/mK v\u1edbi m\u1ed9t t\u1ea5m \u0111\u1ec7m 1 mm \u1edf m\u1ee9c gi\u1ea3 \u0111\u1ecbnh 6 W\/mK. N\u1ebfu ch\u1ec9 t\u00ednh \u0111i\u1ec7n tr\u1edf nhi\u1ec7t kh\u1ed1i, ph\u1ea7n c\u1ee7a \u0111\u1ed3ng th\u1ea5p h\u01a1n nhi\u1ec1u:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Th\u00e0nh ph\u1ea7n \u0111i\u1ec7n tr\u1edf nhi\u1ec7t kh\u1ed1i c\u1ee7a \u0111\u1ed3ng: <strong>0.001 \/ (390 x 0.0004)<\/strong>, about <strong>0.0064 K\/W<\/strong><\/li>\n\n\n\n<li>Pad bulk term: <strong>0.001 \/ (6 x 0.0004)<\/strong>, about <strong>0.417 K\/W<\/strong>\n<ul class=\"wp-block-list\">\n<li><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">That looks decisive. It is not the whole result. The copper assembly still has two copper-to-TIM contacts and two thin interface layers. If the shim tilts, the paste is thick, or clamp pressure is uneven, those contact terms may dominate. The pad may show higher bulk resistance but better real contact.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The numbers above are only a physics illustration. They are not a promised temperature reduction or a product comparison. A useful test has to reproduce the actual thickness, pressure, area, orientation and aging profile.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">The Mechanical Difference Is Often More Important Than the Thermal Difference<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Copper and thermal pads respond very differently to dimensional error. A copper shim transfers its thickness and load almost directly into the assembly. A pad deforms and absorbs some variation. That makes gap tolerance, package strength, PCB bending and clamp pressure central selection criteria, not side notes after a conductivity decision.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Gap tolerance and parallelism<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The thickness printed on a removed pad is not necessarily the working gap. Pads are normally installed under compression. A nominal 1.5 mm pad may have operated at a smaller compressed thickness, and the compression may not have been equal across the part.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Measure the minimum, nominal and maximum assembled gap across several units. Include component-height tolerance, solder thickness, housing flatness, heat-sink tilt, fastener position and thermal expansion. If the gap changes across the interface, one uniform metal shim can become a hard pivot point.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Pressure, package stress and PCB bending<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A rigid shim does not forgive much extra stack height. If it is too thick, it can load an exposed die, VRAM package, BGA solder joints or a thin PCB. It may also prevent the cooler from contacting a neighboring component. This is why a GPU core sometimes becomes hotter after someone &#8220;improves&#8221; the memory interface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Pads absorb variation, but they are not harmless pillows. A hard pad or excessive compression can still create high force. The <a href=\"https:\/\/haktak.com\/vi\/how-compression-affects-thermal-pad-performance\/\">effect of compression on thermal pad performance<\/a> must be balanced against the safe load of packages, solder joints and the board.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">NASA&#8217;s overview of <a href=\"https:\/\/www.nasa.gov\/smallsat-institute\/sst-soa\/thermal-control\/\" target=\"_blank\" rel=\"noopener\">small-spacecraft thermal control<\/a> makes a useful general point: interface conductance depends on contact pressure, and bolted joints do not necessarily create uniform pressure. The same principle applies to a heat sink fixed by screws or spring clips. Torque alone does not prove that every component has good contact.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Electrical isolation and placement safety<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Copper conducts electricity. That may be acceptable on an isolated heat spreader, but it becomes a serious hazard near passives, solder joints, test points and exposed traces. The design must consider creepage, clearance and the possibility of a loose shim moving after shock or service.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An insulating coating or film can reduce electrical risk, but it becomes another layer in the thermal stack. Its dielectric strength, thickness, adhesion and puncture resistance need validation. Where heat transfer and insulation must come from one placed part, <a href=\"https:\/\/haktak.com\/vi\/electrically-insulating-thermal-pads-when-do-you-need-them\/\">c\u00e1c mi\u1ebfng c\u00e1ch nhi\u1ec7t c\u00e1ch \u0111i\u1ec7n b\u1eb1ng \u0111i\u1ec7n<\/a> are often easier to control.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Where a Copper Shim Can Make Sense<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-1024x576.png\" alt=\"Where a Copper Shim Can Make Sense\" class=\"wp-image-1875\" srcset=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-1024x576.png 1024w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-300x169.png 300w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-768x432.png 768w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-1536x864.png 1536w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-18x10.png 18w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7-600x338.png 600w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-7.png 1672w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A copper shim is most defensible when the gap is stable, both surfaces are flat and parallel, clamp load is controlled, and electrical conduction is either acceptable or deliberately isolated. In that environment, the shim behaves as an engineered spacer. It is less convincing when it is used to guess at an unknown gap during a repair.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Controlled heat-spreader interfaces<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A machined assembly with tight dimensional control can make good use of a copper spacer. The design should specify copper grade, thickness tolerance, flatness, edge condition and retention. Very thin interface layers can then address microscopic roughness on both sides.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Nickel plating may be considered where oxidation, repeated handling or surface compatibility matters. Plating changes the surface and should be included in thermal and adhesion testing. It is not simply cosmetic.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Repairing a known mechanical gap<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A laptop, mini PC or embedded device may have a real stand-off problem between a package and its cooler. If measurements show a stable gap, a copper shim can correct that geometry. This is first a mechanical repair, then a thermal change.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Internet reports of large temperature drops can be useful clues, but they are not transferable specifications. The original pad may have been damaged, the cooler may have been poorly seated, or the reported sensor may not represent the hottest location. Copying another user&#8217;s shim thickness without measuring your own unit is a gamble.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Hybrid metal-spreader designs<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A designed copper plate with thin compliant TIM can reduce the amount of low-conductivity material across a larger, well-controlled gap. This can make sense in power electronics and heat-spreader structures.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">What usually does not make sense is an improvised stack of thick pad, loose shim and another thick pad. Every extra layer adds an interface and another tolerance. If the gap is large and irregular, a conformable material or a redesigned spreader is normally easier to validate.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Where a Thermal Pad Is Usually the Better Choice<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-1024x576.png\" alt=\"Where a Thermal Pad Is Usually the Better Choice\" class=\"wp-image-1876\" srcset=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-1024x576.png 1024w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-300x169.png 300w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-768x432.png 768w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-1536x864.png 1536w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-18x10.png 18w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8-600x338.png 600w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-8.png 1672w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A thermal pad is normally safer when an assembly needs compliance, electrical insulation, vibration tolerance or repeatable production placement. Pads are especially useful across multiple components because they accommodate modest height differences without turning the highest component into a rigid stop. The correct pad still needs controlled thickness, hardness and compression.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">GPUs, VRAM and mixed-height component arrays<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Memory packages around a GPU rarely form a perfect plane. Board flex, package tolerance, solder and cooler flatness all contribute. A pad can distribute contact over the array. A single rigid plate may load one high package and leave a lower one with weak contact.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The pad must also avoid lifting the cooler away from the GPU die. That means core temperature, memory temperature and mechanical imprint should be checked together. One improved sensor does not prove that the whole assembly is healthier.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Power electronics, telecom and industrial enclosures<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">MOSFETs, IGBT modules, baseband processors, RF devices, LED boards and sealed controllers often transfer heat to a metal housing. These products see vibration, thermal cycling and enclosure movement. A pad can maintain contact as the stack expands and contracts.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Serviceability matters too. A pre-cut pad can remain attached to one surface or be replaced as a controlled part. Grease around a loose metal shim may be harder to inspect and reproduce on a production line.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Electrically sensitive interfaces<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Insulating thermal pads can combine a heat path with dielectric separation. The specification should include thickness, breakdown behavior, defects, compression and the intended voltage environment. A catalog dielectric number is not permission to ignore creepage and clearance in the assembly.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Repeatable production and custom shapes<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Pads can be supplied with holes, slots, tabs, selective tack and liners. These details reduce placement errors and support manual or automated assembly. <a href=\"https:\/\/haktak.com\/vi\/thermal-pad-die-cutting-custom-shapes\/\">Thermal pad die cutting and custom shapes<\/a> can also keep material away from connectors, fasteners and keep-out zones without requiring operators to trim parts at the line.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How to Select Copper Shim or Thermal Pad Thickness Safely<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Choose thickness from the assembled gap and allowable pressure, not from the uncompressed part that came out of the device. For a pad, define a target compressed thickness across the full tolerance range. For copper, account for both thin interface layers and verify that the rigid stack cannot overload components or disturb neighboring contacts.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 1: Measure the assembled gap range<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Start with drawings if they exist, then check real assemblies. Gauge methods, pressure-sensitive film, controlled clay or putty checks, coordinate measurements and careful teardown evidence can all help. The method must not distort the gap it is trying to measure.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Record minimum, nominal and maximum values across several samples. Map the gap at more than one point if the surfaces may tilt. One measurement in the center can hide a large edge difference.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 2: Define the safe pressure window<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Identify the weakest part of the stack. That might be an exposed die, a memory package, a BGA joint, a connector, a thin PCB or a plastic housing boss. Include fastener torque, spring-clip force and tolerance accumulation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For pads, use compression-deflection data rather than hardness alone. Hardness is useful, but it does not directly state the force generated at a chosen compression.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 3: Size a thermal pad by compressed thickness<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Nominal thickness is the supplied gauge. Working thickness is what remains after assembly. The <a href=\"https:\/\/haktak.com\/vi\/how-to-select-thermal-pad-thickness-for-electronics\/\">H\u01b0\u1edbng d\u1eabn l\u1ef1a ch\u1ecdn \u0111\u1ed9 d\u00e0y mi\u1ebfng l\u00f3t nhi\u1ec7t<\/a> explains why the selected pad must cover the largest gap without becoming too highly compressed at the smallest gap.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">There is no universal compression percentage for every pad. Formulations behave differently. Use the supplier&#8217;s compression-deflection curve and establish an allowable <a href=\"https:\/\/haktak.com\/vi\/thermal-pad-compression-ratio-how-much-is-enough\/\">t\u1ef7 l\u1ec7 n\u00e9n t\u1ea3n nhi\u1ec7t<\/a> for the actual assembly.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 4: Size a copper shim as part of a complete stack<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Do not copy the nominal thickness of a removed pad. First estimate the operating gap. Then include the planned thermal grease or film on each face, shim thickness tolerance, plating and surface variation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Avoid stacking several loose shims to reach a target. They can slip, trap contamination and create additional contacts. If multiple metal layers are necessary, they need a deliberate retention and interface design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Step 5: Verify contact everywhere<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Inspect the contact pattern before trusting temperature data. Look for a complete, appropriately thin paste imprint on both shim faces or an even pad impression across the interface. Check that adjacent components still contact their intended cooling surfaces.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Measure temperatures under a realistic power profile. A no-load desktop reading is not enough for a GPU, inverter or radio that spends time at high power.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Installation and Validation: A Practical Workflow<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A useful comparison controls cleaning, placement, clamp load and test conditions. Otherwise, assembly variation can look like a material difference. Inspect contact before thermal testing, then repeat the relevant checks after cycling or vibration. The goal is not one impressive initial temperature. It is a stable interface that can be built again.<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Clean and inspect both surfaces. Remove old compound without scratching the heat spreader or cooler.<\/li>\n\n\n\n<li>Confirm shim or pad dimensions, orientation, edge clearance and liner removal.<\/li>\n\n\n\n<li>Apply the specified amount of grease to each shim face, or handle the pad without contaminating it.<\/li>\n\n\n\n<li>Assemble with a controlled torque sequence, spring load or fixture pressure.<\/li>\n\n\n\n<li>Inspect the contact pattern on an engineering sample before relying on temperature readings.<\/li>\n\n\n\n<li>Run the actual power profile and compare all relevant components, not only one sensor.<\/li>\n\n\n\n<li>Recheck thermal, mechanical and electrical behavior after the required aging profile.<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>X\u00e1c th\u1ef1c<\/strong><strong> Item<\/strong><\/td><td><strong>Useful Measurement<\/strong><\/td><td><strong>Acceptance Basis<\/strong><\/td><td><strong>Typical Failure Signal<\/strong><\/td><\/tr><tr><td>Interface contact<\/td><td>Paste imprint, pressure film or pad impression<\/td><td>Continuous contact in required area<\/td><td>Dry corners, edge loading or untouched regions<\/td><\/tr><tr><td>Mechanical load<\/td><td>Clamp force, torque, PCB strain or package limit<\/td><td>Within drawing and component limits<\/td><td>Bowing, cracked package or shifted connector<\/td><\/tr><tr><td>K\u1ebft qu\u1ea3 nhi\u1ec7t<\/td><td>Case, junction, memory and housing temperatures<\/td><td>Meets limits under real power and ambient<\/td><td>One sensor improves while another worsens<\/td><\/tr><tr><td>An to\u00e0n \u0111i\u1ec7n<\/td><td>Clearance, insulation resistance or dielectric test<\/td><td>Meets product voltage requirement<\/td><td>Intermittent short, puncture or conductive debris<\/td><\/tr><tr><td>\u0110\u1ed9 tin c\u1eady<\/td><td>Post-cycle thermal retest and teardown<\/td><td>Stable contact and acceptable drift<\/td><td>Shim movement, pump-out, compression set or cracking<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For an application-specific program, Haktak&#8217;s <a href=\"https:\/\/haktak.com\/vi\/material-selection-testing\/\">l\u1ef1a ch\u1ecdn v\u00e0 ki\u1ec3m tra v\u1eadt li\u1ec7u<\/a> support can combine thermal screening with mechanical, electrical and environmental checks.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Common Failure Modes and What They Usually Mean<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Most failures point back to contact, stack height or mechanical load. A poor temperature after reassembly does not automatically mean the selected material has low conductivity. Start by checking imprint, cooler parallelism and the complete stack. Then inspect electrical clearance and signs of movement or aging.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>V\u1ea5n \u0111\u1ec1 quan s\u00e1t \u0111\u01b0\u1ee3c<\/strong><\/td><td><strong>Likely Copper-Shim Cause<\/strong><\/td><td><strong>Likely Thermal-Pad Cause<\/strong><\/td><td><strong>What to Check First<\/strong><\/td><\/tr><tr><td>Temperature rises after reassembly<\/td><td>Poor paste coverage or wrong shim thickness<\/td><td>Wrong thickness, low compression or liner left on<\/td><td>Contact imprint and full stack height<\/td><\/tr><tr><td>GPU core becomes hotter after VRAM work<\/td><td>Shim lifts cooler away from the die<\/td><td>Pads are too thick or too hard<\/td><td>Core contact and cooler parallelism<\/td><\/tr><tr><td>One component is hotter than its neighbors<\/td><td>Height variation or tilted shim<\/td><td>Uneven compression or cut-part placement<\/td><td>Gap map and pressure distribution<\/td><\/tr><tr><td>L\u1ed7i \u0111i\u1ec7n ch\u1eadp ch\u1eddn<\/td><td>Copper edge touches circuitry or debris moves<\/td><td>Insulating layer is damaged or punctured<\/td><td>Clearance and dielectric condition<\/td><\/tr><tr><td>Performance degrades after cycling<\/td><td>Paste pump-out, shim movement or oxidation<\/td><td>Compression set, cracking or bleed<\/td><td>Post-aging teardown and thermal retest<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The broader guide to <a href=\"https:\/\/haktak.com\/vi\/why-thermal-pads-fail\/\">why thermal pads fail<\/a> covers thickness error, poor storage, contamination and long-term mechanical change. If the proposed fix is simply adding layers, read <a href=\"https:\/\/haktak.com\/vi\/can-you-stack-thermal-pads\/\">whether thermal pads can be stacked<\/a> first. Additional interfaces make alignment and compression harder to predict.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Standards and Data That Make Comparisons More Trustworthy<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Useful comparisons state thickness, pressure, contact area, test method and aging condition. Thermal conductivity alone is not enough. Ask a pad supplier for impedance and compression data, and ask a shim supplier for alloy, tolerance, flatness and edge quality. Then validate the finished joint because material data does not reproduce every real enclosure or cooler.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">ASTM D5470 is widely used to characterize thermal transmission properties of interface materials. It is useful because it recognizes that pressure and contact matter. It does not guarantee the same performance in a GPU cooler, power module or outdoor controller with different surfaces and loads.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a thermal pad, request:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u0110\u1ed9 d\u00e0y v\u00e0 dung sai<\/li>\n\n\n\n<li>Thermal conductivity test method<\/li>\n\n\n\n<li>Thermal impedance at stated pressure and thickness<\/li>\n\n\n\n<li>Hardness method and value<\/li>\n\n\n\n<li>Compression-deflection curve<\/li>\n\n\n\n<li>Dielectric strength or breakdown data where needed<\/li>\n\n\n\n<li>Compression set, thermal aging and environmental conditions<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For a copper shim, request:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Copper alloy and conductivity basis<\/li>\n\n\n\n<li>\u0110\u1ed9 d\u00e0y v\u00e0 dung sai<\/li>\n\n\n\n<li>Flatness and surface roughness<\/li>\n\n\n\n<li>Burr and edge-control specification<\/li>\n\n\n\n<li>Plating type and thickness, if used<\/li>\n\n\n\n<li>Cleanliness, packaging and oxidation controls<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The Copper Development Association&#8217;s official <a href=\"https:\/\/alloys.copper.org\/alloy\/C11000\" target=\"_blank\" rel=\"noopener\">C11000 copper alloy data<\/a> provides useful context for the metal&#8217;s conductivity and physical behavior. Those properties explain why copper is attractive, but the final thermal joint still has to be tested as an assembly.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Copper Shim vs Thermal Pad Selection Checklist<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Choose a thermal pad when the gap varies, the parts are fragile or electrical isolation is required. Evaluate a copper shim stack when dimensions are precise, surfaces are flat, load is controlled and thin interface layers can be applied consistently. If neither option fits the geometry, reconsider the interface instead of forcing a material into the wrong job.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Work through these questions in order:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li>Is electrical insulation required at the interface?<\/li>\n\n\n\n<li>Does the gap vary between locations, units or operating temperatures?<\/li>\n\n\n\n<li>Can the assembly tolerate rigid load transfer?<\/li>\n\n\n\n<li>Are both surfaces flat and parallel enough for a shim?<\/li>\n\n\n\n<li>Can thin interface layers be applied with repeatable coverage?<\/li>\n\n\n\n<li>Is the shim positively retained against movement?<\/li>\n\n\n\n<li>Does the design survive thermal cycling, shock and vibration?<\/li>\n\n\n\n<li>Can placement and contact be inspected in production?<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Three practical outcomes follow:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Choose a thermal pad<\/strong> for variable gaps, low-pressure interfaces, mixed-height arrays and electrical isolation. If pressure is a concern, compare <a href=\"https:\/\/haktak.com\/vi\/soft-vs-hard-thermal-pads-which-is-better\/\">soft and hard thermal pads<\/a> using compression-deflection behavior, not feel alone.<\/li>\n\n\n\n<li><strong>Evaluate a copper shim stack<\/strong> for precise, stable interfaces where load and retention are engineered.<\/li>\n\n\n\n<li><strong>Consider another gap-filling approach<\/strong> when the gap is large, irregular or changes across components. The comparison of <a href=\"https:\/\/haktak.com\/vi\/thermal-putty-vs-thermal-pad-uneven-gaps\/\">thermal putty and thermal pads for uneven gaps<\/a> explains one alternative.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">What to Send Haktak for a Material Recommendation<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-1024x576.png\" alt=\"What to Send Haktak for a Material Recommendation\" class=\"wp-image-1877\" srcset=\"https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-1024x576.png 1024w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-300x169.png 300w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-768x432.png 768w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-1536x864.png 1536w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-18x10.png 18w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9-600x338.png 600w, https:\/\/haktak.com\/wp-content\/uploads\/2026\/08\/image-9.png 1672w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A useful recommendation starts with the mechanical drawing and operating conditions, not just a target conductivity. Share the gap range, heat load, cooling surface, pressure limit, voltage requirement and reliability profile. With those inputs, Haktak can screen the wider TIM family and recommend a pad, putty, grease or custom format for validation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Please include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Drawing, interface area and keep-out zones<\/li>\n\n\n\n<li>Minimum, nominal and maximum assembled gap<\/li>\n\n\n\n<li>Heat source, power and temperature target<\/li>\n\n\n\n<li>Heat sink, cold plate or housing material and flatness<\/li>\n\n\n\n<li>Screw, clip or fixture method and pressure limit<\/li>\n\n\n\n<li>Voltage, dielectric and grounding requirements<\/li>\n\n\n\n<li>Operating temperature, humidity, vibration and service-life target<\/li>\n\n\n\n<li>Prototype quantity, production volume and preferred packaging<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Review the broader range of <a href=\"https:\/\/haktak.com\/vi\/thermal-interface-materials\/\">v\u1eadt li\u1ec7u d\u1eabn nhi\u1ec7t giao di\u1ec7n<\/a> ho\u1eb7c <strong>request a thermal interface recommendation<\/strong> with your drawing and operating conditions.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">These questions cover the practical issues buyers, engineers and repair technicians raise most often. The short version is simple: copper is rigid and conductive; pads are compliant and can be insulating. Thickness, contact pressure and the full assembly determine whether either option works safely.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. Is a copper shim better than a thermal pad?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Only in the right mechanical design. Copper has much higher bulk conductivity, but a shim needs controlled thickness, flat surfaces, suitable pressure and thin interface material on both faces. A thermal pad is usually more forgiving where gaps vary, components are fragile or electrical isolation is required. Compare total interface resistance and reliability, not conductivity alone.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">2. Does a copper shim need thermal paste on both sides?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Usually, yes. The paste fills microscopic surface roughness between the heat source and shim, then between the shim and cooler. Use a thin, controlled layer. Paste should remove air, not become a thick gap filler. The exact interface material and application amount should be validated for the temperature, pressure and service life.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. How do I choose the correct copper shim thickness?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Measure the assembled gap, including its minimum and maximum tolerance. Subtract the intended thin interface layers and check that the resulting stack does not create excessive force. Do not simply copy the nominal thickness printed on a removed thermal pad because that pad probably operated in a compressed state.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">4. Can I replace GPU or VRAM thermal pads with copper shims?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">It is possible in a carefully measured design, but it carries real risk. A wrong shim can lift the cooler from the GPU die, bend the PCB, load memory packages or cause an electrical short. VRAM heights can also vary. Check the full cooler contact pattern and all component temperatures before calling the modification successful.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">5. Can a copper shim crack a GPU die or bend a PCB?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Yes. Copper transfers load directly because it does not compress like a pad. An oversized shim or uneven cooler can create a hard point over a package. Exposed dies are especially sensitive. Define the gap and pressure window first, then inspect board strain, cooler parallelism and contact during validation.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">6. Are copper shims electrically conductive?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Yes. A copper shim can short exposed contacts, nearby passives or PCB features if it is misplaced or moves. Maintain edge clearance and use positive retention. If insulation is added, include that film or coating in thermal and dielectric testing because it changes both resistance and stack thickness.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">7. Can I put a thermal pad on both sides of a copper shim?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Only as part of a designed large-gap stack. Thin compliant layers can help a metal spreader contact imperfect surfaces, but two thick pads plus a loose shim create extra interfaces and uncertain compression. A single suitable pad, thermal putty or redesigned heat spreader may be more repeatable.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">8. Can thermal pads be stacked instead of using a thicker pad?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Stacking is generally less predictable than using one correctly sized pad. The layer boundary adds contact resistance, and the pads can shift or compress unevenly. For a prototype emergency it may reveal whether more gap filling is needed, but production should use a validated single thickness or another designed interface.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">9. Which lasts longer, a copper shim or a thermal pad?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The copper body itself can remain stable for a long time, but the complete shim assembly still includes paste, plating, retention and nearby materials that can age. A pad&#8217;s life depends on formulation, compression set, temperature and cycling. Neither option has a universal life advantage without a defined environment and test profile.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">10. How should I test a copper shim or thermal pad before production?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Check contact and pressure first, then measure all relevant component temperatures under realistic power and ambient conditions. Add electrical testing where insulation matters. Repeat thermal measurements after cycling, vibration or aging, then perform a teardown. Look for movement, pump-out, cracking, bleed, permanent compression and changes in contact imprint.<\/p>\n<\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>A copper shim is not automatically better than a thermal pad, even though copper has much higher bulk thermal conductivity. [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":1872,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1871","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-haktak-blog"],"_links":{"self":[{"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/posts\/1871","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/comments?post=1871"}],"version-history":[{"count":2,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/posts\/1871\/revisions"}],"predecessor-version":[{"id":1887,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/posts\/1871\/revisions\/1887"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/media\/1872"}],"wp:attachment":[{"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/media?parent=1871"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/categories?post=1871"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/haktak.com\/vi\/wp-json\/wp\/v2\/tags?post=1871"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}