ʻO ke kūkulu ʻana a me ka ʻenehana ulu o ka silikon carbide (Ⅱ)

Ka ʻehā, ʻano hoʻoili mahu kino

ʻO ke ʻano o ka lawe ʻana i ka mahu kino (PVT) i hoʻokumu ʻia mai ka ʻenehana sublimation phase vapor i hana ʻia e Lely i ka makahiki 1955. Hoʻokomo ʻia ka pauka SiC i loko o kahi paipu graphite a hoʻomehana ʻia i ka wela kiʻekiʻe e decompose a sublimate i ka pauka SiC, a laila hoʻomaha ʻia ka paipu graphite. Ma hope o ka hoʻoheheʻe ʻia ʻana o ka pauka SiC, waiho ʻia nā ʻāpana mokuahi a hoʻoheheʻe ʻia i loko o nā kristal SiC a puni ka paipu graphite. ʻOiai paʻakikī kēia ala e loaʻa ai nā kristal hoʻokahi SiC nui, a paʻakikī ke kaʻina hana deposition i ka paipu graphite, hāʻawi ia i nā manaʻo no nā mea noiʻi ma hope.
Ym Terairov et al. ma Rūsia ua hoʻokomo i ka manaʻo o nā hua kristal ma kēia kumu, a hoʻoponopono i ka pilikia o ke ʻano aniani ʻole a me ke kūlana nucleation o nā kristal SiC. Ua hoʻomau ka poʻe noiʻi ma hope i ka hoʻomaikaʻi ʻana a hoʻomohala i ke ʻano o ka lawe ʻana i ke kinoea kino (PVT) i ka hoʻohana ʻana i nā ʻoihana i kēia lā.

ʻO ke ʻano o ka ulu ʻana o ka kristal SiC mua loa, ʻo ke ʻano o ka hoʻololi ʻana i ka mahu kino ke ala ulu nui loa no ka ulu ʻana o ka kristal SiC. Ke hoʻohālikelike ʻia me nā ʻano hana ʻē aʻe, he haʻahaʻa ko ke ala no nā mea ulu ulu, ke kaʻina hana ulu maʻalahi, ka mana ikaika, hoʻomohala piha a me ka noiʻi, a ua ʻike i ka noi ʻoihana. Hōʻike ʻia ke ʻano o ka kristal i ulu ʻia e ke ʻano PVT koʻikoʻi o kēia manawa ma ke kiʻi.

Hiki ke hoʻomalu ʻia nā māla wela axial a me ka radial ma ke kāohi ʻana i nā kūlana insulation thermal waho o ka graphite crucible. Hoʻokomo ʻia ka pauka SiC ma lalo o ka pahu graphite me kahi mahana kiʻekiʻe, a ua hoʻopaʻa ʻia ke aniani hua SiC ma luna o ka graphite crucible me kahi haʻahaʻa haʻahaʻa. ʻO ka mamao ma waena o ka pauda a me ka ʻanoʻano ke hoʻomalu ʻia he ʻumi millimeters e pale aku i ka pilina ma waena o ke aniani hoʻokahi e ulu ana a me ka pauda. ʻO ka gradient mahana ma ka laulā o 15-35 ℃/cm. Mālama ʻia kahi kinoea inert o 50-5000 Pa i loko o ka umu e hoʻonui ai i ka convection. Ma kēia ala, ma hope o ka hoʻomehana ʻia ʻana o ka pauka SiC i 2000-2500 ℃ e ka hoʻomehana induction, e hoʻoheheʻe ʻia ka pauka SiC a hoʻoheheʻe ʻia i loko o Si, Si2C, SiC2 a me nā mea mahu, a lawe ʻia i ka hopena o ka hua me ka convection kinoea, a Hoʻopili ʻia ke aniani SiC ma luna o ke aniani hua no ka hoʻokō ʻana i ka ulu aniani hoʻokahi. ʻO kona ulu ulu maʻamau he 0.1-2mm / h.

ʻO ke kaʻina hana PVT e kālele ana i ka mana o ka ulu ʻana o ka mahana, ka gradient mahana, ka ulu ʻana o ka ʻili, ka ʻili o ka ʻili a me ke kaomi ulu ʻana, ʻo kona pōmaikaʻi ʻo ia ke ʻano o ke kaʻina hana, maʻalahi nā mea maka, haʻahaʻa ke kumukūʻai, akā ke kaʻina ulu o He paʻakikī ka nānā ʻana i ke ʻano PVT, ka nui o ka ulu ʻana o ke aniani o 0.2-0.4mm/h, paʻakikī ke ulu i nā kristal me ka mānoanoa nui (> 50mm). Ma hope o nā ʻumi makahiki o ka hoʻomau mau ʻana, ʻo ka mākeke o kēia manawa no nā wafers substrate SiC i ulu ʻia e ke ʻano PVT ua nui loa, a hiki i ka puka makahiki o nā wafers substrate SiC hiki ke hiki i nā haneli haneli o nā wafers, a ke loli mālie nei kona nui mai 4 iniha a 6 iniha. , a ua hoʻomohala i 8 iniha o nā laʻana substrate SiC.

 

Ka lima,ʻO ke ʻano o ka hoʻomoe ʻana i ka mahu kemika kiʻekiʻe

 

ʻO ka High Temperature Chemical Vapor Deposition (HTCVD) kahi hana i hoʻomaikaʻi ʻia e pili ana i ka Chemical Vapor Deposition (CVD). Ua noi mua ʻia ke ʻano hana ma 1995 e Kordina et al., Linkoping University, Sweden.
Hōʻike ʻia ke kiʻikuhi ulu ulu ma ke kiʻi:

Hiki ke hoʻomalu ʻia nā māla wela axial a me ka radial ma ke kāohi ʻana i nā kūlana insulation thermal waho o ka graphite crucible. Hoʻokomo ʻia ka pauka SiC ma lalo o ka pahu graphite me kahi mahana kiʻekiʻe, a ua hoʻopaʻa ʻia ke aniani hua SiC ma luna o ka graphite crucible me kahi haʻahaʻa haʻahaʻa. ʻO ka mamao ma waena o ka pauda a me ka ʻanoʻano ke hoʻomalu ʻia he ʻumi millimeters e pale aku i ka pilina ma waena o ke aniani hoʻokahi e ulu ana a me ka pauda. ʻO ka gradient mahana ma ka laulā o 15-35 ℃/cm. Mālama ʻia kahi kinoea inert o 50-5000 Pa i loko o ka umu e hoʻonui ai i ka convection. Ma kēia ala, ma hope o ka hoʻomehana ʻia ʻana o ka pauka SiC i 2000-2500 ℃ e ka hoʻomehana induction, e hoʻoheheʻe ʻia ka pauka SiC a hoʻoheheʻe ʻia i loko o Si, Si2C, SiC2 a me nā mea mahu, a lawe ʻia i ka hopena o ka hua me ka convection kinoea, a Hoʻopili ʻia ke aniani SiC ma luna o ke aniani hua no ka hoʻokō ʻana i ka ulu aniani hoʻokahi. ʻO kona ulu ulu maʻamau he 0.1-2mm / h.

ʻO ke kaʻina hana PVT e kālele ana i ka mana o ka ulu ʻana o ka mahana, ka gradient mahana, ka ulu ʻana o ka ʻili, ka ʻili o ka ʻili a me ke kaomi ulu ʻana, ʻo kona pōmaikaʻi ʻo ia ke ʻano o ke kaʻina hana, maʻalahi nā mea maka, haʻahaʻa ke kumukūʻai, akā ke kaʻina ulu o He paʻakikī ka nānā ʻana i ke ʻano PVT, ka nui o ka ulu ʻana o ke aniani o 0.2-0.4mm/h, paʻakikī ke ulu i nā kristal me ka mānoanoa nui (> 50mm). Ma hope o nā ʻumi makahiki o ka hoʻomau mau ʻana, ʻo ka mākeke o kēia manawa no nā wafers substrate SiC i ulu ʻia e ke ʻano PVT ua nui loa, a hiki i ka puka makahiki o nā wafers substrate SiC hiki ke hiki i nā haneli haneli o nā wafers, a ke loli mālie nei kona nui mai 4 iniha a 6 iniha. , a ua hoʻomohala i 8 iniha o nā laʻana substrate SiC.

 

Ka lima,ʻO ke ʻano o ka hoʻomoe ʻana i ka mahu kemika kiʻekiʻe

 

ʻO ka High Temperature Chemical Vapor Deposition (HTCVD) kahi hana i hoʻomaikaʻi ʻia e pili ana i ka Chemical Vapor Deposition (CVD). Ua noi mua ʻia ke ʻano hana ma 1995 e Kordina et al., Linkoping University, Sweden.
Hōʻike ʻia ke kiʻikuhi ulu ulu ma ke kiʻi:

Ke ulu ʻia ka kristal SiC ma ke kaʻina hana wai, hōʻike ʻia ka mahana a me ka hoʻohele convection i loko o ka hopena kōkua ma ke kiʻi:

Hiki ke ʻike ʻia ʻoi aku ka kiʻekiʻe o ka mahana ma kahi kokoke i ka paia crucible i loko o ka hoʻonā kōkua, ʻoiai ʻoi aku ka haʻahaʻa o ka mahana ma ke aniani hua. I ka wā o ka ulu ʻana, hāʻawi ka graphite crucible i ke kumu C no ka ulu aniani. Ma muli o ke kiʻekiʻe o ka mahana ma ka paia crucible, nui ka solubility o C, a me ka wikiwiki o ka hoʻoheheʻe ʻana, e hoʻoheheʻe ʻia ka nui o C ma ka paia crucible e hana i kahi hopena saturated o C. ʻO kēia mau hāʻina me ka nui nui. ʻO ka C i hoʻoheheʻe ʻia e lawe ʻia i ka ʻaoʻao haʻahaʻa o nā kristal hua ma o ka convection i loko o ka hopena kōkua. Ma muli o ka haʻahaʻa haʻahaʻa o ka hopena kristal hua, e emi like ana ka solubility o ka C e pili ana, a ua lilo ka hopena C-saturated mua i ka hopena supersaturated o C ma hope o ka hoʻololi ʻana i ka hopena haʻahaʻa haʻahaʻa ma lalo o kēia ʻano. ʻO Suprataturated C i ka hoʻonā i hui pū ʻia me Si i ka hoʻonā kōkua hiki ke ulu i ka epitaxial kristal SiC ma ke aniani hua. Ke hoʻoheheʻe ʻia ka ʻāpana superforated o C, e hoʻi ka hopena i ka wela wela o ka paia crucible me ka convection, a hoʻoheheʻe hou iā C e hana i ka wai paʻa.

Hoʻopau hou ke kaʻina hana, a ulu ka SiC crystal. I ke kaʻina o ka ulu ʻana o ka wai, ʻo ka hoʻoheheʻe ʻana a me ka ua o C i ka hoʻonā he mea koʻikoʻi nui o ka holomua ulu. I mea e hōʻoia ai i ka ulu ʻana o ka kristal paʻa, pono e mālama i kahi kaulike ma waena o ka hoʻoheheʻe ʻana o C ma ka paia crucible a me ka ua ma ka hopena o ka hua. Inā ʻoi aku ka nui o ka hoʻoheheʻe ʻana o C ma mua o ka ua o C, a laila e hoʻonui mālie ʻia ka C i loko o ke aniani, a e kū mai ka nucleation o SiC. Inā ʻoi aku ka liʻiliʻi o ka hoʻoheheʻe ʻana o C ma mua o ka ua o C, e paʻakikī ka ulu ʻana o ke aniani ma muli o ka nele o ka solute.
I ka manawa like, ʻo ka lawe ʻana o C ma ka convection e pili pū i ka hāʻawi ʻana o C i ka wā ulu. I mea e ulu ai i nā kristal SiC me ka maikaʻi o ka kristal maikaʻi a me ka mānoanoa lawa, pono e hōʻoia i ke koena o nā mea ʻekolu i luna, e hoʻonui nui ai i ka paʻakikī o ka ulu ʻana o ka wai wai SiC. Eia nō naʻe, me ka hoʻomaikaʻi lohi ʻana a me ka hoʻomaikaʻi ʻana i nā ʻenehana pili a me nā ʻenehana, e hōʻike lohi ʻia nā pōmaikaʻi o ka ulu ʻana o ka wai o nā kristal SiC.
I kēia manawa, hiki ke hoʻokō ʻia ka ulu ʻana o ka wai o 2-inch SiC crystals ma Iapana, a ke kūkulu ʻia nei ka ulu ʻana o ka wai o nā kristal 4-inch. I kēia manawa, ʻaʻole i ʻike ka noiʻi kūloko pili i nā hopena maikaʻi, a pono e hahai i ka hana noiʻi kūpono.

 

Ka hiku, Nā waiwai kino a me nā kemika o nā kristal SiC

 

(1) Nā waiwai mīkini: He kiʻekiʻe kiʻekiʻe ka paʻakikī o nā kristal SiC a me ke kūpaʻa maikaʻi. Aia kona paʻakikī Mohs ma waena o 9.2 a me 9.3, a ʻo kona paʻakikī Krit ma waena o 2900 a me 3100Kg/mm2, ʻo ia ka lua o nā kristal daimana ma waena o nā mea i ʻike ʻia. Ma muli o nā waiwai mechanical maikaʻi loa o SiC, hoʻohana pinepine ʻia ka pauka SiC i ka ʻoihana ʻokiʻoki a wili paha, me ka koi makahiki a hiki i nā miliona o nā tona. E hoʻohana pū ka uhi pale ʻaʻahu ma kekahi mau mea hana i ka uhi SiC, no ka laʻana, ua haku ʻia ka uhi ʻaʻahu ʻana ma luna o kekahi mau moku kaua me ka uhi SiC.

(2) Nā waiwai wela: hiki i ka conductivity thermal o SiC ke hiki i ka 3-5 W / cm·K, ʻo ia ka 3 mau manawa o ka semiconductor kahiko Si a me 8 mau manawa o GaAs. Hiki ke hoʻokuʻu koke ʻia ka hana wela o ka mea i hoʻomākaukau ʻia e SiC, no laila ua ʻoluʻolu nā koi o nā kūlana hoʻoheheʻe wela o ka hāmeʻa SiC, a ʻoi aku ka maikaʻi no ka hoʻomākaukau ʻana i nā mea mana kiʻekiʻe. Loaʻa iā SiC nā waiwai thermodynamic paʻa. Ma lalo o nā kūlana kaomi maʻamau, e hoʻoheheʻe ʻia ʻo SiC i loko o ka mahu i loaʻa iā Si a me C ma ke kiʻekiʻe.

(3) Nā waiwai kemika: Loaʻa i ka SiC nā waiwai kemika paʻa, kūpaʻa maikaʻi i ka corrosion, a ʻaʻole e pane me kekahi waika i ʻike ʻia ma ke ana wela. Hoʻokomo ʻia ʻo SiC i ka lewa no ka manawa lōʻihi e hana mālie i kahi ʻāpana lahilahi o ka SiO2 paʻa, e pale ana i nā hopena oxidation hou aʻe. Ke piʻi ka mahana i ʻoi aku ma mua o 1700 ℃, hoʻoheheʻe ka ʻāpana lahilahi SiO2 a oxidize wikiwiki. Hiki iā SiC ke hana i ka hopena oxidation lohi me nā mea hoʻoheheʻe ʻia a i ʻole nā ​​kumu, a ʻo nā wafers SiC e ʻānai ʻia i loko o KOH a me Na2O2 i hoʻoheheʻe ʻia e ʻike i ka dislocation i nā kristal SiC.

(4) Nā waiwai uila: SiC ma ke ʻano he mea hōʻike no nā semiconductor bandgap ākea, 6H-SiC a me 4H-SiC bandgap ākea he 3.0 eV a me 3.2 eV pākahi, ʻo ia ka 3 manawa o ka Si a me 2 mau manawa o GaAs. ʻO nā mea Semi-conductor i hana ʻia me SiC he liʻiliʻi liʻiliʻi ka leakage o kēia manawa a me ka nui o ke kahua uila, no laila ua manaʻo ʻia ʻo SiC he mea kūpono no nā mea mana kiʻekiʻe. ʻO ka mobility electron saturated o SiC he 2 mau manawa kiʻekiʻe ma mua o ka Si, a loaʻa iā ia nā pōmaikaʻi maopopo i ka hoʻomākaukau ʻana i nā hāmeʻa kiʻekiʻe. Hiki ke loaʻa nā kristal SiC P-type a i ʻole N-type SiC crystals ma ka doping ʻana i nā ʻātoma haumia i loko o nā kristal. I kēia manawa, hoʻohana nui ʻia nā kristal SiC P-type e Al, B, Be, O, Ga, Sc a me nā mea ʻē aʻe, a ʻo nā kristal sic N-type ka nui o ka doped e nā N atoms. ʻO ka ʻokoʻa o ka neʻe ʻana o ka doping a me ke ʻano e loaʻa i ka hopena nui i nā waiwai kino a me nā kemika o SiC. I ka manawa like, hiki ke hoʻopaʻa ʻia ka mea lawe manuahi e ka doping pae hohonu e like me V, hiki ke hoʻonui ʻia ka resistivity, a hiki ke loaʻa ka semi-insulating SiC crystal.

(5) Nā waiwai Optical: Ma muli o ke ākea ākea ākea, ʻaʻohe kala a me ka ʻike ʻole ke aniani SiC undoped. Hōʻike nā kristal SiC doped i nā kala like ʻole ma muli o ko lākou mau waiwai like ʻole, no ka laʻana, ʻōmaʻomaʻo ʻo 6H-SiC ma hope o ka doping N; 4H-SiC ʻeleʻele. He melemele ka 15R-SiC. Hoʻopili ʻia me Al, ʻike ʻia ʻo 4H-SiC i polū. He ala intuitive e hoʻokaʻawale i ke ʻano kristal SiC ma ka nānā ʻana i ka ʻokoʻa o ke kala. Me ka noiʻi mau ʻana i nā kahua pili i ka SiC i nā makahiki he 20 i hala iho nei, ua hana ʻia nā holomua nui i nā ʻenehana pili.

 

Ka walu,Hoʻokomo i ke kūlana hoʻomohala SiC

I kēia manawa, ʻoi aku ka maikaʻi o ka ʻoihana SiC, mai nā wafers substrate, nā wafers epitaxial a hiki i ka hana ʻana i nā mea hana, ka hoʻopili ʻana, ua oʻo ke kaulahao ʻoihana holoʻokoʻa, a hiki iā ia ke hāʻawi i nā huahana pili iā SiC i ka mākeke.

He alakaʻi ʻo Cree i ka ʻoihana ulu kristal SiC me kahi kūlana alakaʻi i ka nui a me ka maikaʻi o nā wafers substrate SiC. Ke hana nei ʻo Cree i kēia manawa he 300,000 SiC substrate chips i kēlā me kēia makahiki, ʻoi aku ma mua o 80% o nā moku honua.

I Kepakemapa 2019, ua hoʻolaha ʻo Cree e kūkulu ʻo ia i kahi hale hou ma New York State, USA, e hoʻohana i ka ʻenehana kiʻekiʻe loa e hoʻonui i ka mana 200 mm anawaena a me RF SiC substrate wafers, e hōʻike ana i kāna ʻenehana hoʻomākaukau mea substrate 200 mm SiC. lilo i kanaka makua.

I kēia manawa, ʻo nā huahana koʻikoʻi o SiC substrate chips ma ka mākeke ʻo 4H-SiC a me 6H-SiC conductive a me nā ʻano semi-insulated o 2-6 iniha.
I ʻOkakopa 2015, ʻo Cree ka mea mua i hoʻomaka i ka 200 mm SiC substrate wafers no N-type a me LED, e hōʻailona ana i ka hoʻomaka ʻana o ka 8-inch SiC substrate wafers i ka mākeke.
Ma 2016, hoʻomaka ʻo Romm e kākoʻo i ka hui Venturi a ʻo ia ka mea mua i hoʻohana i ka hui IGBT + SiC SBD i loko o ke kaʻa e hoʻololi i ka hopena IGBT + Si FRD i ka inverter kuʻuna 200 kW. Ma hope o ka hoʻomaikaʻi ʻana, hoʻemi ʻia ke kaumaha o ka inverter e 2 kg a hoʻemi ʻia ka nui e 19% ʻoiai e mālama ana i ka mana like.

Ma 2017, ma hope o ka hoʻokomo hou ʻana o SiC MOS + SiC SBD, ʻaʻole i hoʻemi ʻia ke kaumaha e 6 kg, hoʻemi ʻia ka nui e 43%, a hoʻonui ʻia ka mana inverter mai 200 kW a 220 kW.
Ma hope o ka hoʻohana ʻana o Tesla i nā polokalamu SIC i nā mea hoʻohuli nui o kāna mau huahana Model 3 i 2018, ua hoʻonui wikiwiki ʻia ka hopena hōʻikeʻike, e hoʻolilo koke i ka mākeke automotive xEV i kumu o ka hauʻoli no ka mākeke SiC. Me ka hoʻohana kūleʻa ʻana o SiC, ua piʻi wikiwiki aʻe ka waiwai o ka mākeke pili.

Ka iwa,Ka hopena:

Me ka hoʻomaikaʻi mau ʻana o nā ʻenehana ʻoihana pili i ka SiC, e hoʻomaikaʻi hou ʻia kona hua a me ka hilinaʻi, e hoʻemi ʻia ke kumukūʻai o nā mea SiC, a ʻike ʻia ka hoʻokūkū mākeke o SiC. I ka wā e hiki mai ana, e hoʻohana nui ʻia nā mea SiC i nā ʻano like ʻole e like me nā kaʻa, kamaʻilio, nā mana mana, a me ka lawe ʻana, a ʻoi aku ka laulā o ka mākeke huahana, a e hoʻonui ʻia ka nui o ka mākeke, e lilo i kākoʻo nui no ka lāhui. hoʻokele waiwai.