1. semiconductors ọgbọ nke atọ
Emepụtara teknụzụ semiconductor ọgbọ mbụ dabere na ihe semiconductor dị ka Si na Ge. Ọ bụ ihe ndabere ihe maka mmepe nke transistor na teknụzụ sekit jikọtara ọnụ. Ihe semiconductor nke ọgbọ mbụ tọrọ ntọala maka ụlọ ọrụ eletrọnịkị na narị afọ nke 20 ma bụrụ ihe bụ isi maka teknụzụ sekit jikọtara ọnụ.
Ihe semiconductor nke ọgbọ nke abụọ gụnyere gallium arsenide, indium phosphide, gallium phosphide, indium arsenide, aluminum arsenide na ogige ternary ha. Ihe semiconductor nke ọgbọ nke abụọ bụ ntọala nke ụlọ ọrụ ozi optoelectronic. Na ndabere nke a, e mepụtala ụlọ ọrụ ndị metụtara ya dị ka ọkụ, ihe ngosi, laser, na fotovoltaics. A na-eji ha eme ihe na teknụzụ ozi nke oge a yana ụlọ ọrụ ngosi optoelectronic.
Ihe nnọchite anya ihe semiconductor ọgbọ nke atọ gụnyere gallium nitride na silicon carbide. N'ihi oghere dị obosara ha, ngwa ngwa saturation elektrọn dị elu, ịdị elu thermal conductivity, na ike mgbawa dị elu, ha bụ ihe dị mma maka ịkwadebe njupụta ike dị elu, ugboro ugboro na ngwaọrụ eletrọnịkị dị ala. N'ime ha, ngwaọrụ silicon carbide nwere uru nke njupụta ume dị elu, obere ume ike, na obere nha, ma nwee atụmanya ngwa ngwa n'ime ụgbọ ala ike ọhụrụ, fotovoltaics, ụgbọ okporo ígwè, nnukwu data na mpaghara ndị ọzọ. Ngwa Gallium nitride RF nwere uru nke ugboro dị elu, ike dị elu, bandwidth obosara, obere ike oriri na obere nha, ma nwee atụmanya ngwa ngwa na nkwukọrịta 5G, Ịntanetị nke ihe, radar agha na mpaghara ndị ọzọ. Tụkwasị na nke ahụ, a na-eji ngwaọrụ gallium nitride ike mee ihe n'ọtụtụ ebe na mpaghara obere voltaji. Na mgbakwunye, n'ime afọ ndị na-adịbeghị anya, a na-atụ anya na ihe gallium oxide na-apụta ga-emepụta nkwado teknụzụ na teknụzụ SiC na GaN dị adị, ma nwee atụmanya ngwa ngwa na mpaghara obere obere na voltaji dị elu.
E jiri ya tụnyere ihe semiconductor nke ọgbọ nke abụọ, ihe ndị na-emepụta ihe na-emepụta ihe nke atọ nwere obosara bandgap (obosara bandgap nke Si, ihe a na-ahụkarị nke ihe semiconductor nke ọgbọ mbụ, bụ ihe dịka 1.1eV, obosara bandgap nke GaAs, nke a na-ahụkarị. ihe nke ọgbọ nke abụọ semiconductor ihe, bụ ihe dị ka 1.42eV, na bandgap obosara nke GaN, a na-ahụkarị ihe onwunwe nke Ihe semiconductor nke ọgbọ nke atọ, dị n'elu 2.3eV), nguzogide radieshon siri ike, nkwụsi ike na nkwụsị ọkụ eletrik, na nguzogide okpomọkụ dị elu. Ihe semiconductor nke ọgbọ nke atọ na obosara bandgap obosara dabara adaba maka mmepụta nke radieshon na-eguzogide, ugboro ugboro, ike dị elu na ngwa ngwa ngwa ngwa eletriki. Ngwa ha na ngwa ngwa redio ugboro ugboro, LEDs, lasers, ngwaọrụ ike na mpaghara ndị ọzọ adọtala anya nke ukwuu, ha egosiwokwa atụmanya mmepe sara mbara na nkwukọrịta mkpanaka, grids smart, ụzọ ụgbọ oloko, ụgbọ ala ike ọhụrụ, ngwa elektrọn ndị ahịa, na ultraviolet na acha anụnụ anụnụ. - ngwaọrụ ọkụ ndụ ndụ [1].
Isi iyi onyonyo: CASA, Zheshang Securities Research Institute
Ọgụgụ 1 GaN ike ngwaọrụ oge nha na amụma
II GaN ihe nhazi na njirimara
GaN bụ semiconductor bandgap ozugbo. Obosara bandgap nke ihe owuwu wurtzite na ụlọ okpomọkụ dị ihe dịka 3.26eV. Ihe GaN nwere ihe owuwu kristal atọ, ya bụ wurtzite Ọdịdị, sphalerite Ọdịdị na nkume nnu nhazi. N'ime ha, ihe owuwu wurtzite bụ usoro kristal kachasị kwụsiri ike. Onyonyo 2 bụ eserese nke nhazi hexagonal wurtzite nke GaN. Ọdịdị wurtzite nke ihe GaN bụ nke ihe owuwu nwere akụkụ hexagonal. Mkpụrụ ndụ otu ọ bụla nwere atọm iri na abụọ, gụnyere 6 N atọm na 6 Ga atọm. Atọm Ga (N) ọ bụla na-etolite njikọ ya na atọm N (Ga) 4 kacha nso ma debe ya n'usoro nke ABABAB… n'akụkụ ntụzịaka [0001] [2].
Ọgụgụ 2 Ọdịdị Wurtzite GaN eserese cell kristal
III Mgbochi ndị a na-ejikarị maka GaN epitaxy
Ọ dị ka epitaxy na-arụkọ ọrụ ọnụ na mkpụrụ GaN bụ nhọrọ kacha mma maka Epitaxy GaN. Otú ọ dị, n'ihi nnukwu njikọ ike nke GaN, mgbe okpomọkụ ruru ebe agbaze nke 2500 ℃, ya kwekọrọ decomposition nrụgide bụ banyere 4.5GPa. Mgbe nrụgide nbibi dị ala karịa nrụgide a, GaN adịghị agbaze kama ọ na-agbaze ozugbo. Nke a na-eme ka teknụzụ nkwadebe mkpụrụ tozuru oke dị ka usoro Czochralski adịghị mma maka nkwadebe nke GaN otu mkpụrụ kristal, na-eme ka mkpụrụ GaN sie ike imepụta na ọnụ. Ya mere, ihe ndị a na-ejikarị eme ihe na GaN epitaxial growth bụ karịsịa Si, SiC, sapphire, wdg. [3].
Chart 3 GaN na parampat nke ihe ndị a na-ejikarị eme ihe
GaN epitaxy na sapphire
Sapphire nwere akụrụngwa kemịkalụ kwụsiri ike, dị ọnụ ala, ma nwee ntozu oke nke nnukwu ụlọ ọrụ mmepụta ihe. Ya mere, ọ ghọwo otu n'ime ihe ndị mbụ na-ejikarị eme ihe na nhazi ngwaọrụ semiconductor. Dị ka otu n'ime ihe ndị a na-ejikarị eme ihe maka GaN epitaxy, nsogbu ndị dị mkpa a ga-edozi maka sapphire substrates bụ:
✔ N'ihi nnukwu lattice mismatch n'etiti sapphire (Al2O3) na GaN (ihe dị ka 15%), njupụta ntụpọ dị na interface n'etiti oyi akwa epitaxial na mkpụrụ dị elu. Iji belata mmetụta ọjọọ ya, mkpụrụ osisi ahụ ga-enwerịrị ọgwụgwọ dị mgbagwoju anya tupu usoro epitaxy amalite. Tupu itolite GaN epitaxy na mkpụrụ sapphire, a ga-ebu ụzọ ihicha ihe dị n'elu ala iji wepụ ihe mmetọ, mmebi ihe nchacha mma, wdg, na imepụta usoro na nhazi elu. Mgbe ahụ, a na-eme ka nitrided n'elu ala ahụ ka ọ gbanwee njirimara wetting nke oyi akwa epitaxial. N'ikpeazụ, ọ dị mkpa ka etinye akwa akwa akwa AlN dị mkpa (na-abụkarị 10-100nm) n'elu mkpụrụ osisi ma kpochie ya na obere okpomọkụ iji kwadebe maka uto epitaxial ikpeazụ. N'agbanyeghị nke ahụ, njupụta nhụsianya dị na ihe nkiri GaN epitaxial nke toro na sapphire substrates ka dị elu karịa nke ihe nkiri homoepitaxial (ihe dị ka 1010cm-2, ma e jiri ya tụnyere ihe nhụsianya efu efu na ihe nkiri silicon homoepitaxial ma ọ bụ gallium arsenide homoepitaxial films, ma ọ bụ n'etiti 1010 cm). 2). Njupụta ntụpọ dị elu na-ebelata mbugharị ụgbọ ala, si otú ahụ na-ebelata ndị na-ebu obere oge ndụ yana ibelata conductivity thermal, nke niile ga-ebelata arụmọrụ ngwaọrụ [4];
✔ Ọnụ ọgụgụ mgbasawanye okpomọkụ nke sapphire dị ukwuu karịa nke GaN, ya mere a ga-emepụta nrụgide nrụgide biaxial na epitaxial oyi akwa n'oge usoro nke jụrụ oyi site na ntinye okpomọkụ na okpomọkụ. Maka ihe nkiri epitaxial buru ibu, nrụgide a nwere ike ime ka mgbawa nke ihe nkiri ahụ ma ọ bụ ọbụna mkpụrụ;
✔ E jiri ya tụnyere ndị ọzọ substrates, thermal conductivity nke sapphire substrates dị ala (ihe dị ka 0.25W * cm-1 * K-1 na 100 ℃), na okpomọkụ dissipation arụmọrụ adịghị mma;
✔ N'ihi na-adịghị mma conductivity, sapphire substrates adịghị akwado ha mwekota na ngwa na ndị ọzọ semiconductor ngwaọrụ.
Ọ bụ ezie na njupụta ntụpọ nke GaN epitaxial layers toro na sapphire dị elu, ọ dịghị ka ọ na-ebelata arụmọrụ optoelectronic nke LEDs na-acha anụnụ anụnụ na-acha anụnụ anụnụ nke GaN, ya mere a ka na-ejikarị substrates sapphire eme ihe maka LEDs dabeere na GaN.
Site na mmepe nke ngwa ọhụrụ nke ngwaọrụ GaN dị ka lasers ma ọ bụ ngwaọrụ ndị ọzọ nwere ike dị elu, ntụpọ dị n'ime ala nke sapphire substrates aghọwo ihe mgbochi na ngwa ha. Na mgbakwunye, site na mmepe nke teknụzụ uto nke mkpụrụ osisi SiC, mbelata ọnụ ahịa yana ntozu nke teknụzụ GaN epitaxial na mkpụrụ Si, nyocha ndị ọzọ gbasara ọkwa GaN epitaxial na-eto eto na mkpụrụ sapphire ejirila nwayọọ nwayọọ gosipụta omume jụrụ oyi.
GaN epitaxy na SiC
E jiri ya tụnyere sapphire, ihe ndị SiC (4H- na 6H-crystals) nwere obere lattice na-adaba na ọkwa GaN epitaxial layers (3.1%, nke kwekọrọ na [0001] ihe nkiri epitaxial na-adabere na ya), ntụgharị ọkụ dị elu (ihe dịka 3.8W * cm-1 * K). -1), wdg Na mgbakwunye, conductivity nke SiC substrates na-enye ohere eletriki kọntaktị a ga-eme na azụ nke mkpụrụ, nke na-enyere aka mee ka usoro ngwaọrụ dị mfe. Ịdị adị nke uru ndị a adọtala ndị na-eme nchọpụta ka ha rụọ ọrụ na GaN epitaxy na silicon carbide substrates.
Agbanyeghị, ịrụ ọrụ ozugbo na mkpụrụ SiC iji zere ịrị elu GaN na-eto eto na-echekwa ọtụtụ ọghọm dị iche iche, gụnyere ndị a:
✔ Ọdịdị elu nke ihe ndị dị na SiC dị elu karịa nke sapphire substrates (sapphire roughness 0.1nm RMS, SiC roughness 1nm RMS), SiC substrates nwere ike siri ike na arụ ọrụ nhazi adịghị mma, na nke a siri ike na mmebi polishing bụ otu n'ime ihe ndị ahụ. isi mmalite nke ntụpọ na GaN epilayers.
✔ Ihe nkedo nke screw dislocation nke SiC substrates dị elu (dislocation density 103-104cm-2), screw dislocations nwere ike gbasaa na GaN epilayer ma belata arụmọrụ ngwaọrụ;
✔ Nhazi atọm n'elu ala na-eme ka e nwee mmejọ nke stacking (BSFs) na GaN epilayer. Maka epitaxial GaN na mkpụrụ SiC, enwere ọtụtụ iwu nhazi atomic nwere ike ime na mkpụrụ osisi ahụ, na-ebute usoro mbido atọm mbụ nke epitaxial GaN oyi akwa na ya, nke na-adịkarị mfe ikpokọta mmejọ. Mmebi nke stacking (SFs) na-ewebata oghere eletrik arụnyere n'akụkụ c-axis, na-eduga na nsogbu dị ka ntapu nke ngwaọrụ nkewa ụgbọ elu;
✔ Ọnụ ọgụgụ mgbasawanye thermal nke mkpụrụ osisi SiC pere mpe karịa nke AlN na GaN, nke na-ebute oke nrụgide thermal n'etiti akwa epitaxial na mkpụrụ n'oge usoro jụrụ oyi. Waltereit na Brand buru amụma dabere na nsonaazụ nyocha ha na enwere ike ibelata ma ọ bụ dozie nsogbu a site n'ịzụlite GaN epitaxial layers na steepụ nucleation nke dị gịrịgịrị, na-ejikọta ọnụ;
✔ Nsogbu nke ogbenye wettability nke Ga atọm. Mgbe ọ na-eto eto GaN epitaxial layers ozugbo n'elu SiC, n'ihi enweghị mmiri mmiri dị n'etiti atọm abụọ ahụ, GaN na-enwekarị uto agwaetiti 3D n'elu ala. Iwebata oyi akwa mkpuchi bụ ihe a na-ejikarị eme ihe iji melite ogo ihe epitaxial na GaN epitaxy. Ewebata akwa akwa akwa AlN ma ọ bụ AlxGa1-xN nwere ike melite wettability nke elu SiC nke ọma wee mee ka akwa GaN epitaxial tolite na akụkụ abụọ. Na mgbakwunye, ọ nwekwara ike ịhazi nrụgide ma gbochie mmebi mkpụrụ site na ịgbatị GaN epitaxy;
✔ Teknụzụ nkwadebe nke mkpụrụ osisi SiC etobeghị, ọnụ ahịa mkpụrụ dị elu, enwere ndị na-ebubata ya na obere ọkọnọ.
Nnyocha nke Torres et al na-egosi na itinye mkpụrụ osisi SiC na H2 na okpomọkụ dị elu (1600 Celsius C) tupu epitaxy nwere ike ịmepụta usoro nhazi usoro n'elu ala, si otú ahụ nweta ihe nkiri AlN epitaxial dị elu karịa mgbe ọ bụ kpọmkwem. toro na mbụ mkpụrụ n'elu. Nnyocha nke Xie na ndị otu ya na-egosikwa na etching pretreatment nke silicon carbide mkpụrụ nwere ike imeziwanye ọdịdị ọdịdị elu na kristal nke GaN epitaxial Layer. Smith et al. chọpụtara na ndọpụ eriri nke sitere na mkpụrụ / ihe nchekwa oyi akwa na ebe nchekwa oyi akwa / epitaxial Layer interfaces metụtara mkpọda nke mkpụrụ osisi [5].
Ọgụgụ 4 TEM morphology nke GaN epitaxial oyi akwa sample toro na 6H-SiC mkpụrụ (0001) n'okpuru dị iche iche n'elu ọgwụgwọ ọnọdụ (a) chemical ihicha; (b) ihicha kemịkalụ + ọgwụgwọ plasma hydrogen; (c) ihicha kemịkalụ + ọgwụgwọ plasma hydrogen + 1300 ℃ ọgwụgwọ okpomọkụ hydrogen maka 30min
GaN epitaxy na Si
E jiri ya tụnyere silicon carbide, sapphire na ihe ndị ọzọ, usoro nkwadebe mkpụrụ silịkọn tozuru oke, ọ nwekwara ike inye mkpụrụ osisi buru ibu buru ibu na arụmọrụ dị elu. N'otu oge ahụ, ọkụ ọkụ na ọkụ eletrik dị mma, na usoro ngwaọrụ eletrọnịkị Si tozuru oke. Ohere nke ijikọ ngwa optoelectronic GaN nke ọma na ngwaọrụ eletrọnịkị Si n'ọdịniihu na-emekwa ka uto nke GaN epitaxy na silicon mara mma nke ukwuu.
Otú ọ dị, n'ihi nnukwu ọdịiche dị na lattice constants n'etiti Si substrate na GaN ihe, heterogeneous epitaxy nke GaN on Si mkpụrụ bụ ihe a na-ahụkarị nnukwu mismatch epitaxy, na ọ dịkwa mkpa iche ihu ọtụtụ nsogbu:
✔ Nsogbu ike ihu ihu ihu. Mgbe GaN tolitere na mkpụrụ Si, a ga-ebu ụzọ mee nitrided elu nke mkpụrụ mkpụrụ Si ka ọ bụrụ oyi akwa silicon nitride amorphous nke na-adịghị akwado nucleation na uto nke GaN dị elu. Na mgbakwunye, elu Si ga-ebu ụzọ kpọtụrụ Ga, nke ga-emebi elu nke mkpụrụ Si. N'ebe okpomọkụ dị elu, nbibi nke elu Si ga-agbasa n'ime akwa epitaxial GaN iji mepụta ntụpọ silicon ojii.
✔ Nkwekọrịta na-agbanwe agbanwe mgbe niile n'etiti GaN na Si dị ukwuu (~ 17%), nke ga-eduga n'ịmepụta ihe mgbagwoju anya dị elu ma na-ebelata àgwà nke oyi akwa epitaxial;
✔ E jiri ya tụnyere Si, GaN nwere ọnụọgụ mgbasawanye ọkụ ka ukwuu (Ntụpọ mgbasawanye nke GaN bụ ihe dịka 5.6 × 10-6K-1, Si's thermal expansion coefficient of 2.6 × 10-6K-1), na enwere ike ịmepụta mgbape na GaN. oyi akwa epitaxial n'oge oyi nke epitaxial okpomọkụ ruo ụlọ okpomọkụ;
✔ Si na-emeghachi omume na NH3 na oke okpomọkụ iji mepụta polycrystalline SiNx. AlN enweghị ike ịmepụta oghere gbadoro ụkwụ na nke ọma na polycrystalline SiNx, nke na-eduga na ntuzi aka na-adịghị mma nke oyi akwa GaN mechara tolite na ọtụtụ ntụpọ, na-ebute ogo kristal na-adịghị mma nke akwa GaN epitaxial, yana ọ na-esiri ike ịmepụta otu-crystalline. GaN epitaxial oyi akwa [6].
Iji dozie nsogbu nke nnukwu lattice mismatch, ndị nchọpụta agbalịwo iwebata ihe ndị dị ka AlAs, GaAs, AlN, GaN, ZnO, na SiC dị ka ihe nchekwa ihe na Si substrates. Iji zere nhazi nke polycrystalline SiNx ma belata mmetụta ọjọọ ya na àgwà kristal nke GaN / AlN / Si (111), a na-achọkarị TMAl ka ewebata ya ruo oge ụfọdụ tupu ọganihu epitaxial nke AlN buffer Layer. iji gbochie NH3 imeghachi omume na elu Si ekpughere iji mepụta SiNx. Tụkwasị na nke a, enwere ike iji teknụzụ epitaxial dị ka nkà na ụzụ substrate emepụtara ka ọ dịkwuo mma nke oyi akwa epitaxial. Mmepe nke teknụzụ ndị a na-enyere aka igbochi nhazi nke SiNx na interface epitaxial, na-akwalite uto akụkụ abụọ nke oyi akwa GaN epitaxial, ma melite ogo ogo nke oyi akwa epitaxial. Na mgbakwunye, a na-ewebata oyi akwa mkpuchi AlN iji kwụọ ụgwọ maka nrụgide tensile nke kpatara ọdịiche dị na ọnụọgụ mgbasawanye ọkụ iji zere mgbawa na akwa GaN epitaxial oyi akwa na mkpụrụ silicon. Nnyocha nke Krost na-egosi na enwere njikọ dị mma n'etiti ọkpụrụkpụ nke oyi akwa AlN na mbelata nsogbu. Mgbe ọkpụrụkpụ oyi akwa ahụ ruru 12nm, akwa epitaxial toro karịa 6μm nwere ike itolite na mkpụrụ silicon site na atụmatụ uto kwesịrị ekwesị na-enweghị mgbawa epitaxial.
Mgbe ogologo oge gbalịsiri ike site n'aka ndị nchọpụta, àgwà nke GaN epitaxial layers toro na silicon substrates enwewo ọganihu dị ukwuu, na ngwaọrụ ndị dị ka transistor mmetụta ubi, Schottky barrier ultraviolet detectors, blue-green LEDs na ultraviolet lasers enweela ọganihu dị ukwuu.
Na nchịkọta, ebe ọ bụ na GaN epitaxial substrates ndị a na-ejikarị bụ epitaxy dị iche iche, ha niile na-eche nsogbu ndị a na-enwekarị ihu dị ka nkwụsị nke lattice na nnukwu ọdịiche dị na ọnụọgụ mgbasawanye okpomọkụ ruo ogo dịgasị iche iche. Mgbochi epitaxial GaN na-emekọ ihe na-ejedebe site na ntozu nke teknụzụ, na emepụtabeghị mkpụrụ ndị ahụ n'ọtụtụ ebe. Ọnụ ahịa mmepụta ihe dị elu, nha mkpụrụ dị ntakịrị, na àgwà nke mkpụrụ osisi adịghị mma. Mmepe nke ọhụrụ GaN epitaxial substrates na mma nke epitaxial àgwà ka bụ otu n'ime ihe ndị dị mkpa na-egbochi ọganihu ọzọ nke ụlọ ọrụ GaN epitaxial.
IV. Ụzọ ndị a na-ahụkarị maka GaN epitaxy
MOCVD (mkpokọta vapor kemịkalụ)
Ọ dị ka epitaxy na-arụkọ ọrụ ọnụ na mkpụrụ GaN bụ nhọrọ kacha mma maka Epitaxy GaN. Otú ọ dị, ebe ọ bụ na precursors nke kemịkal vepor deposition bụ trimethylgallium na amonia, na ebu gas bụ hydrogen, ahụkarị MOCVD uto okpomọkụ bụ banyere 1000-1100 ℃, na uto nke MOCVD bụ banyere a ole na ole microns kwa awa. Ọ nwere ike imepụta oghere dị elu na ọkwa atọm, nke dabara adaba maka mmepe heterojunctions, olulu mmiri quantum, superlatices na ihe ndị ọzọ. Ọganihu ngwa ngwa ya, ịdị n'otu dị mma, na dabara adaba maka nnukwu mpaghara na uto dị iche iche na-ejikarị eme ihe na mmepụta ụlọ ọrụ.
MBE (molecular beam epitaxy)
Na molecular beam epitaxy, Ga na-eji isi mmalite, na nitrogen na-arụ ọrụ na-enweta site na nitrogen site na plasma RF. E jiri ya tụnyere usoro MOCVD, okpomọkụ nke MBE dị ihe dịka 350-400 ℃ dị ala. Okpomọkụ na-eto eto dị ala nwere ike zere mmetọ ụfọdụ nke nwere ike bute ya site na oke okpomọkụ gburugburu. Sistemụ MBE na-arụ ọrụ n'okpuru oghere dị oke elu, nke na-enye ya ohere ijikọ ọtụtụ ụzọ nchọpụta n'ime ọnọdụ. N'otu oge ahụ, a pụghị iji ọnụ ọgụgụ ya na mmepụta ya tụnyere MOCVD, a na-ejikwa ya na nchọpụta sayensị [7].
Ọgụgụ 5 (a) Eiko-MBE schematic (b) MBE isi mmeghachi omume chamber schematic
Usoro HVPE (hydride vapor phase epitaxy)
Ihe mmalite nke usoro epitaxy hydride vapor phase bụ GaCl3 na NH3. Detchprohm et al. jiri usoro a tolite akwa GaN epitaxial ọtụtụ narị microns n'elu ala sapphire. N'ime nnwale ha, a na-akụ oyi akwa nke ZnO n'etiti mkpụrụ sapphire na oyi akwa epitaxial dị ka oyi akwa mkpuchi, na oyi akwa epitaxial na-esi n'elu ala dị elu. E jiri ya tụnyere MOCVD na MBE, akụkụ bụ isi nke usoro HVPE bụ ọnụ ọgụgụ ya dị elu, nke kwesịrị ekwesị maka ịmepụta akwa akwa na nnukwu ihe. Otú ọ dị, mgbe ọkpụrụkpụ nke epitaxial oyi akwa karịrị 20μm, epitaxial oyi akwa nke usoro a na-emepụta na-adịkarị mfe mgbawa.
Akira USUI webatara teknụzụ substrate nwere ụkpụrụ dabere na usoro a. Ha buru ụzọ too akwa GaN epitaxial gbara ọkpụrụkpụ 1-1.5μm n'elu mkpụrụ sapphire site na iji usoro MOCVD. Ihe oyi akwa epitaxial nwere akwa nchekwa nchekwa GaN 20nm toro n'okpuru ọnọdụ okpomọkụ dị ala yana akwa GaN toro n'okpuru ọnọdụ okpomọkụ dị elu. Mgbe ahụ, na 430 ℃, a oyi akwa nke SiO2 e plated n'elu nke epitaxial oyi akwa, na a na-eme n'ọnyá windo na SiO2 film site photolithography. Oghere eriri ahụ bụ 7μm na obosara nkpuchi ahụ sitere na 1μm ruo 4μm. Ka emechara nkwalite a, ha nwetara akwa GaN epitaxial na mkpụrụ sapphire dayameta 2-inch nke enweghị mgbawa yana dịkwa nro dị ka enyo ọbụlagodi mgbe oke ahụ ruru iri iri ma ọ bụ ọbụna narị microns. E belatara njupụta ntụpọ site na 109-1010cm-2 nke usoro HVPE ọdịnala ruo ihe dịka 6 × 107cm-2. Ha rụkwara aka na nnwale ahụ na mgbe ọ̀tụ̀tụ̀ uto gafere 75μm/h, ihe nlele ahụ ga-adị njọ[8].
Onyonyo 6 Ihe eserese eserese
V. Nchịkọta na Outlook
Ngwa GaN malitere ịpụta na 2014 mgbe ọkụ ọkụ na-acha anụnụ anụnụ meriri Nobel Prize na Physics n'afọ ahụ, wee banye n'ọhịa nke ngwa ngwa ngwa ngwa ngwa ngwa n'ahịa ndị ahịa. N'ezie, ngwa ndị dị na amplifiers ike na ngwaọrụ RF ejiri na ọdụ ọdụ 5G nke ọtụtụ mmadụ na-ahụghị ewepụtala nwayọ. N'ime afọ ndị na-adịbeghị anya, a na-atụ anya na ọ ga-emepe ihe uto ọhụrụ maka ahịa ngwa ngwa GaN dabere na GaN.
Nnukwu ọchịchọ ahịa ga-akwalite mmepe nke ụlọ ọrụ na teknụzụ metụtara GaN. Site na ntozu oke na nkwalite nke ụlọ ọrụ mmepụta ihe metụtara GaN, nsogbu ndị dị ugbu a na teknụzụ GaN epitaxial ga-emecha meziwanye ma ọ bụ merie. N'ọdịnihu, ndị mmadụ ga-emepewanye teknụzụ epitaxial ọhụrụ yana nhọrọ mkpụrụ osisi mara mma. Ka ọ na-erule mgbe ahụ, ndị mmadụ ga-enwe ike ịhọrọ teknụzụ nyocha mpụga kacha dabara adaba na mkpụrụ maka ọnọdụ ngwa dị iche iche dabere na njirimara nke ọnọdụ ngwa ahụ, wee mepụta ngwaahịa ahaziri ahazi kachasị asọmpi.
Oge nzipu: Jun-28-2024