Maziko a graphite okhala ndi SiC nthawi zambiri amagwiritsidwa ntchito pothandizira ndikutenthetsa ma crystal substrates amodzi mu zida za metal-organic chemical vapor deposition (MOCVD). Kukhazikika kwa kutentha, kufanana kwa kutentha ndi magawo ena ogwirira ntchito a maziko a graphite okhala ndi SiC amachita gawo lofunika kwambiri pakukula kwa zinthu za epitaxial, kotero ndiye gawo lofunikira kwambiri la zida za MOCVD.
Pakupanga ma wafer, zigawo za epitaxial zimapangidwanso pa ma wafer substrates ena kuti zikhale zosavuta kupanga zipangizo. Zipangizo zodziwika bwino zotulutsa kuwala kwa LED zimafunika kukonzekera zigawo za epitaxial za GaAs pa ma silicon substrates; SiC epitaxial layer imakulitsidwa pa gawo loyendetsa SiC kuti ipange zipangizo monga SBD, MOSFET, ndi zina zotero, kuti ipange magetsi ambiri, magetsi amphamvu komanso mphamvu zina; GaN epitaxial layer imapangidwa pa gawo losungira madzi la SiC kuti ipangenso HEMT ndi zipangizo zina za RF monga kulumikizana. Njirayi ndi yosiyana ndi zida za CVD.
Mu zida za CVD, gawo lapansi silingaikidwe mwachindunji pachitsulo kapena kungoyikidwa pa maziko kuti liyike epitaxial, chifukwa limakhudza kuyenda kwa mpweya (wopingasa, wowongoka), kutentha, kupanikizika, kukhazikika, kutaya zonyansa ndi zina zomwe zimayambitsa. Chifukwa chake, pamafunika maziko, kenako gawo lapansi limayikidwa pa diski, kenako epitaxial imayikidwa pa gawo lapansi pogwiritsa ntchito ukadaulo wa CVD, ndipo maziko awa ndi maziko a graphite okhala ndi SiC (omwe amadziwikanso kuti thireyi).
Maziko a graphite okhala ndi SiC nthawi zambiri amagwiritsidwa ntchito pothandizira ndikutenthetsa ma crystal substrates amodzi mu zida za metal-organic chemical vapor deposition (MOCVD). Kukhazikika kwa kutentha, kufanana kwa kutentha ndi magawo ena ogwirira ntchito a maziko a graphite okhala ndi SiC amachita gawo lofunika kwambiri pakukula kwa zinthu za epitaxial, kotero ndiye gawo lofunikira kwambiri la zida za MOCVD.
Kuyika nthunzi ya metal-organic chemical vapor (MOCVD) ndi ukadaulo waukulu wa kukula kwa mafilimu a GaN mu LED yabuluu. Ili ndi ubwino wosavuta kugwiritsa ntchito, kukula kowongolera komanso kuyera kwambiri kwa mafilimu a GaN. Monga gawo lofunikira mu chipinda chochitira zinthu cha zida za MOCVD, maziko ogwiritsira ntchito kukula kwa filimu ya GaN ayenera kukhala ndi ubwino wokana kutentha kwambiri, kuyendetsa kutentha kofanana, kukhazikika kwa mankhwala, kukana kutentha kwambiri, ndi zina zotero. Zinthu za Graphite zimatha kukwaniritsa zomwe zili pamwambapa.
Monga chimodzi mwa zigawo zazikulu za zida za MOCVD, maziko a graphite ndiye chonyamulira ndi kutentha kwa substrate, zomwe zimatsimikizira mwachindunji kufanana ndi kuyera kwa zinthu za filimuyo, kotero ubwino wake umakhudza mwachindunji kukonzekera kwa pepala la epitaxial, ndipo nthawi yomweyo, ndi kuwonjezeka kwa kuchuluka kwa ntchito ndi kusintha kwa magwiridwe antchito, ndizosavuta kuvala, zomwe ndi za zinthu zogwiritsidwa ntchito.
Ngakhale kuti graphite ili ndi kutentha kwabwino komanso kukhazikika, ili ndi ubwino wabwino ngati gawo loyambira la zida za MOCVD, koma popanga, graphite idzawononga ufa chifukwa cha mpweya wotsalira ndi zinthu zachilengedwe zachitsulo, ndipo nthawi yogwira ntchito ya maziko a graphite idzachepa kwambiri. Nthawi yomweyo, ufa wa graphite womwe ukugwa udzayambitsa kuipitsidwa kwa chip.
Kutulukira kwa ukadaulo wopaka utoto kungapereke kukhazikika kwa ufa pamwamba, kukulitsa kutentha, ndikulinganiza kugawa kwa kutentha, komwe kwakhala ukadaulo waukulu wothetsera vutoli. Maziko a graphite m'malo ogwiritsira ntchito zida za MOCVD, utoto wa graphite pansi uyenera kukwaniritsa izi:
(1) Maziko a graphite akhoza kukulungidwa bwino, ndipo kuchuluka kwake ndi kwabwino, apo ayi maziko a graphite ndi osavuta kuwononga mu mpweya wowononga.
(2) Mphamvu yophatikizana ndi maziko a graphite ndi yayikulu kuti zitsimikizire kuti chophimbacho sichikugwa mosavuta pambuyo pa kutentha kwakukulu komanso kutentha kochepa.
(3) Ili ndi kukhazikika kwabwino kwa mankhwala kuti ipewe kulephera kwa utoto mumlengalenga wotentha kwambiri komanso wowononga.
SiC ili ndi ubwino wokana dzimbiri, kutentha kwambiri, kukana kutentha kwambiri komanso kukhazikika kwa mankhwala, ndipo imatha kugwira ntchito bwino mumlengalenga wa GaN epitaxial. Kuphatikiza apo, kuchuluka kwa kutentha kwa SiC kumasiyana pang'ono ndi kwa graphite, kotero SiC ndiye chinthu chomwe chimakondedwa kwambiri pakuphimba pamwamba pa maziko a graphite.
Pakadali pano, SiC yodziwika bwino makamaka ndi ya 3C, 4H ndi 6H, ndipo kugwiritsa ntchito kwa SiC kwa mitundu yosiyanasiyana ya makristalo ndikosiyana. Mwachitsanzo, 4H-SiC imatha kupanga zida zamagetsi amphamvu kwambiri; 6H-SiC ndiyo yokhazikika kwambiri ndipo imatha kupanga zida zamagetsi; Chifukwa cha kapangidwe kake kofanana ndi GaN, 3C-SiC ingagwiritsidwe ntchito kupanga GaN epitaxial layer ndikupanga zida za SiC-GaN RF. 3C-SiC imadziwikanso kuti β-SiC, ndipo kugwiritsa ntchito β-SiC kofunikira ndi filimu ndi zinthu zokutira, kotero β-SiC pakadali pano ndiye chinthu chachikulu chopangira zokutira.
Njira yokonzekera chophimba cha silicon carbide
Pakadali pano, njira zokonzekera zokutira za SiC zikuphatikizapo njira ya gel-sol, njira yolumikizira, njira yophimba burashi, njira yopopera plasma, njira yochitira mpweya wa mankhwala (CVR) ndi njira yoikamo mpweya wa mankhwala (CVD).
Njira yoyika:
Njirayi ndi mtundu wa sintering yolimba kwambiri pa kutentha, yomwe imagwiritsa ntchito makamaka chisakanizo cha ufa wa Si ndi ufa wa C ngati ufa wothira, graphite matrix imayikidwa mu ufa wothira, ndipo sintering yotentha kwambiri imachitidwa mu mpweya wopanda mpweya, ndipo potsiriza SiC imakutidwa pamwamba pa graphite matrix. Njirayi ndi yosavuta ndipo kuphatikiza pakati pa graphite ndi substrate ndikwabwino, koma kufanana kwa kuvala motsatira njira yokhuthala ndi koipa, zomwe zimakhala zosavuta kupanga mabowo ambiri ndikupangitsa kuti pakhale kukana koipa kwa okosijeni.
Njira yophikira burashi:
Njira yophikira burashi makamaka ndi kutsuka zinthu zopangira zamadzimadzi pamwamba pa graphite matrix, kenako kutsuka zinthuzo pa kutentha kwina kuti akonze chophimbacho. Njirayi ndi yosavuta ndipo mtengo wake ndi wotsika, koma chophimba chomwe chimakonzedwa ndi njira yophikira burashi ndi chofooka pamodzi ndi substrate, kufanana kwa chophimbacho ndi koipa, chophimbacho ndi chopyapyala ndipo kukana kwa okosijeni ndi kochepa, ndipo njira zina zimafunika kuti zithandizire.
Njira yopopera madzi m'magazi:
Njira yopopera madzi a plasma makamaka ndi kupopera zinthu zopangira zosungunuka kapena zosungunuka pang'ono pamwamba pa graphite matrix ndi mfuti ya plasma, kenako n’kuzilimbitsa ndikugwirizana kuti zikhale zokutira. Njirayi ndi yosavuta kugwiritsa ntchito ndipo imatha kukonza zokutira za silicon carbide zokhuthala, koma zokutira za silicon carbide zomwe zakonzedwa ndi njira imeneyi nthawi zambiri zimakhala zofooka kwambiri ndipo zimapangitsa kuti pakhale kukana kofooka kwa okosijeni, choncho nthawi zambiri zimagwiritsidwa ntchito pokonzekera zokutira za SiC kuti ziwongolere mtundu wa zokutirazo.
Njira ya gel-sol:
Njira ya gel-sol makamaka ndi yokonzekera yankho la sol lomwe limaphimba pamwamba pa matrix, kuumitsa kukhala gel kenako n’kutentha kuti pakhale chophimba. Njirayi ndi yosavuta kugwiritsa ntchito ndipo ndi yotsika mtengo, koma chophimba chomwe chimapangidwa chili ndi zofooka zina monga kukana kutentha pang’ono komanso kusweka kosavuta, kotero sichingagwiritsidwe ntchito kwambiri.
Mankhwala a Mpweya (CVR):
CVR imapanga makamaka chophimba cha SiC pogwiritsa ntchito ufa wa Si ndi SiO2 kuti ipange nthunzi ya SiO2 kutentha kwambiri, ndipo zinthu zingapo zimachitika pamwamba pa chinthu cha C. Chophimba cha SiC chomwe chimakonzedwa ndi njira iyi chimalumikizidwa kwambiri ndi chinthucho, koma kutentha kwa reaction kumakhala kokwera ndipo mtengo wake ndi wokwera.
Kutaya Nthunzi ya Mankhwala (CVD):
Pakadali pano, CVD ndiye ukadaulo waukulu wokonzekera chophimba cha SiC pamwamba pa substrate. Njira yayikulu ndi mndandanda wa zochitika zakuthupi ndi zamakemikolo za zinthu zoyambitsa mpweya pamwamba pa substrate, ndipo potsiriza chophimba cha SiC chimakonzedwa mwa kuika pamwamba pa substrate. Chophimba cha SiC chokonzedwa ndi ukadaulo wa CVD chimalumikizidwa kwambiri pamwamba pa substrate, zomwe zingathandize bwino kukana okosijeni ndi kukana kwa ablative kwa zinthu zoyambitsa, koma nthawi yoikamo ya njira iyi ndi yayitali, ndipo mpweya woyambitsa uli ndi mpweya woopsa.
Msika wa SiC wokhala ndi graphite yophimbidwa ndi SiC
Pamene opanga akunja anayamba msanga, anali ndi mwayi woonekera bwino komanso anali ndi gawo lalikulu pamsika. Padziko lonse lapansi, ogulitsa akuluakulu a SiC coated graphite base ndi Dutch Xycard, Germany SGL Carbon (SGL), Japan Toyo Carbon, United States MEMC ndi makampani ena, omwe kwenikweni ali pamsika wapadziko lonse lapansi. Ngakhale kuti China yadutsa muukadaulo wofunikira kwambiri wa kukula kwa SiC coating pamwamba pa graphite matrix, graphite matrix yapamwamba kwambiri imadalirabe German SGL, Japan Toyo Carbon ndi mabizinesi ena, graphite matrix yoperekedwa ndi mabizinesi am'nyumba imakhudza moyo wautumiki chifukwa cha kutentha kwa mpweya, elastic modulus, rigid modulus, lattice defects ndi mavuto ena abwino. Zipangizo za MOCVD sizingakwaniritse zofunikira pakugwiritsa ntchito SiC coated graphite base.
Makampani opanga ma semiconductor ku China akukula mofulumira, chifukwa cha kuwonjezeka pang'onopang'ono kwa kuchuluka kwa zida za MOCVD epitaxial, komanso kukulitsa ntchito zina, msika wamtsogolo wa zinthu zopangidwa ndi graphite wokhala ndi SiC ukuyembekezeka kukula mofulumira. Malinga ndi kuyerekezera koyambirira kwa mafakitale, msika wa graphite wamkati udzapitirira 500 miliyoni yuan m'zaka zingapo zikubwerazi.
SiC coated graphite base ndiye gawo lalikulu la zida zopangira ma semiconductor, kudziwa bwino ukadaulo wofunikira kwambiri pakupanga ndi kupanga kwake, komanso kuzindikira komwe kuli makampani onse opangira zinthu zopangira, ndikofunikira kwambiri pakuwonetsetsa kuti makampani opanga ma semiconductor aku China akukula. Gawo la maziko a graphite okhala ndi SiC m'nyumba likukulirakulira, ndipo mtundu wa malonda ukhoza kufika pamlingo wapamwamba padziko lonse lapansi posachedwa.
Nthawi yotumizira: Julayi-24-2023