{"id":17164,"date":"2025-12-16T11:10:18","date_gmt":"2025-12-16T03:10:18","guid":{"rendered":"https:\/\/www.bestpcbs.com\/blog\/?p=17164"},"modified":"2025-12-16T11:55:09","modified_gmt":"2025-12-16T03:55:09","slug":"why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates","status":"publish","type":"post","link":"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/","title":{"rendered":"Why Does Yellow Discoloration Appear on Al\u2082O\u2083 DBC Substrates?"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#What_Is_an_Al%E2%82%82O%E2%82%83_DBC_Substrate\" >What Is an Al\u2082O\u2083 DBC Substrate?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#How_Does_the_DBC_Bonding_Process_Work\" >How Does the DBC Bonding Process Work?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#What_Is_the_Bonding_Layer_Made_Of\" >What Is the Bonding Layer Made Of?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#Why_Does_Yellow_Discoloration_Appear_on_the_Ceramic_Surface\" >Why Does Yellow Discoloration Appear on the Ceramic Surface?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#How_Does_the_DBC_Bonding_Process_Create_a_Strong_Interface\" >How Does the DBC Bonding Process Create a Strong Interface?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#Why_Is_the_Yellow_Color_Often_Non-Uniform\" >Why Is the Yellow Color Often Non-Uniform?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#Does_Yellow_Discoloration_Affect_DBC_Substrate_Performance\" >Does Yellow Discoloration Affect DBC Substrate Performance?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#What_Is_an_Al%E2%82%82O%E2%82%83_DBC_Substrate_Used_For\" >What Is an Al\u2082O\u2083 DBC Substrate Used For?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#How_EBest_Circuit_Best_Technology_Controls_DBC_Substrate_Quality\" >How EBest Circuit (Best Technology) Controls DBC Substrate Quality?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/#Conclusion\" >Conclusion<\/a><\/li><\/ul><\/nav><\/div>\n<div class=\"yzp-no-index\"><\/div>\n<p>Yellow discoloration on Al\u2082O\u2083 DBC substrates layers is occasionally observed after <a href=\"https:\/\/www.bestpcbs.com\/products\/DCB-ceramic-pcb.htm\" title=\"\">DBC bonding<\/a>. For many engineers, this visual change raises a practical question: <em>does ceramic yellowing indicate a performance risk? Why does it become yellow? <\/em>This article explains the <strong>material mechanisms behind discoloration<\/strong>, and why it <strong>does not compromise DBC substrate reliability<\/strong>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_Is_an_Al%E2%82%82O%E2%82%83_DBC_Substrate\"><\/span>What Is an Al\u2082O\u2083 DBC Substrate?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>An Al\u2082O\u2083 DBC (<a href=\"https:\/\/www.bstceramicpcb.com\/news\/industry-knowledge\/introduction-to-dbc-direct-bonded-copper-substrate.html\" title=\"\">Direct Bonded Copper<\/a>) substrate is a ceramic metal composite formed by directly bonding copper foil to an alumina ceramic plate under high temperature and controlled oxygen atmosphere.<\/p>\n\n\n\n<p>This structure is widely used in power modules, inverters, IGBT packages, and automotive electronics, where thermal conductivity and electrical insulation are critical. The bonding process relies on interfacial chemical reactions, not adhesives.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/afb68d83de4140cca0305bb502aaeb5e.png\"><img decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/afb68d83de4140cca0305bb502aaeb5e.png\" alt=\"What Is an Al\u2082O\u2083 DBC Substrate? https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al\u2082o\u2083-dbc-substrates\/\" class=\"wp-image-17285\"\/><\/a><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"How_Does_the_DBC_Bonding_Process_Work\"><\/span>How Does the DBC Bonding Process Work?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>During DBC sintering, copper and alumina interact through a thermally activated oxidation-reduction mechanism.<\/p>\n\n\n\n<p>At elevated temperatures and controlled oxygen levels:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Copper surface oxidizes to form a thin Cu\u2082O layer<\/li>\n\n\n\n<li>When the temperature exceeds the eutectic point, a Cu\u2013Cu\u2082O eutectic liquid phase forms<\/li>\n\n\n\n<li>This liquid phase wets both copper and Al\u2082O\u2083 surfaces effectively<\/li>\n\n\n\n<li>Copper oxide reacts with alumina to form CuAlO\u2082<\/li>\n<\/ul>\n\n\n\n<p>The reaction can be summarized as:<\/p>\n\n\n\n<p><strong>Cu<\/strong><strong>\u2082O + Al<\/strong><strong>\u2082O<\/strong><strong>\u2083 <\/strong><strong>\u2192 CuAlO<\/strong><strong>\u2082<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/Cu2OAl2O3\u2192CuAlO2.png\"><img decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/Cu2OAl2O3\u2192CuAlO2.png\" alt=\"How Does the DBC Bonding Process Work?https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al\u2082o\u2083-dbc-substrates\/\" class=\"wp-image-17286\"\/><\/a><\/figure>\n\n\n\n<p>CuAlO\u2082 acts as a <strong>ceramic-like bonding phase<\/strong>, enabling strong metallurgical adhesion between copper and ceramic.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_Is_the_Bonding_Layer_Made_Of\"><\/span>What Is the Bonding Layer Made Of?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>After bonding, a thin interfacial layer composed mainly of <strong>CuAlO<\/strong><strong>\u2082<\/strong> exists between copper and Al\u2082O\u2083.<\/p>\n\n\n\n<p>Key characteristics of this layer:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ceramic oxide with dark red to yellowish color<\/li>\n\n\n\n<li>Excellent resistance to acids and alkalis<\/li>\n\n\n\n<li>Difficult to remove completely using standard copper etching chemicals<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><a href=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/What-Is-the-Bonding-Layer-Made.png\"><img decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/What-Is-the-Bonding-Layer-Made.png\" alt=\"What Is the Bonding Layer Made Of?https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al\u2082o\u2083-dbc-substrates\/\" class=\"wp-image-17287\" style=\"width:505px;height:auto\"\/><\/a><\/figure>\n\n\n\n<p>When surface copper is etched away, the bonded ceramic area often appears <strong>more yellow<\/strong> than unbonded areas. This visual difference directly relates to the presence of the bonding layer.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Why_Does_Yellow_Discoloration_Appear_on_the_Ceramic_Surface\"><\/span>Why Does Yellow Discoloration Appear on the Ceramic Surface?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Yellowing originates from two simultaneous material phenomena, both occurring during high-temperature DBC sintering.<\/p>\n\n\n\n<p><strong>1. Influence of the CuAlO<\/strong><strong>\u2082 Bonding Layer<\/strong><\/p>\n\n\n\n<p>CuAlO\u2082 itself has a reddish-yellow ceramic appearance. Because this compound forms through interfacial reactions, its thickness is not perfectly uniform across the substrate.<\/p>\n\n\n\n<p>Even nanometer-level thickness variation can lead to visible color differences after copper removal.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/ec13e8adccff4f409f50d6f20c7a2c55.png\"><img decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/ec13e8adccff4f409f50d6f20c7a2c55.png\" alt=\"Why Does Yellow Discoloration Appear on the Ceramic Surface?https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al\u2082o\u2083-dbc-substrates\/\" class=\"wp-image-17289\"\/><\/a><\/figure>\n\n\n\n<p><strong>2. Migration of Ceramic Sintering Additives<\/strong><\/p>\n\n\n\n<p>Most industrial Al\u2082O\u2083 ceramics used for DBC are 96% alumina, not 100% pure.<\/p>\n\n\n\n<p>They contain small amounts of sintering additives such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>SiO\u2082<\/li>\n\n\n\n<li>CaO<\/li>\n\n\n\n<li>MgO<\/li>\n<\/ul>\n\n\n\n<p>These additives improve ceramic densification during firing.<\/p>\n\n\n\n<p>During DBC bonding:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>High temperatures cause partial diffusion of these additives toward the surface<\/li>\n\n\n\n<li>EDX analysis shows increased Si, Ca, and Mg content in yellowed areas<\/li>\n\n\n\n<li>Higher surface concentration of these oxides correlates with yellow coloration<\/li>\n<\/ul>\n\n\n\n<p>This behavior is consistent with ceramic sintering literature, which confirms that increased SiO\u2082 content can cause alumina yellowing.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"How_Does_the_DBC_Bonding_Process_Create_a_Strong_Interface\"><\/span>How Does the DBC Bonding Process Create a Strong Interface?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>DBC bonding relies on controlled oxidation and eutectic reactions at high temperature.<\/p>\n\n\n\n<p>During sintering:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Copper forms a thin Cu\u2082O layer under controlled oxygen content<\/li>\n\n\n\n<li>Above the eutectic temperature, a Cu\u2013Cu\u2082O liquid phase appears<\/li>\n\n\n\n<li>This liquid wets both copper and Al\u2082O\u2083 surfaces<\/li>\n\n\n\n<li>Interfacial reactions form CuAlO\u2082, enabling direct bonding<\/li>\n<\/ul>\n\n\n\n<p>This mechanism creates a chemically bonded interface, which is critical for long-term thermal cycling stability.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Why_Is_the_Yellow_Color_Often_Non-Uniform\"><\/span>Why Is the Yellow Color Often Non-Uniform?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>The discoloration is rarely perfectly even. This non-uniformity comes from <strong>reaction uncertainty<\/strong>, not process instability.<\/p>\n\n\n\n<p>Key reasons include:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>CuAlO\u2082 formation varies slightly across the bonding interface<\/li>\n\n\n\n<li>Sintering additive diffusion is not perfectly uniform at the micro-scale<\/li>\n\n\n\n<li>Both effects occur at nanometer-level thickness differences<\/li>\n<\/ul>\n\n\n\n<p>Even minor variations become visible on ceramic surfaces due to light reflection and oxide color sensitivity.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Does_Yellow_Discoloration_Affect_DBC_Substrate_Performance\"><\/span>Does Yellow Discoloration Affect DBC Substrate Performance?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>This is the most important question for engineers and customers. Extensive testing was performed on:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>DBC substrates with <strong>severe yellow discoloration<\/strong><\/li>\n\n\n\n<li>DBC substrates with <strong>minimal or no discoloration<\/strong><\/li>\n<\/ul>\n\n\n\n<p>The results show:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>No meaningful difference in electrical insulation<\/li>\n\n\n\n<li>No degradation in thermal performance<\/li>\n\n\n\n<li>No impact on mechanical bonding strength<\/li>\n\n\n\n<li>No reliability concerns in functional testing<\/li>\n<\/ul>\n\n\n\n<p>In short, <strong>yellow discoloration is a cosmetic phenomenon<\/strong>, not a functional defect.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/Element-Analysis-on-Yellow-Discoloration-Area-1.png\"><img decoding=\"async\" src=\"https:\/\/www.bestpcbs.com\/blog\/wp-content\/uploads\/2025\/12\/Element-Analysis-on-Yellow-Discoloration-Area-1.png\" alt=\"Does Yellow Discoloration Affect DBC Substrate Performance? https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al\u2082o\u2083-dbc-substrates\/\" class=\"wp-image-17292\"\/><\/a><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_Is_an_Al%E2%82%82O%E2%82%83_DBC_Substrate_Used_For\"><\/span>What Is an Al\u2082O\u2083 DBC Substrate Used For?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p><a href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/\" title=\"\">Al\u2082O\u2083 DBC substrates<\/a> are widely applied in:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>IGBT and power module packaging<\/li>\n\n\n\n<li>Automotive inverters and motor drives<\/li>\n\n\n\n<li>Industrial power supplies<\/li>\n\n\n\n<li>Renewable energy systems<\/li>\n<\/ul>\n\n\n\n<p>Their value lies in a balanced combination of electrical insulation, thermal conduction, and mechanical stability. The copper\u2013ceramic interface is formed through a metallurgical bonding process rather than adhesives or plating.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"How_EBest_Circuit_Best_Technology_Controls_DBC_Substrate_Quality\"><\/span>How EBest Circuit (Best Technology) Controls DBC Substrate Quality?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>At <a href=\"https:\/\/www.bestpcbs.com\/\" title=\"\">EBest Circuit (Best Technology)<\/a>, DBC substrates are produced with strict control over:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Oxygen concentration during bonding<\/li>\n\n\n\n<li>Temperature uniformity across furnaces<\/li>\n\n\n\n<li>Ceramic material composition and sourcing<\/li>\n\n\n\n<li>Post-bonding inspection and testing<\/li>\n<\/ul>\n\n\n\n<p>Our engineering team evaluates DBC substrates based on <strong>measurable electrical and thermal performance<\/strong>, not cosmetic appearance alone.<\/p>\n\n\n\n<p>This approach ensures stable results for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Automotive-grade power electronics<\/li>\n\n\n\n<li>Industrial and renewable energy systems<\/li>\n\n\n\n<li>High-reliability inverter applications<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Conclusion\"><\/span>Conclusion<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>Yellow discoloration on <a href=\"https:\/\/www.bestpcbs.com\/blog\/2025\/12\/why-does-yellow-discoloration-appear-on-al%e2%82%82o%e2%82%83-dbc-substrates\/\" title=\"\">Al\u2082O\u2083 DBC substrates<\/a> originates from:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>CuAlO\u2082 formation at the bonding interface<\/li>\n\n\n\n<li>Surface diffusion of ceramic sintering additives<\/li>\n<\/ul>\n\n\n\n<p>Both effects occur during normal DBC sintering and may vary slightly across the substrate.<br>Extensive testing confirms that <strong>this discoloration does not affect DBC performance or reliability<\/strong>.<\/p>\n\n\n\n<p>For power electronics applications, <strong>engineering performance matters far more than visual color uniformity<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Yellow discoloration on Al\u2082O\u2083 DBC substrates layers is occasionally observed after DBC bonding. For many engineers, this visual change raises a practical question: does ceramic yellowing indicate a performance risk? Why does it become yellow? This article explains the material mechanisms behind discoloration, and why it does not compromise DBC substrate reliability. What Is an [&hellip;]<\/p>\n","protected":false},"author":623,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"footnotes":""},"categories":[175,174,21,169,37],"tags":[3055,3056],"class_list":["post-17164","post","type-post","status-publish","format-standard","hentry","category-best-pcb","category-bestpcb","category-ceramic-pcb","category-dbc-substrate","category-faq","tag-al2o3-dbc-substrate","tag-dbc-substrate"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts\/17164","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/users\/623"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/comments?post=17164"}],"version-history":[{"count":3,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts\/17164\/revisions"}],"predecessor-version":[{"id":17301,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/posts\/17164\/revisions\/17301"}],"wp:attachment":[{"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/media?parent=17164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/categories?post=17164"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bestpcbs.com\/blog\/wp-json\/wp\/v2\/tags?post=17164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}