1. Chiyambi
Ngakhale kuti pakhala kafukufuku wa zaka zambiri, heteroepitaxial 3C-SiC yomwe imamera pa silicon substrates sinafikebe pamlingo wokwanira wa kristalo wogwiritsidwa ntchito pamagetsi a mafakitale. Kukula kumachitika nthawi zambiri pa Si(100) kapena Si(111), iliyonse imabweretsa zovuta zosiyanasiyana: madera otsutsana ndi gawo la (100) ndi kusweka kwa (111). Ngakhale mafilimu ozikidwa pa [111] akuwonetsa makhalidwe abwino monga kuchepa kwa chilema, mawonekedwe abwino a pamwamba, ndi kupsinjika pang'ono, njira zina monga (110) ndi (211) sizikuphunziridwa mokwanira. Deta yomwe ilipo ikusonyeza kuti mikhalidwe yabwino yokulira ikhoza kukhala yolunjika, zomwe zimapangitsa kuti kufufuza mwadongosolo kukhale kovuta. Chodziwika bwino ndi chakuti, kugwiritsa ntchito ma substrates a higher-Miller-index Si (monga, (311), (510)) a 3C-SiC heteroepitaxy sikunanenedwepo, zomwe zimasiya malo ofunikira ofufuza pa njira zokulira zomwe zimadalira kulunjika.
2. Kuyesera
Zigawo za 3C-SiC zinaikidwa kudzera mu mpweya wa vapor wa atmospheric-pressure chemical vapor deposition (CVD) pogwiritsa ntchito mpweya woyambira wa SiH4/C3H8/H2. Zigawozo zinali ma wafer a Si 1 cm² okhala ndi ma directions osiyanasiyana: (100), (111), (110), (211), (311), (331), (510), (553), ndi (995). Zigawo zonse zinali pa-axis kupatula (100), pomwe ma wafer odulidwa a 2° adayesedwanso. Kuyeretsa koyambirira kwa kukula kunaphatikizapo kuchotsa mafuta mu methanol. Njira yokulira inali kuchotsa oxide yachilengedwe kudzera mu H2 annealing pa 1000°C, kutsatiridwa ndi njira yokhazikika ya magawo awiri: carburization kwa mphindi 10 pa 1165°C ndi 12 sccm C3H8, kenako epitaxy kwa mphindi 60 pa 1350°C (C/Si ratio = 4) pogwiritsa ntchito 1.5 sccm SiH4 ndi 2 sccm C3H8. Kukula kulikonse kunaphatikizapo njira zinayi kapena zisanu zosiyana za Si, ndi wafer imodzi (100) yowunikira.
3. Zotsatira ndi Kukambirana
Kapangidwe ka zigawo za 3C-SiC zomwe zimamera pa zinthu zosiyanasiyana za Si (Chithunzi 1) kanawonetsa mawonekedwe ndi kuuma kwa pamwamba. M'mawonekedwe, zitsanzo zomwe zimamera pa Si(100), (211), (311), (553), ndi (995) zinkaoneka ngati galasi, pomwe zina zinali kuyambira mkaka ((331), (510)) mpaka kuzizira ((110), (111)). Malo osalala kwambiri (omwe akuwonetsa kapangidwe kabwino kwambiri) adapezeka pa zinthu za (100)2° ndi (995). Chodabwitsa n'chakuti, zigawo zonse sizinasweke pambuyo pozizira, kuphatikizapo 3C-SiC(111) yomwe nthawi zambiri imakhala ndi nkhawa. Kukula kochepa kwa zitsanzo mwina kunaletsa kusweka, ngakhale zitsanzo zina zidawonetsa kupendekera (30-60 μm kuchoka pakati kupita m'mphepete) zomwe zimawoneka pogwiritsa ntchito maikulosikopu owonera pa kukula kwa 1000× chifukwa cha kupsinjika kwa kutentha komwe kwasonkhanitsidwa. Zigawo zopindika kwambiri zomwe zimakula pa Si(111), (211), ndi (553) substrates zimasonyeza mawonekedwe opindika omwe akusonyeza kupsinjika kwa mphamvu, zomwe zimafuna ntchito yowonjezera yoyesera komanso yongopeka kuti igwirizane ndi mawonekedwe a kristalographic.
Chithunzi 1 chikufotokoza mwachidule zotsatira za XRD ndi AFM (kusanthula pa 20×20 μ m2) za zigawo za 3C-SC zomwe zakula pa ma substrates a Si okhala ndi njira zosiyanasiyana.
Zithunzi za atomiki force microscopy (AFM) (Chithunzi 2) zinatsimikizira kuwona kwa kuwala. Ma root-mean-square (RMS) amatsimikizira malo osalala kwambiri pa (100)2° off ndi (995) substrates, okhala ndi mapangidwe ofanana ndi tirigu okhala ndi miyeso ya 400-800 nm lateral. Gawo lomera (110) linali lovuta kwambiri, pomwe mawonekedwe ataliatali ndi/kapena ofanana okhala ndi malire akuthwa nthawi zina adawonekera m'malo ena ((331), (510)). Kusanthula kwa X-ray diffraction (XRD) θ-2θ (komwe kwafotokozedwa mu Gome 1) kunawonetsa heteroepitaxy yopambana ya substrates ya lower-Miller-index, kupatula Si(110) yomwe idawonetsa 3C-SiC(111) ndi (110) peaks yosonyeza polycrystallinity. Kusakaniza uku kwanenedwa kale za Si(110), ngakhale maphunziro ena adawona 3C-SiC yapadera (111) yolunjika, zomwe zikusonyeza kuti kukonza bwino kukula ndikofunikira kwambiri. Pa ma Miller indices ≥5 ((510), (553), (995)), palibe ma XRD peaks omwe adapezeka mu standard θ-2θ configuration popeza ma high-index planes awa sakusiyana mu geometry iyi. Kusowa kwa ma low-index 3C-SiC peaks (monga, (111), (200)) kumatanthauza kukula kwa single-crystalline, komwe kumafuna kuti chitsanzo chitembenuke kuti chizindikire diffraction kuchokera ku ma low-index planes.
Chithunzi 2 chikuwonetsa kuwerengera kwa ngodya ya ndege mkati mwa kapangidwe ka kristalo ka CFC.
Ma ngodya owerengedwa a crystallographic pakati pa mapulaneti apamwamba ndi otsika (Gome 2) adawonetsa kusalunjika kwakukulu (>10°), zomwe zikufotokoza kusakhalapo kwawo mu ma scans okhazikika a θ-2θ. Chifukwa chake, kusanthula kwa chithunzi cha pole kunachitika pa chitsanzo cha (995) chifukwa cha mawonekedwe ake osazolowereka a granular (mwina kuchokera ku kukula kwa columnar kapena twinning) ndi kukhwima kochepa. Zifaniziro za (111) za pole (Chithunzi 3) kuchokera ku substrate ya Si ndi 3C-SiC layer zinali zofanana kwambiri, kutsimikizira kukula kwa epitaxial popanda twinning. Malo apakati adawonekera pa χ≈15°, zofanana ndi ngodya ya (111)-(995). Madontho atatu ofanana ndi ofanana adawonekera pamalo omwe amayembekezeredwa (χ=56.2°/φ=269.4°, χ=79°/φ=146.7° ndi 33.6°), ngakhale malo ofooka osayembekezeredwa pa χ=62°/φ=93.3° amafunika kufufuza kwina. Ubwino wa kristalo, womwe umayesedwa kudzera mu m'lifupi mwa malo mu φ-scans, ukuwoneka kuti ndi wabwino, ngakhale kuti kuyeza kwa curve yozungulira ndikofunikira kuti muyesedwe. Ziwerengero za pole za zitsanzo za (510) ndi (553) zidakalipobe kuti zitsimikizire mtundu wawo wa epitaxial.
Chithunzi 3 chikuwonetsa chithunzi cha XRD peak chojambulidwa pa chitsanzo cha (995) cholunjika, chomwe chikuwonetsa mapulaneti (111) a Si substrate (a) ndi 3C-SiC layer (b).
4. Mapeto
Kukula kwa Heteroepitaxial 3C-SiC kunapambana pa ma Si orientation ambiri kupatula (110), omwe adapereka zinthu za polycrystalline. Si(100)2° off ndi (995) substrates zidapanga zigawo zosalala kwambiri (RMS <1 nm), pomwe (111), (211), ndi (553) zidawonetsa kupendekera kwakukulu (30-60 μm). Ma High-index substrates amafunikira XRD characterization yapamwamba (monga, pole figures) kuti atsimikizire epitaxy chifukwa cha θ-2θ peaks zomwe sizilipo. Ntchito yopitilira ikuphatikizapo kuyeza kwa rocking curve, kusanthula kwa Raman stress, ndi kukulitsa ma high-index orientation ena kuti amalize kafukufukuyu wofufuza.
Monga wopanga wolumikizidwa molunjika, XKH imapereka ntchito zokonzedwa mwaluso zokhala ndi magawo ambiri a silicon carbide substrates, zomwe zimapereka mitundu yokhazikika komanso yapadera kuphatikiza 4H/6H-N, 4H-Semi, 4H/6H-P, ndi 3C-SiC, zomwe zimapezeka mu mainchesi kuyambira 2 mpaka 12. Ukatswiri wathu woyambira mpaka kumapeto pakukula kwa kristalo, kukonza molondola, komanso kutsimikizira khalidwe zimatsimikizira mayankho okonzedwa bwino amagetsi amphamvu, RF, ndi mapulogalamu atsopano.
Nthawi yotumizira: Ogasiti-08-2025