L'alumina \u00e9s el substrat cer\u00e0mic per defecte per una ra\u00f3. \u00c9s barat, resistent i f\u00e0cil de metallitzar. Tamb\u00e9 \u00e9s un mal tub de calor. Una placa d'Al\u2082O\u2083 96% t\u00e9 una conductivitat d'uns 20\u201330 W\/m\u00b7K. El nitrur d'alumini, si es fa correctament, se situa en el rang de 170\u2013200 W\/m\u00b7K, de vegades una mica per sobre de 200. La teoria per a un cristall \u00fanic perfecte \u00e9s de gaireb\u00e9 320. Ning\u00fa no el comercialitza. El que comercialitzem \u00e9s un a\u00efllant sinteritzat que pot dissipar la calor del xip d'un m\u00f2dul de pot\u00e8ncia sense convertir-se en conductor.<\/p>\n
Aquesta combinaci\u00f3 \u00e9s la soluci\u00f3. Els metalls conducten la calor i l'electricitat. La majoria de cer\u00e0miques bloquegen el corrent i ret\u00e9nen la calor. El nitrur d'alumini fa de conductor t\u00e8rmic i d'a\u00efllant alhora, amb un CTE d'uns 4,5 ppm\/\u00b0C \u2014 proper al del silici. L'alumina s'expandeix m\u00e9s, al voltant de 6,5\u20137,5 ppm\/\u00b0C. En un dispositiu IGBT d'alta pot\u00e8ncia o de SiC, aquesta incompatibilitat es manifesta com a fatiga de la soldadura i pel descascament de la l\u00e0mina de coure. El BeO condueix encara millor i, tot i aix\u00ed, l'evitem sempre que podem. La toxicitat no \u00e9s una nota a peu de p\u00e0gina de la fitxa t\u00e8cnica.<\/p>\n
L'oxigen \u00e9s la impuresa que espatlla la hist\u00f2ria de la conductivitat. L'oxigen de la xarxa crea buits d'alumini. Els fonons s'escampen. Un pols amb un parell de per cent d'oxigen es sintera en alguna cosa que s'assembla a l'AlN i mesura m\u00e9s a prop de 100 W\/m\u00b7K. El pols amb baix contingut d'oxigen, combinat amb un agent d'esmaltat que atrau l'oxigen cap a una fase de l\u00edmit de gra \u2014l'yttria \u00e9s la m\u00e9s habitual\u2014 \u00e9s com s'obt\u00e9 la qualitat de m\u00e9s de 170. La densitat ha de ser alta. Un porus residual \u00e9s un altre lloc de dispersi\u00f3. Per tant, \u201csubstrat d'AlN\u201d en un PO no \u00e9s una qualitat. Demaneu la conductivitat t\u00e8rmica, no nom\u00e9s la qu\u00edmica.<\/p>\n
La manipulaci\u00f3 de pols \u00e9s on els tallers es sorprenen. Les fin\u00edssimes hidr\u00f2lisis d'AlN. Si la deixes en aire humit, hi creix una pell d'hidroxid i augmenta l'oxigen que acabes de pagar per eliminar. Emmagatzematge sec, temps d'obertura curt, de vegades un tractament superficial. Aix\u00f2 no \u00e9s cap mania. \u00c9s com el valor k sobreviu fins al forn.<\/p>\n
Utilitzem nitrur d'alumini all\u00e0 on la pila t\u00e8rmica realment ho necessita: plaques de pot\u00e8ncia DBC i DPC, paquets RF, submontatges de l\u00e0ser i LED, algunes peces de processos de semiconductors. Si el xip \u00e9s de pocs watts i el dissipador \u00e9s el coll d'ampolla, l'alumina encara guanya en preu. Si est\u00e0s dissipant desenes de watts a trav\u00e9s d'una cer\u00e0mica fina cap al coure, la caiguda de tensi\u00f3 al substrat d'alumina ja no \u00e9s gratu\u00efta. La cer\u00e0mica costa m\u00e9s. El m\u00f2dul que no es limita ni es delamina \u00e9s el retorn.<\/p>\n
El mecanitzat i la metalitzaci\u00f3 requereixen la mateixa honestedat. L'AlN no \u00e9s tan informal com l'alumina 96%. Les vores es trenquen. L'encolatge de coure ha de coincidir amb l'expansi\u00f3. Un bell disc de 180 W\/m\u00b7K amb una mala interf\u00edcie \u00e9s nom\u00e9s un a\u00efllant car. Especifiqueu k, gruix, superf\u00edcie i el sistema met\u00e0l\u00b7lic conjuntament. El nitrur d'alumini \u00e9s una via de calor que resulta ser una cer\u00e0mica. Tracteu-lo aix\u00ed i es mereix el sobrepreu. Tracteu-lo com a alumina blanca amb un millor fullet\u00f3 i no se'l mereixer\u00e0.<\/p>","protected":false},"excerpt":{"rendered":"
Aluminium Nitride Moves Heat Like a Metal and Still Blocks Current Alumina is the default ceramic substrate for a reason. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","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":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-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":"","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-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":"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":""},"mobile":{"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":""}},"footnotes":""},"categories":[2],"tags":[],"class_list":["post-74","post","type-post","status-publish","format-standard","hentry","category-products-related"],"_links":{"self":[{"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/posts\/74","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/comments?post=74"}],"version-history":[{"count":1,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/posts\/74\/revisions"}],"predecessor-version":[{"id":77,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/posts\/74\/revisions\/77"}],"wp:attachment":[{"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/media?parent=74"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/categories?post=74"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/aluminiumnitride.com\/ca\/wp-json\/wp\/v2\/tags?post=74"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}