Maitiro ekutanga eSiCKukura kwekristaro kwakakamurwa kuita sublimation uye kuora kwezvinhu zvakagadziriswa pakupisa kwakanyanya, kutakurwa kwezvinhu zvegasi pasi pekushanda kwekupisa kwakanyanya, uye kukura kwegasi pachikamu chegasi pakristaro yembeu. Zvichibva pane izvi, mukati mechikamu chekristaro makakamurwa kuita zvikamu zvitatu: nzvimbo yezvinhu zvakagadziriswa, imba yekukura uye kristaro yembeu. Muenzaniso wekufananidzira wenhamba wakatorwa zvichibva pane resistive chaiyo.SiCmichina yekukura kwekristaro imwe chete (ona Mufananidzo 1). Mukuverenga: pasi pechipfuro chemotoiri 90 mm kubva pasi pechitofu chedivi, tembiricha yepamusoro yechitofu i2100 ℃, dhayamita yechinhu chisina kugadzirwa i1000 μm, porosity i0.6, kumanikidzwa kwekukura i300 Pa, uye nguva yekukura i100 h. Ukobvu hwePG i5 mm, dhayamita yakaenzana nedhayamita yemukati yechitofu, uye iri pamusoro pe30 mm pamusoro pechinhu chisina kugadzirwa. Maitiro ekuisa pasi, carbonization, uye recrystallization yenzvimbo yezvinhu zvisina kugadzirwa anotariswa mukuverenga, uye maitiro ari pakati pePG nezvinhu zvegasi haatariswe. Maparamita epfuma ane chekuita nekuverenga anoratidzwa muTafura 1.
Mufananidzo 1. Muenzaniso wekuverenga weSimulation. (a) Muenzaniso weThermal field wekufananidzira kukura kwekristaro; (b) Kupatsanurwa kwenzvimbo yemukati ye crucible nematambudziko emuviri anoenderana nawo
Tafura 1 Mamwe ma parameter emuviri anoshandiswa mukuverenga
Mufananidzo 2(a) unoratidza kuti tembiricha yechimiro chine PG (chinotaridzwa sechimiro 1) yakakwira kupfuura yechimiro chisina PG (chinotaridzwa sechimiro 0) pasi pePG, uye yakaderera pane yechimiro 0 pamusoro pePG. Kupisa kwese kunowedzera, uye PG inoshanda semushonga wekudzivirira kupisa. Sekureva kweMifananidzo 2(b) na2(c), kudziya kweaxial neradial kwechimiro 1 munzvimbo yezvinhu zvisina kugadzirwa kudiki, kupararira kwetembiricha kwakafanana, uye sublimation yezvinhu zvakakwana. Kusiyana nenzvimbo yezvinhu zvisina kugadzirwa, Mufananidzo 2(c) unoratidza kuti kudziya kweradial pakristaro yembeu yechimiro 1 yakakura, izvo zvinogona kukonzerwa nehuwandu hwakasiyana hwemhando dzakasiyana dzekupisa, izvo zvinobatsira kristaro kukura ne convex interface. MuMufananidzo 2(d), tembiricha panzvimbo dzakasiyana mu crucible inoratidza mafambiro ari kuwedzera sezvo kukura kuri kufambira mberi, asi musiyano wetembiricha pakati pechimiro 0 nechimiro 1 unoderera zvishoma nezvishoma munzvimbo yezvinhu zvisina kugadzirwa uye unowedzera zvishoma nezvishoma muimba yekukura.
Mufananidzo 2 Kugoverwa kwekupisa uye shanduko muchikamu chinopisirwa. (a) Kugoverwa kwekupisa mukati mechikamu chinopisirwa chechimiro 0 (kuruboshwe) uye chimiro 1 (kurudyi) pa 0 awa, unit: ℃; (b) Kugoverwa kwekupisa pakati pechikamu chinopisirwa chechimiro 0 uye chimiro 1 kubva pasi pezvinhu zvisina kugadzirwa kusvika kukristaro yembeu pa 0 awa; (c) Kugoverwa kwekupisa kubva pakati kusvika kumucheto wechikamu chinopisirwa pamusoro pekristaro yembeu (A) uye pamusoro pezvinhu zvisina kugadzirwa (B), pakati (C) uye pasi (D) pa 0 awa, horizontal axis r ndiyo seed crystal radius yeA, uye rediyumu yenzvimbo yezvinhu zvisina kugadzirwa yeB~D; (d) Kuchinja kwekupisa pakati pechikamu chepamusoro (A), pamusoro pezvinhu zvisina kugadzirwa (B) uye pakati (C) yekamuri rekukura rechimiro 0 uye chimiro 1 pa 0, 30, 60, uye 100 awa.
Mufananidzo 3 unoratidza kutakurwa kwezvinhu panguva dzakasiyana muchikamu chesimbi chechimiro 0 nechimiro 1. Mwero wekuyerera kwezvinhu zvegasi munzvimbo yezvinhu zvakachekwa uye mukamuri rekukura unowedzera nekuwedzera kwenzvimbo, uye kutakurwa kwezvinhu kunoderera sezvo kukura kuri kufambira mberi. Mufananidzo 3 unoratidzawo kuti pasi pemamiriro ekufananidza, zvinhu zvakachekwa zvinotanga kuumbwa pamadziro erutivi rwesimbi uye ipapo pasi pesimbi. Pamusoro pezvo, pane kudzokororwa pamusoro pesimbi uye zvishoma nezvishoma inokora sezvo kukura kuri kufambira mberi. Mifananidzo 4(a) na4(b) inoratidza kuti mwero wekuyerera kwezvinhu mukati mesimbi wakachekwa unoderera sezvo kukura kuri kufambira mberi, uye mwero wekuyerera kwezvinhu pa100 h ungangoita 50% yenguva yekutanga; zvisinei, mwero wekuyerera wakakura pamucheto nekuda kwegraphitization yezvinhu zvakachekwa, uye mwero wekuyerera pamucheto unopfuura kagumi kupfuura mwero wekuyerera munzvimbo yepakati pa100 h; Pamusoro pezvo, mhedzisiro yePG muchimiro 1 inoita kuti mwero wekuyerera kwezvinhu munzvimbo yechinhu chisina kugadzirwa 1 uve wakaderera pane wechimiro 0. MuMufananidzo 4(c), kuyerera kwezvinhu munzvimbo yechinhu chisina kugadzirwa uye mukamuri yekukura kunopera zvishoma nezvishoma sezvo kukura kuri kufambira mberi, uye kuyerera kwezvinhu munzvimbo yechinhu chisina kugadzirwa kunoramba kuchiderera, izvo zvinokonzerwa nekuvhurwa kwenzira yekuyerera kwemhepo pamucheto wechinhu chinopfumbira uye kuvharirwa kwe recrystallization kumusoro; mukamuri yekukura, mwero wekuyerera kwezvinhu wechimiro 0 unoderera nekukurumidza mumaawa makumi matatu ekutanga kusvika 16%, uye unongoderera ne3% munguva inotevera, nepo chimiro 1 chinoramba chakadzikama mukati mekukura. Naizvozvo, PG inobatsira kudzikamisa mwero wekuyerera kwezvinhu mukamuri yekukura. Mufananidzo 4(d) unoenzanisa mwero wekuyerera kwezvinhu pamberi pekukura kwekristaro. Pakutanga uye maawa zana, kutakurwa kwezvinhu munzvimbo yekukura yechimiro 0 kwakasimba kupfuura kuri muchimiro 1, asi nguva dzose pane nzvimbo yekuyerera kwakanyanya kumucheto kwechimiro 0, izvo zvinotungamira mukukura kwakanyanya kumucheto. Kuvapo kwePG muchimiro 1 kunonyatsodzivisa chiitiko ichi.
Mufananidzo 3 Kuyerera kwezvinhu muchikamu chemoto. Kururamisa (kuruboshwe) uye mavector ekumhanya (kurudyi) ekutakura zvinhu zvegasi muzvivakwa 0 ne1 panguva dzakasiyana, velocity vector unit: m/s
Mufananidzo 4 Kuchinja kwehuwandu hwezvinhu. (a) Kuchinja kwehuwandu hwezvinhu pakati pezvinhu zvisina kugadzirwa zvechimiro 0 pa 0, 30, 60, uye 100 h, r ndiyo radius yenzvimbo yezvinhu zvisina kugadzirwa; (b) Kuchinja kwehuwandu hwezvinhu zvisina kugadzirwa pakati pezvinhu zvisina kugadzirwa zvechimiro 1 pa 0, 30, 60, uye 100 h, r ndiyo radius yenzvimbo yezvinhu zvisina kugadzirwa; (c) Kuchinja kwehuwandu hwezvinhu zvisina kugadzirwa mukati mekamuri yekukura (A, B) uye mukati mezvinhu zvisina kugadzirwa (C, D) zvezvivako 0 ne1 nekufamba kwenguva; (d) Kupararira kwehuwandu hwezvinhu pedyo nepamusoro pekristaro yembeu yezvivako 0 ne1 pa 0 ne100 h, r ndiyo radius yekristaro yembeu.
C/Si inokanganisa kugadzikana kwekristaro uye defect density yekukura kwekristaro yeSiC. Mufananidzo 5(a) unoenzanisa kugoverwa kweC/Si ratio yezvivakwa zviviri panguva yekutanga. Chiyero cheC/Si chinodzikira zvishoma nezvishoma kubva pasi kusvika pamusoro pechinopisirwa, uye chiyero cheC/Si chechimiro 1 chinogara chakakwirira kupfuura chechimiro 0 panzvimbo dzakasiyana. Mifananidzo 5(b) na5(c) zvinoratidza kuti chiyero cheC/Si chinowedzera zvishoma nezvishoma nekukura, izvo zvine chekuita nekuwedzera kwekushisa kwemukati muchikamu chekupedzisira chekukura, kuwedzerwa kwegraphitization yezvinhu zvisina kuchena, uye kuita kwezvikamu zveSi muchikamu chegasi negraphite crucible. MuMufananidzo 5(d), chiyero cheC/Si chechimiro 0 nechimiro 1 chakasiyana zvakanyanya pasi pePG (0, 25 mm), asi chakasiyana zvishoma pamusoro pePG (50 mm), uye musiyano unowedzera zvishoma nezvishoma sezvachinosvika pakristaro. Kazhinji, chiyero cheC/Si chechimiro 1 chakakwira, izvo zvinobatsira kudzikamisa chimiro chekristaro uye kuderedza mukana wekuchinja kwechikamu.
Mufananidzo 5 Kugoverwa uye kuchinja kwechiyero cheC/Si. (a) Kugoverwa kwechiyero cheC/Si muzvigadziko zvechimiro 0 (kuruboshwe) uye chimiro 1 (kurudyi) pa 0 h; (b) Chiyero cheC/Si padaro rakasiyana kubva pamutsetse wepakati wechigadziko chechimiro 0 panguva dzakasiyana (0, 30, 60, 100 h); (c) Chiyero cheC/Si padaro rakasiyana kubva pamutsetse wepakati wechigadziko chechimiro 1 panguva dzakasiyana (0, 30, 60, 100 h); (d) Kuenzaniswa kwechiyero cheC/Si padaro rakasiyana (0, 25, 50, 75, 100 mm) kubva pamutsetse wepakati wechigadziko chechimiro 0 (mutsetse wakasimba) uye chimiro 1 (mutsetse wakapatsanurwa) panguva dzakasiyana (0, 30, 60, 100 h).
Mufananidzo 6 unoratidza shanduko mudhayamita yezvikamu uye porosity yenzvimbo dzezvinhu zvakachekwa zvezvivakwa zviviri. Mufananidzo unoratidza kuti dhayamita yezvinhu zvakachekwa inoderera uye porosity inowedzera pedyo nemadziro ekupisira, uye porosity yemucheto inoramba ichikwira uye dhayamita yezvikamu inoramba ichiderera sezvo kukura kuri kufambira mberi. Porosity yepamusoro yemucheto inenge 0.99 pa100 h, uye dhayamita yepasi yezvikamu inenge 300 μm. Dhayamita yezvikamu inowedzera uye porosity inoderera pamusoro pezvinhu zvakachekwa, zvichienderana ne recrystallization. Ukobvu hwenzvimbo ye recrystallization inowedzera sezvo kukura kuri kufambira mberi, uye saizi yezvikamu uye porosity zvinoramba zvichichinja. Dhayamita yepamusoro yezvikamu inosvika 1500 μm, uye porosity yepasi i0.13. Pamusoro pezvo, sezvo PG ichiwedzera tembiricha yenzvimbo yezvinhu zvakachekwa uye gasi supersaturation iri diki, ukobvu hwe recrystallization hwechikamu chepamusoro chezvinhu zvakachekwa chechimiro 1 hudiki, izvo zvinovandudza mwero wekushandiswa kwezvinhu zvakachekwa.
Mufananidzo 6 Shanduko mudhayamita yezvikamu (kuruboshwe) uye porosity (kurudyi) yenzvimbo yezvinhu zvakagadziriswa zvechimiro 0 uye chimiro 1 panguva dzakasiyana, dhayamita yezvikamu: μm
Mufananidzo 7 unoratidza kuti chimiro 0 chinokombama pakutanga kwekukura, izvo zvingave zvine chekuita nekuwanda kwekuyerera kwezvinhu kunokonzerwa negraphitization yemucheto wezvinhu zvisina kucheneswa. Mwero wekukombama unodzikira panguva yekukura kunotevera, izvo zvinoenderana nekuchinja kwehuwandu hwekuyerera kwezvinhu pamberi pekukura kwekristaro kwechimiro 0 muMufananidzo 4 (d). Muchimiro 1, nekuda kwemhedzisiro yePG, kristaro interface hairatidzi kukombama. Pamusoro pezvo, PG inoitawo kuti huwandu hwekukura kwechimiro 1 huve hwakaderera zvakanyanya pane hwechimiro 0. Ukobvu hwepakati hwekristaro yechimiro 1 mushure memaawa zana i68% chete yehukuru 0.
Mufananidzo 7 Kuchinja kwechimiro 0 uye chimiro 1 makristaro pa30, 60, uye 100 maawa
Kukura kwekristaro kwakaitwa pasi pemamiriro ekuita simulation yenhamba. Makristaro akakura nechimiro 0 nechimiro 1 anoratidzwa muMufananidzo 8(a) neMufananidzo 8(b), zvichiteerana. Kristaro yechimiro 0 inoratidza concave interface, ine undulations munzvimbo yepakati uye phase transition kumucheto. Kubatana kwepamusoro kunomiririra imwe nhanho yekusawirirana mukutakura kwezvinhu zvegasi-phase, uye kuitika kwephase transition kunoenderana ne low C/Si ratio. Interface yekristaro yakakura nechimiro 1 yakakombama zvishoma, hapana phase transition inowanikwa, uye ukobvu i65% yekristaro isina PG. Kazhinji, mhedzisiro yekukura kwekristaro inoenderana nemhedzisiro yesimulation, nemusiyano mukuru we radial tembiricha pa crystal interface yechimiro 1, kukura nekukurumidza pamucheto kunodzvinyirirwa, uye mwero wekufamba kwezvinhu zvese unononoka. Maitiro ese anoenderana nemhedzisiro yesimulation yenhamba.
Mufananidzo 8. Makristaro eSiC akakurira pasi pechimiro 0 uye chimiro 1.
Mhedziso
PG inobatsira pakuvandudza tembiricha yese yenzvimbo yezvinhu zvakabikwa uye kuvandudza tembiricha yeaxial neradial, zvichikurudzira kushandiswa kwesublimation nekushandiswa kwezvinhu zvakabikwa; musiyano wetembiricha yepamusoro nepasi unowedzera, uye radial gradient yepamusoro pekristaro yembeu inowedzera, izvo zvinobatsira kuchengetedza kukura kwe convex interface. Panyaya yekutakura kwemasero, kuiswa kwePG kunoderedza mwero wekutamisa huwandu hwese, mwero wekufamba kwezvinhu mukamuri yekukura ine PG unochinja zvishoma nekufamba kwenguva, uye maitiro ese ekukura anogadzikana. Panguva imwecheteyo, PG inodzivirirawo kuitika kwekutamisa kwakanyanya kwemucheto. Pamusoro pezvo, PG inowedzerawo C/Si ratio yenzvimbo yekukura, kunyanya pamucheto wepamberi we seed crystal interface, izvo zvinobatsira kuderedza kuitika kwekuchinja kwechikamu panguva yekukura. Panguva imwecheteyo, thermal insulation effect yePG inoderedza kuitika kwe recrystallization muchikamu chepamusoro chezvinhu zvakabikwa kusvika pamwero wakati. Pakukura kwekristaro, PG inoderedza mwero wekukura kwekristaro, asi chimiro chekukura chinochinjika zvakanyanya. Saka, PG inzira inoshanda yekuvandudza kukura kwemakristaro eSiC uye kugadzirisa mhando yemakristaro.
Nguva yekutumira: Chikumi-18-2024