Ukucatshangelwa Okubalulekile kwe-High-Quality Silicon Carbide Single Crystal Preparation

Izindlela eziyinhloko zokulungiselela ikristalu eyodwa ye-silicon zifaka: I-Physical Vapor Transport (PVT), Ukukhula Kwesixazululo Esinembewu Ephezulu (TSSG), kanye Ne-High-Temperature Chemical Vapor Deposition (HT-CVD). Phakathi kwalokhu, indlela ye-PVT yamukelwa kabanzi ekukhiqizeni izimboni ngenxa yemishini yayo elula, ukulawula kalula, kanye nemishini ephansi nezindleko zokusebenza.

Amaphuzu Abalulekile Ezobuchwepheshe Okukhula kwe-PVT Yamakristalu e-Silicon Carbide

Lapho ukhulisa amakristalu e-silicon carbide usebenzisa indlela ye-Physical Vapor Transport (PVT), lezi zici zobuchwepheshe ezilandelayo kufanele zibhekwe:

1. Ukuhlanzeka Kwezinto Ze-Graphite Egumbini Lokukhula: Okuqukethwe kokungcola ezingxenyeni ze-graphite kufanele kube ngaphansi kuka-5×10⁻⁶, kuyilapho okuqukethwe okungcolile okuzwakalayo kufanele kube ngaphansi kuka-10×10⁻⁶. Ama-elementi afana no-B no-Al kufanele agcinwe ngaphansi kuka-0.1×10⁻⁶.
2. Ukukhethwa Okulungile Kwe-Crystal Polarity Yembewu: Ucwaningo olunamandla lubonisa ukuthi ubuso be-C (0001) bufanele ukukhulisa amakristalu e-4H-SiC, kuyilapho ubuso be-Si (0001) busetshenziselwa ukukhulisa amakristalu e-6H-SiC.
3. Ukusetshenziswa kwamakristalu embewu ye-Off-Axis: Amakristalu embewu angaphandle kwe-axis angashintsha ukulinganisa kokukhula kwekristalu, anciphise amaphutha kukristalu.
4. Inqubo Yekhwalithi Ephakeme Ye-Crystal Bonding.
5. Ukugcina Ukuzinza Kwe-Crystal Growth Interface Phakathi Nomjikelezo Wokukhula.

Ubuchwepheshe obubalulekile bokukhula kwe-Silicon Carbide Crystal

1. I-Doping Technology ye-Silicon Carbide Powder
   Ukufakela i-silicon carbide powder ngenani elifanele le-Ce kungasimamisa ukukhula kwamakristalu angabodwa e-4H-SiC. Imiphumela esebenzayo ibonisa ukuthi i-Ce doping inga:

• Khulisa izinga lokukhula kwamakristalu e-silicon carbide.
• Lawula umumo wokukhula kwekristalu, ukwenze kufane futhi kube njalo.
• Cindezela ukwakheka kokungcola, unciphisa amaphutha futhi wenze kube lula ukukhiqizwa kwekristalu eyodwa kanye nekhwalithi ephezulu.
• Vimba ukugqwala okungemuva kwekristalu futhi uthuthukise isivuno sekristalu eyodwa.

• I-Axial kanye neRadial Temperature Gradient Control Technology
  I-axial temperature gradient ithinta ngokuyinhloko uhlobo lokukhula kwekristalu nokusebenza kahle. I-gradient encane kakhulu yokushisa ingaholela ekwakhekeni kwe-polycrystalline futhi inciphise amazinga okukhula. Izinga lokushisa elifanele le-axial kanye ne-radial lokushisa lisiza ukukhula ngokushesha kwekristalu ye-SiC ngenkathi igcina ikhwalithi yekristalu ezinzile.
• I-Basal Plane Dislocation (BPD) Control Technology
  Ukukhubazeka kwe-BPD kuphakama ikakhulukazi lapho ukucindezeleka kwe-shear ku-crystal kudlula ukucindezeleka okubucayi kwe-shear ye-SiC, amasistimu wokushelela asebenzayo. Njengoba ama-BPD e-perpendicular ekukhuleni kwekristalu, akheka kakhulu ngesikhathi sokukhula kwekristalu nokupholisa.
• I-Vapor Phase Composition Ratio Adjustment Technology
  Ukwandisa isilinganiso se-carbon-to-silicon endaweni yokukhula kuyisinyathelo esisebenzayo sokuzinzisa ukukhula kwekristalu eyodwa. Isilinganiso esiphezulu se-carbon-to-silicon sinciphisa ukunqwabelana kwezinyathelo ezinkulu, silondoloze ulwazi lokukhula kwekristalu lembewu, futhi kucindezela ukwakheka kwe-polytype.
• Ubuchwepheshe Bokulawula Ukucindezeleka Okuphansi
  Ukucindezeleka ngesikhathi sokukhula kwekristalu kungabangela ukugoba kwezindiza zekristalu, okuholela kukhwalithi yekristalu empofu noma ngisho nokuqhekeka. Ingcindezi ephezulu iphinda inyuse ukugudluka kwendiza ye-basal, okungase kuthinte kabi ikhwalithi yongqimba lwe-epitaxial nokusebenza kwedivayisi.

Isithombe sokuskena se-SiC wafer esingu-6-intshi

Izindlela Zokunciphisa Ingcindezi Kumakristalu:

• Lungisa ukusatshalaliswa kwenkambu yezinga lokushisa futhi ucubungule amapharamitha ukuze unike amandla ukukhula okuseduze kwekristalu elilodwa le-SiC.
• Lungiselela ukwakheka kwe-crucible ukuvumela ukukhula kwekristalu kwamahhala ngemikhawulo emincane.
• Lungisa amasu okulungisa ikristalu lembewu ukuze unciphise ukungezwani kokwanda okushisayo phakathi kwekristalu lembewu nesibambi segraphite. Indlela evamile iwukushiya igebe elingu-2 mm phakathi kwekristalu lembewu nesibambi segraphite.
• Thuthukisa izinqubo zokuthungatha ama-anneal ngokusebenzisa i-in-situ annealing, ukulungisa izinga lokushisa le-anneal nobude besikhathi ukuze ukhulule ngokugcwele ingcindezi yangaphakathi.

Amathrendi Esikhathi esizayo ku-Silicon Carbide Crystal Growth Technology

Uma ubheka phambili, ubuchwepheshe bokulungiselela ikristalu elilodwa lwe-SiC buzothuthuka ngalezi zikhombisi-ndlela ezilandelayo:

1. Ukukhula Okukhulu
   Ububanzi bekristalu eyodwa ye-silicon carbide buguqukile ukusuka kumamilimitha ambalwa ukuya ku-6-intshi, 8-intshi, kanye nosayizi abakhulu bamayintshi angu-12. Amakristalu e-SiC anobubanzi obukhulu athuthukisa ukusebenza kahle kokukhiqiza, anciphise izindleko, futhi ahlangabezane nezidingo zamadivayisi anamandla amakhulu.
2. Ukukhula Okusezingeni Eliphezulu
   Amakristalu e-SiC ekhwalithi ephezulu abalulekile kumadivayisi asebenza kahle kakhulu. Nakuba kwenziwe inqubekelaphambili enkulu, amaphutha njengamapayipi amancane, ukugudluzwa, nokungcola kusekhona, okuthinta ukusebenza nokuthembeka kwedivayisi.
3. Ukwehliswa Kwezindleko
   Izindleko eziphezulu zokulungiswa kwekristalu ye-SiC zikhawulela ukusetshenziswa kwayo emikhakheni ethile. Ukuthuthukisa izinqubo zokukhula, ukuthuthukisa ukusebenza kahle kokukhiqiza, nokunciphisa izindleko zempahla eluhlaza kungasiza ukwehlisa izindleko zokukhiqiza.
4. Ukukhula Okuhlakaniphile
   Ngokuthuthuka kwe-AI nedatha enkulu, ubuchwepheshe bokukhula kwekristalu be-SiC buzokhula busebenzisa izixazululo ezihlakaniphile. Ukuqapha nokulawula kwesikhathi sangempela kusetshenziswa izinzwa nezinhlelo ezizenzakalelayo kuzothuthukisa ukuzinza nokulawula kwenqubo. Ukwengeza, ukuhlaziya idatha enkulu kungathuthukisa imingcele yokukhula, kuthuthukise ikhwalithi yekristalu nokusebenza kahle kokukhiqiza.

Ubuchwepheshe bekhwalithi ephezulu ye-silicon carbide single crystal yokulungiselela buyinto ebalulekile ekugxilweni kwayo ocwaningweni lwempahla ye-semiconductor. Njengoba ubuchwepheshe buthuthuka, amasu okukhula kwekristalu ye-SiC azoqhubeka nokuvela, anikeze isisekelo esiqinile sezinhlelo zokusebenza kumazinga okushisa aphezulu, ama-high-frequency, kanye nezinkambu zamandla aphezulu.