3. Ukukhula kwefilimu ebhityileyo ye-Epitaxial
I-substrate inika umaleko wenkxaso yomzimba okanye umaleko oqhubayo wezixhobo zamandla zeGa2O3. Uluhlu olulandelayo olubalulekileyo luluhlu lwesiteshi okanye i-epitaxial layer esetyenziselwa ukuxhathisa i-voltage kunye nokuthuthwa komthwali. Ukonyusa amandla ombane wokuqhekeka kunye nokunciphisa ukunganyangeki, ubukhulu obulawulekayo kunye noxinzelelo lwedoping, kunye nomgangatho ophezulu wezinto ezifunekayo, zezinye zezinto ezifunekayo. Umgangatho ophezulu we-Ga2O3 epitaxial layers zidla ngokufakwa kusetyenziswa i-molecular beam epitaxy (MBE), i-metal organic chemical vapor deposition (MOCVD), i-halide vapor deposition (HVPE), i-pulsed laser deposition (PLD), kunye nenkungu ye-CVD esekelwe ubuchule bokubeka.
Itheyibhile 2 Ezinye iiteknoloji ze-epitaxial ezimele
3.1 MBE indlela
Itekhnoloji ye-MBE idume ngokukwazi ukukhula komgangatho ophezulu, iifilimu ze-β-Ga2O3 ezingenasiphene ezinokulawulwa yi-n-type doping ngenxa yemekobume yayo ye-vacuum ephezulu kunye nokucoceka okuphezulu kwezinto. Ngenxa yoko, iye yaba yenye yezona zinto zifundiswa ngokubanzi kwaye zinokuthengiswa nge-β-Ga2O3 itekhnoloji yokubekwa kwefilimu encinci. Ukongezelela, indlela ye-MBE iphinde yalungiselela ngempumelelo umgangatho ophezulu, i-heterostructure ephantsi-doped β- (AlXGa1-X) 2O3 / Ga2O3 ifilimu encinci. I-MBE inokubeka iliso kwisakhiwo somphezulu kunye ne-morphology ngexesha lokwenyani ngokuchaneka komgangatho we-athomu ngokusebenzisa i-reflection yamandla aphezulu e-electron diffraction (RHEED). Nangona kunjalo, iifilimu ze-β-Ga2O3 ezikhule zisebenzisa itekhnoloji ye-MBE zisajongene nemingeni emininzi, efana nezinga lokukhula eliphantsi kunye nobungakanani befilimu encinci. Uphononongo lufumanise ukuba izinga lokukhula laliku-(010)>(001)>(−201)>(100). Ngaphantsi kweemeko ezincinci ze-Ga-rich ze-650 ukuya kwi-750 ° C, i-β-Ga2O3 (010) ibonisa ukukhula okulungileyo kunye nomgangatho ococekileyo kunye nezinga eliphezulu lokukhula. Ukusebenzisa le ndlela, i-β-Ga2O3 epitaxy iphunyezwe ngempumelelo nge-RMS roughness ye-0.1 nm. β-Ga2O3 Kwimeko ye-Ga-rich, iifilimu ze-MBE ezikhuliswe kumaqondo okushisa ahlukeneyo aboniswa kumfanekiso. I-Novel Crystal Technology Inc. ivelise ngempumelelo i-epitaxially i-10 × 15mm2 i-β-Ga2O3MBE yafers. Banikezela ngekhwalithi ephezulu (010) ejoliswe kwi-β-Ga2O3 enye i-crystal substrates kunye nobukhulu be-500 μm kunye ne-XRD FWHM ngaphantsi kwe-arc imizuzwana ye-150. I-substrate yi-Sn doped okanye i-Fe doped. I-Sn-doped conductive substrate ine-concentration ye-doping ye-1E18 ukuya kwi-9E18cm−3, ngelixa i-iron-doped semi-insulating substrate ine-resistivity ephezulu kune-10E10 Ω cm.
3.2 Indlela ye-MOCVD
I-MOCVD isebenzisa i-metal organic compounds njengezinto ezihamba phambili zokukhulisa iifilimu ezibhityileyo, ngaloo ndlela zifezekisa imveliso yorhwebo enkulu. Xa ukhula i-Ga2O3 usebenzisa indlela ye-MOCVD, i-trimethylgallium (TMGa), i-triethylgallium (TEGa) kunye ne-Ga (dipentyl glycol formate) idla ngokusetyenziswa njengomthombo we-Ga, ngelixa i-H2O, i-O2 okanye i-N2O isetyenziswa njengomthombo we-oksijeni. Ukukhula kusetyenziswa le ndlela ngokubanzi kufuna amaqondo obushushu aphezulu (>800°C). Le teknoloji inamandla okufikelela kwi-concentration ye-carrier carrier kunye nokuhamba kwe-electron ephezulu kunye nokushisa okuphantsi, ngoko kubaluleke kakhulu ekuphunyezweni kwezixhobo zamandla eziphezulu ze-β-Ga2O3. Xa kuthelekiswa nendlela yokukhula kwe-MBE, i-MOCVD inenzuzo yokufikelela kumazinga aphezulu kakhulu okukhula kweefilimu ze-β-Ga2O3 ngenxa yeempawu zokukhula kobushushu obuphezulu kunye neekhemikhali.
Umzobo 7 β-Ga2O3 (010) umfanekiso we-AFM
Umzobo 8 β-Ga2O3 Ubudlelwane phakathiμ kunye nokuchasana kweshiti kulinganiswe ngeHolo kunye nobushushu
3.3 Indlela yeHVPE
I-HVPE iteknoloji ye-epitaxial ekhulile kwaye isetyenziswe ngokubanzi ekukhuleni kwe-epitaxial ye-III-V ye-semiconductors edibeneyo. I-HVPE yaziwa ngexabiso layo eliphantsi lemveliso, izinga lokukhula ngokukhawuleza, kunye nobukhulu befilimu. Kufuneka kuqatshelwe ukuba i-HVPEβ-Ga2O3 ihlala ibonisa i-rough surface morphology kunye noxinaniso oluphezulu lweziphene zomhlaba kunye nemigodi. Ngoko ke, iinkqubo zokupholisa iikhemikhali kunye noomatshini ziyafuneka ngaphambi kokuvelisa isixhobo. I-HVPE iteknoloji ye-β-Ga2O3 epitaxy ngokuqhelekileyo isebenzisa i-gaseous GaCl kunye ne-O2 njenge-precursors ukukhuthaza ukusabela kobushushu obuphezulu be-(001) β-Ga2O3 matrix. Umzobo we-9 ubonisa imeko yomhlaba kunye nezinga lokukhula kwefilimu ye-epitaxial njengomsebenzi weqondo lokushisa. Kwiminyaka yakutshanje, i-Japan's Novel Crystal Technology Inc. ifumene impumelelo ebalulekileyo yorhwebo kwi-HVPE homoepitaxial β-Ga2O3, kunye nobukhulu be-epitaxial layer ye-5 ukuya kwi-10 μm kunye nobukhulu be-wafer be-2 kunye ne-4 intshi. Ukongeza, i-20 μm engqingqwa ye-HVPE β-Ga2O3 i-homoepitaxial wafers eveliswe yi-China Electronics Technology Group Corporation nayo ingene kwinqanaba lokuthengisa.
Umzobo we-9 indlela ye-HVPE β-Ga2O3
3.4 Indlela ye-PLD
Itekhnoloji ye-PLD isetyenziswa ikakhulu ukufaka iifilimu ezintsonkothileyo ze-oxide kunye ne-heterostructures. Ngexesha lenkqubo yokukhula kwe-PLD, amandla e-photon adityaniswa kwizinto ezijoliswe kuzo ngenkqubo yokukhutshwa kwe-electron. Ngokuchaseneyo ne-MBE, amasuntswana omthombo we-PLD akhiwa ngemitha yelaser enamandla kakhulu (> 100 eV) kwaye emva koko afakwe kwi-substrate eshushu. Nangona kunjalo, ngexesha lenkqubo yokukhupha, ezinye iinqununu eziphezulu zamandla ziza kuchaphazela ngokuthe ngqo umgangatho wezinto eziphathekayo, ukudala iziphene zamanqaku kwaye ngaloo ndlela zinciphisa umgangatho wefilimu. Ngokufana nendlela ye-MBE, i-RHEED ingasetyenziselwa ukubeka iliso kwisakhiwo sobuso kunye ne-morphology yezinto eziphathekayo ngexesha langempela ngexesha le-PLD β-Ga2O3 inkqubo yokubeka, evumela abaphandi ukuba bafumane ngokuchanekileyo ulwazi lokukhula. Indlela ye-PLD ilindeleke ukuba ikhulise iifilimu ze-β-Ga2O3 eziqhuba kakhulu, okwenza kube isisombululo soqhagamshelwano se-ohmic esilungisiweyo kwizixhobo zamandla ze-Ga2O3.
Umfanekiso we-10 AFM umfanekiso weSi doped Ga2O3
3.5 Indlela ye-MIST-CVD
I-MIST-CVD yitekhnoloji yohlumo lwefilim oluncinci olulula nolunexabiso eliphantsi. Le ndlela ye-CVD ibandakanya ukusabela kokutshiza i-atomized precursor kwi-substrate ukuphumeza ukubekwa kwefilim ebhityileyo. Nangona kunjalo, ukuza kuthi ga ngoku, i-Ga2O3 ekhule kusetyenziswa i-CVD yenkungu isenayo iipropathi ezilungileyo zombane, ezishiya indawo eninzi yokuphucula kunye nokwenza ngcono kwixesha elizayo.
Ixesha lokuposa: May-30-2024