2. Epitaxial yakaonda firimu kukura
Iyo substrate inopa tsigiro yemuviri layer kana conductive layer yeGa2O3 magetsi emagetsi. Iyo inotevera yakakosha layer ndiyo chiteshi chiteshi kana epitaxial layer inoshandiswa kupikisa voltage uye kutakura kwekutakura. Kuti uwedzere kuparara kwemagetsi uye kuderedza conduction kuramba, kudzoreka ukobvu uye doping concentration, pamwe neyakakwana yemhando yemhando, zvimwe zvinodikanwa. High quality Ga2O3 epitaxial layers inowanzoiswa pachishandiswa molecular beam epitaxy (MBE), metal organic chemical vapor deposition (MOCVD), halide vapor deposition (HVPE), pulsed laser deposition (PLD), uye fog CVD based deposition techniques.
Tafura 2 Vamwe vanomiririra epitaxial technologies
2.1 MBE nzira
MBE tekinoroji inozivikanwa nekukwanisa kwayo kukura emhando yepamusoro, isina hurema-isina β-Ga2O3 mafirimu ane inodzoreka n-mhando doping nekuda kweiyo ultra-high vacuum nharaunda uye yakakwirira kuchena kwezvinhu. Nekuda kweizvozvo, yave imwe yeakanyanya kudzidzwa uye anogona kutengeswa β-Ga2O3 yakaonda firimu deposition tekinoroji. Mukuwedzera, nzira yeMBE yakabudirirawo kugadzirira yepamusoro-soro, yakaderera-doped heterostructure β-(AlXGa1-X)2O3/Ga2O3 nhete yefirimu. MBE inogona kutarisa chimiro chepamusoro uye morphology munguva chaiyo neatomic layer chaiyo nekushandisa kuratidza yakakwira simba erekitironi diffraction (RHEED). Nekudaro, β-Ga2O3 mafirimu akakura achishandisa MBE tekinoroji achiri kutarisana nematambudziko mazhinji, senge yakaderera chiyero chekukura uye diki firimu saizi. Chidzidzo chacho chakawana kuti kuwedzera kwekukura kwaiva muhurongwa hwe (010)> (001)> (-201)> (100). Pasi peGa-rich mamiriro e650 kusvika 750 ° C, β-Ga2O3 (010) inoratidza kukura kwakakwana nepamusoro pepamusoro uye kukura kwekukura. Uchishandisa nzira iyi, β-Ga2O3 epitaxy yakabudirira kuwanikwa neRMS roughness ye0.1 nm. β-Ga2O3 Munzvimbo yeGa-rich, MBE mafirimu akakura pakupisa kwakasiyana anoratidzwa mumufananidzo. Novel Crystal Technology Inc. yakabudirira epitaxially kugadzira 10 × 15mm2 β-Ga2O3MBE mawafer. Vanopa mhando yepamusoro (010) yakanamirwa β-Ga2O3 single crystal substrates ine ukobvu hwe500 μm uye XRD FWHM pazasi 150 arc seconds. Iyo substrate ndeye Sn doped kana Fe doped. Iyo Sn-doped conductive substrate ine doping concentration ye1E18 kusvika 9E18cm−3, nepo iron-doped semi-insulating substrate ine resistivity yakakwirira kupfuura 10E10 Ω cm.
2.2 MOCVD nzira
MOCVD inoshandisa simbi organic komisheni se precursor zvinhu kukura mafirimu matete, nekudaro kuwana yakakura-yekutengesa kugadzirwa. Paunenge uchikura Ga2O3 uchishandisa nzira yeMOCVD, trimethylgallium (TMGa), triethylgallium (TEGa) uye Ga (dipentyl glycol formate) inowanzoshandiswa seGa source, nepo H2O, O2 kana N2O inoshandiswa seyo oxygen source. Kukura uchishandisa nzira iyi kunowanzoda tembiricha yepamusoro (>800°C). Iyi tekinoroji ine mukana wekuwana yakaderera mutakuri wekutarisa uye yakakwirira uye yakaderera tembiricha yekufambisa maerekitironi, saka ine kukosha kukuru pakuzadzikiswa kwepamusoro-kushanda kwemagetsi e-β-Ga2O3. Kuenzaniswa neMBE yekukura nzira, MOCVD ine mukana wekuwana yakakwirira kwazvo yekukura kwemafirimu e-β-Ga2O3 nekuda kwemaitiro ekukura kwekupisa uye maitiro emakemikari.
Mufananidzo 7 β-Ga2O3 (010) AFM mufananidzo
Mufananidzo 8 β-Ga2O3 Hukama huri pakatiμneshizha kuramba rakayerwa neHoro uye tembiricha
2.3 HVPE nzira
HVPE inokura epitaxial tekinoroji uye yakashandiswa zvakanyanya mukukura epitaxial yeIII-V komputa semiconductors. HVPE inozivikanwa nemutengo wayo wakaderera wekugadzira, mwero wekukura nekukurumidza, uye kukora kwemafirimu. Izvo zvinofanirwa kucherechedzwa kuti HVPEβ-Ga2O3 kazhinji inoratidza rough surface morphology uye yakakwirira density yekuremara kwepasi nemakomba. Naizvozvo, makemikari uye mechanical polishing maitiro anodiwa asati agadzira mudziyo. HVPE tekinoroji ye β-Ga2O3 epitaxy inowanzoshandisa gaseous GaCl uye O2 semagadzirirwo ekusimudzira kukwirisa-tembiricha reaction ye (001) β-Ga2O3 matrix. Mufananidzo 9 unoratidza mamiriro ekunze uye kukura kweiyo epitaxial firimu sebasa rekushisa. Mumakore achangopfuura, Novel Crystal Technology Inc. yekuJapan yakawana budiriro huru yekutengeserana muHVPE homoepitaxial β-Ga2O3, ine epitaxial layer makubvu e5 kusvika 10 μm uye saizi yewafer ye2 uye 4 inches. Pamusoro pezvo, 20 μm gobvu HVPE β-Ga2O3 homoepitaxial wafers anogadzirwa neChina Electronics Technology Group Corporation apindawo mudanho rekutengesa.
Mufananidzo 9 HVPE nzira β-Ga2O3
2.4 PLD nzira
PLD tekinoroji inonyanya kushandiswa kuisa yakaoma oxide mafirimu uye heterostructures. Munguva yekukura kwePLD, simba rephoton rinosanganiswa kune zvakanangwa zvinhu kuburikidza neiyo electron emission process. Kusiyana neMBE, PLD sosi zvimedu zvinoumbwa nelaser radiation ine yakanyanya simba simba (> 100 eV) uye yozoiswa pane inopisa substrate. Nekudaro, panguva yeablation process, mamwe ma-high-energy particles anozokanganisa zvakananga pamusoro pezvinhu, achigadzira mapoinzi kukanganisa uye nekudaro kuderedza kunaka kwefirimu. Zvakafanana neMBE nzira, RHEED inogona kushandiswa kutarisa chimiro chepamusoro uye morphology yezvinhu munguva chaiyo panguva yePLD β-Ga2O3 deposition process, zvichibvumira vatsvakurudzi kuti vawane ruzivo rwekukura. Iyo PLD nzira inotarisirwa kukura zvakanyanya conductive β-Ga2O3 mafirimu, zvichiita kuti ive yakagadziridzwa ohmic yekusangana mhinduro muGa2O3 magetsi emagetsi.
Mufananidzo 10 AFM mufananidzo weSi doped Ga2O3
2.5 MIST-CVD nzira
MIST-CVD iri nyore uye inodhura-inoshanda yakaonda firimu kukura tekinoroji. Iyi nzira yeCVD inosanganisira kuita kwekupfapfaidza precursor yeatomu pane substrate kuti uwane yakaonda firimu deposition. Nekudaro, kusvika parizvino, Ga2O3 yakakura ichishandisa mhute CVD ichiri kushaya yakanaka magetsi zvivakwa, izvo zvinosiya yakawanda nzvimbo yekuvandudza uye optimization mune ramangwana.
Nguva yekutumira: May-30-2024