Ntụpọ akụkụ atọ
Njehie triangle bụ ntụpọ morphological kacha egbu egbu na oyi akwa epitaxial SiC. Ọtụtụ akụkọ akwụkwọ egosila na nhazi nke ntụpọ triangle metụtara ụdị kristal 3C. Agbanyeghị, n'ihi usoro uto dị iche iche, ọdịdị nke ọtụtụ ntụpọ triangle n'elu oyi akwa epitaxial dị nnọọ iche. Enwere ike kewaa ya n'ụdị ndị a:
(1) E nwere ntụpọ akụkụ atọ nwere nnukwu ihe dị n'elu ya
Ụdị ntụpọ triangle a nwere nnukwu ihe gbara okirikiri n'elu, nke ihe ndị na-ada ada n'oge usoro uto nwere ike ịkpata. Enwere ike ịhụ obere mpaghara triangle nwere elu siri ike n'ala site na vertex a. Nke a bụ n'ihi na n'oge usoro epitaxial, a na-emepụta akwa 3C-SiC abụọ dị iche iche n'usoro n'akụkụ triangle ahụ, nke a na-etinye akwa mbụ na interface ma na-eto site na usoro nzọụkwụ 4H-SiC. Ka ọkpụrụkpụ nke oyi akwa epitaxial na-abawanye, oyi akwa nke abụọ nke nucleates polytype 3C na-eto ma na-eto n'oghere triangle pere mpe, mana usoro uto 4H anaghị ekpuchi mpaghara polytype 3C kpamkpam, na-eme ka mpaghara oghere V nke 3C-SiC ka a na-ahụ anya nke ọma.
(2) E nwere obere ihe dị iche iche n'elu ya na ntụpọ atọ nwere elu siri ike
Mkpụrụ ndị dị n'akụkụ nke ụdị ntụpọ triangle a pere mpe nke ukwuu, dịka egosiri na Foto 4.2. Ọtụtụ mpaghara triangle ahụ na-ekpuchi site na usoro nzọụkwụ nke 4H-SiC, ya bụ, oyi akwa 3C-SiC dum dị n'okpuru oyi akwa 4H-SiC. Naanị usoro uto nke 4H-SiC ka a na-ahụ n'elu ntụpọ triangle ahụ, mana usoro ndị a buru ibu karịa usoro uto kristal 4H nkịtị.
(3) Nsogbu akụkụ atọ nwere elu dị ire ụtọ
Ụdị ntụpọ triangle a nwere ọdịdị elu dị nro, dịka egosiri na Foto 4.3. Maka ntụpọ triangle dị otú ahụ, a na-ekpuchi oyi akwa 3C-SiC site na usoro nzọụkwụ nke 4H-SiC, ụdị kristal 4H dị n'elu na-eto nke ọma ma na-adị nro.
Nsogbu olulu epitaxial
Oghere Epitaxial (Ogige) bụ otu n'ime ntụpọ ọdịdị elu kachasị, a na-egosikwa ọdịdị elu na nhazi ha na Foto 4.4. Ebe olulu nchara nke na-adịghị arụ ọrụ (TD) a hụrụ mgbe e tinyere KOH n'azụ ngwaọrụ ahụ nwere njikọ doro anya na ebe olulu epitaxial dị tupu nkwadebe ngwaọrụ ahụ, na-egosi na nhazi nke ntụpọ oghere epitaxial metụtara mwepụ eriri.
ntụpọ karọt
Ntụpọ karọt bụ ntụpọ elu a na-ahụkarị na oyi akwa epitaxial 4H-SiC, a na-egosikwa ụdị ha na eserese 4.5. A kọrọ na ntụpọ karọt na-etolite site na njikọ nke ntụpọ Franconian na prismatic stacking dị na basal plane jikọtara site na mwepụ dị ka nzọụkwụ. A kọkwara na nhazi nke ntụpọ karọt metụtara TSD na substrate. Tsuchida H. et al. chọpụtara na njupụta nke ntụpọ karọt na oyi akwa epitaxial kwekọrọ na njupụta nke TSD na substrate. Site na iji onyonyo ọdịdị elu tupu na mgbe uto epitaxial gasịrị, enwere ike ịchọta ntụpọ karọt niile a hụrụ ka ha dabara na TSD na substrate. Wu H. et al. jiri njirimara ule Raman scattering chọpụta na ntụpọ karọt enweghị ụdị kristal 3C, kama ọ bụ naanị ụdị polytype 4H-SiC.
Mmetụta nke ntụpọ triangle na njirimara ngwaọrụ MOSFET
Foto 4.7 bụ histogram nke nkesa ọnụọgụgụ nke njirimara ise nke ngwaọrụ nwere ntụpọ triangular. Ahịrị ntụpọ anụnụ anụnụ bụ ahịrị nkewa maka mmebi njirimara ngwaọrụ, ahịrị ntụpọ uhie bụ ahịrị nkewa maka ọdịda ngwaọrụ. Maka ọdịda ngwaọrụ, ntụpọ triangular nwere nnukwu mmetụta, ọnụego ọdịda dịkwa karịa 93%. Nke a bụ isi ihe kpatara ya bụ mmetụta nke ntụpọ triangular na njirimara ntapu azụ nke ngwaọrụ. Ruo 93% nke ngwaọrụ nwere ntụpọ triangular emeela ka ntapu azụ dịkwuo elu. Na mgbakwunye, ntụpọ triangular nwekwara mmetụta dị ukwuu na njirimara ntapu ọnụ ụzọ ámá, yana ọnụego mbibi nke 60%. Dịka egosiri na Tebụl 4.2, maka mbibi voltaji oke na mbibi njirimara diode ahụ, mmetụta nke ntụpọ triangular dị obere, oke mbibi dịkwa 26% na 33% n'otu n'otu. N'ihe gbasara ime ka mmụba na mgbochi na-abawanye, mmetụta nke ntụpọ triangular adịghị ike, oke mbibi dịkwa ihe dị ka 33%.
Mmetụta nke ntụpọ olulu epitaxial na njirimara ngwaọrụ MOSFET
Foto 4.8 bụ histogram nke nkesa ọnụọgụgụ nke njirimara ise nke ngwaọrụ nwere ntụpọ olulu epitaxial. Ahịrị ntụpọ anụnụ anụnụ bụ ahịrị nkewa maka mmebi njirimara ngwaọrụ, ahịrị ntụpọ uhie bụ ahịrị nkewa maka ọdịda ngwaọrụ. Enwere ike ịhụ site na nke a na ọnụọgụgụ ngwaọrụ nwere ntụpọ olulu epitaxial na ihe nlele SiC MOSFET hà nhata ọnụọgụgụ ngwaọrụ nwere ntụpọ triangular. Mmetụta nke ntụpọ olulu epitaxial na njirimara ngwaọrụ dị iche na nke ntụpọ triangular. N'ihe gbasara ọdịda ngwaọrụ, ọnụego ọdịda nke ngwaọrụ nwere ntụpọ olulu epitaxial bụ naanị 47%. Ma e jiri ya tụnyere ntụpọ triangular, mmetụta nke ntụpọ olulu epitaxial na njirimara nkwụsị azụ na njirimara nkwụsị ọnụ ụzọ ámá nke ngwaọrụ ahụ na-ebelata nke ukwuu, yana oke mbibi nke 53% na 38% n'otu n'otu, dịka egosiri na Tebụl 4.3. N'aka nke ọzọ, mmetụta nke ntụpọ olulu epitaxial na njirimara voltaji oke, njirimara nduzi diode ahụ na iguzogide na-aga n'ihu karịrị nke ntụpọ triangular, yana oke mmebi ruru 38%.
N'ozuzu, ntụpọ abụọ dị n'ụdị morphological, ya bụ triangles na epitaxial pits, nwere mmetụta dị ukwuu na ọdịda na mmebi njirimara nke ngwaọrụ SiC MOSFET. Ịdị adị nke ntụpọ triangles bụ ihe kacha egbu egbu, yana ọnụego ọdịda dị elu ruo 93%, nke a na-egosipụtakarị dị ka mmụba dị ukwuu na mpụta azụ nke ngwaọrụ ahụ. Ngwaọrụ nwere ntụpọ olulu epitaxial nwere obere ọnụego ọdịda nke 47%. Agbanyeghị, ntụpọ olulu epitaxial nwere mmetụta dị ukwuu na voltaji njedebe nke ngwaọrụ ahụ, njirimara conduction diode ahụ na iguzogide on-resistance karịa ntụpọ triangles.
Oge ozi: Eprel-16-2024