Mai i tōna kitenga, kua aro nui te katoa ki te silicon carbide. Ko te silicon carbide he mea tito mai i te haurua o ngā ngota Si me te haurua o ngā ngota C, e honoa ana e ngā hononga covalent mā roto i ngā takirua irahiko e tohatoha ana i ngā orbital ranu sp3. I roto i te wae hanganga taketake o tana tioata kotahi, e whā ngā ngota Si kua whakaritea ki roto i te hanganga tetrahedral auau, ā, kei waenganui o te tetrahedron auau te ngota C. I tua atu, ka taea hoki te kī ko te ngota Si te pokapū o te tetrahedron, ā, ka hangaia te SiC4, te CSi4 rānei. Hanganga tetrahedral. He tino ionic te hononga covalent i roto i te SiC, ā, he tino teitei te kaha o te hononga silicon-waro, tata ki te 4.47eV. Nā te iti o te kaha hapa whakarārangi, ka ngāwari te hanga e ngā tioata silicon carbide ngā momo polytype i te wā o te tukanga tipu. Neke atu i te 200 ngā polytype e mōhiotia ana, ka taea te wehewehe ki ngā wāhanga matua e toru: cubic, hexagonal me te trigonal.
I tēnei wā, ko ngā tikanga matua mō te whakatipu i ngā tioata SiC ko te Tikanga Kawe Kohu Ā-tinana (tikanga PVT), te Whakatakotoranga Kohu Matū Pāmahana Teitei (tikanga HTCVD), te Tikanga Āhuatanga Wai, me ētahi atu. I roto i ēnei, kua pakari ake te tikanga PVT, ā, he pai ake mō te whakaputa papatipu ahumahi.
Ko te tikanga e kiia nei ko te PVT e pā ana ki te whakatakoto i ngā tioata purapura SiC ki runga i te oko, ā, ko te whakatakoto i te paura SiC hei rauemi mata ki raro i te oko. I roto i te taiao kati o te pāmahana teitei me te pēhanga iti, ka whakatōngia te paura SiC ka neke ake i raro i te mahi a te pikinga pāmahana me te rerekētanga kukū. He tikanga mō te kawe i te paura ki te taha o te tioata purapura, kātahi ka whakatōngia anō i muri i te taenga ki te āhua tino mātotoru. Ka taea e tēnei tikanga te whakatutuki i te tipu ka taea te whakahaere o te rahi tioata SiC me ngā āhua tioata motuhake.
Heoi, mā te whakamahi i te tikanga PVT hei whakatipu tioata SiC, me pupuri tonu ngā āhuatanga tipu tika i roto i te tukanga tipu mō te wā roa, ki te kore ka raru te whatunga, ka pā ki te kounga o te tioata. Heoi, ka oti te tipu o ngā tioata SiC i roto i te wāhi kati. He iti noa ngā tikanga aroturuki whai hua, ā, he maha ngā taurangi, nō reira he uaua te whakahaere tukanga.
I roto i te tukanga whakatipu tioata SiC mā te tikanga PVT, ko te aratau tipu rere taahiraa (Tipu Rere Hipanga) e kiia ana ko te tikanga matua mō te tipu pumau o te āhua tioata kotahi.
Ka pai ake te hononga o ngā ngota Si me ngā ngota C kua mimiti ki ngā ngota mata tioata i te pūwāhi piko, ka puta ai he pūngao, ka tipu, ka rere whakarara ia taahiraa ki mua. Ina nui atu te whānui o ngā taahiraa i runga i te mata tioata i te ara kore horapa o ngā adatom, ka nui pea ngā adatom e kohikohi ana, ā, ka whakangaromia e te aratau tipu moutere-ahu-rua te aratau tipu rere taahiraa, ka ngaro ngā mōhiohio hanganga tioata 4H, ka hua ake he maha ngā hapa. Nō reira, me whakatutuki te whakatikatika i ngā tawhā tukanga i te whakahaere i te hanganga taahiraa mata, kia pehi ai i te whakaputanga o ngā hapa polymorphic, kia tutuki ai te kaupapa o te whiwhi i te āhua tioata kotahi, ā, i te mutunga ka whakarite i ngā tioata kounga teitei.
Hei te tikanga whakatipu tioata SiC tuatahi i whakawhanakehia, ko te tikanga kawe kohu ā-tinana te tikanga whakatipu tino rongonui mō te whakatipu tioata SiC. Ki te whakatauritea ki ētahi atu tikanga, he iti ake ngā whakaritenga mō ngā taputapu whakatipu i tēnei tikanga, he māmā te tukanga whakatipu, he kaha te whakahaere, he rangahau whanaketanga tino hohonu, ā, kua tutuki kē te tono ahumahi. Ko te painga o te tikanga HTCVD ko te taea te whakatipu i ngā papa hiko (n, p) me ngā papa hiko-teitei, ā, ka taea te whakahaere i te kukū tāpiri kia taea ai te whakarite i te kukū kawe i roto i te papa hiko i waenga i te 3×1013~5×1019/cm3. Ko ngā ngoikoretanga ko te paepae hangarau teitei me te iti o te wahanga mākete. I te haere tonu o te pakari o te hangarau whakatipu tioata SiC wai-wāhanga, ka whakaatu i te kaha nui ki te whakatairanga i te umanga SiC katoa a muri ake nei, ā, tera pea he wāhi hou ki te whakatipu tioata SiC.
Wā tuku: Paenga-whāwhā-16-2024