Imigaqo yobuGcisa kunye neeNkqubo ze-LED Epitaxial Wafers

Ukususela kumgaqo wokusebenza wee-LED, kuyacaca ukuba i-epitaxial wafer material iyona nxalenye ephambili ye-LED. Ngapha koko, iiparamitha eziphambili ze-optoelectronic ezinje ngewavelength, ukukhanya, kunye nombane ohamba phambili zimiselwa ubukhulu becala zizinto ze-epitaxial. Itekhnoloji ye-Epitaxial wafer kunye nezixhobo zibaluleke kakhulu kwinkqubo yokwenziwa kwemveliso, kunye ne-Metal-Organic Chemical Vapor Deposition (MOCVD) ibe yeyona ndlela iphambili yokukhulisa i-single-crystal layers ye-III-V, iikhompawundi ze-II-VI, kunye ne-alloys yazo. Apha ngezantsi kukho iindlela ezizayo kwitekhnoloji ye-LED epitaxial wafer.

1. Uphuculo lweNkqubo yoHlumo enaManyathelo amabini

Okwangoku, ukuveliswa kwezorhwebo kusebenzisa inkqubo yokukhula kwamanyathelo amabini, kodwa inani le-substrates elinokulayishwa ngokukhawuleza lilinganiselwe. Ngelixa iinkqubo ze-6-wafer zivuthiwe, oomatshini abaphatha ii-wafers ezijikelezayo ezingama-20 basaphantsi kophuhliso. Ukwandisa inani lee-wafers kudla ngokukhokelela ekungafaneni okufanayo kwiileya ze-epitaxial. Uphuhliso lwexesha elizayo luya kugxila kumacala amabini:

• Ukuphuhlisa itekhnoloji evumela ukulayisha ii-substrates ezininzi kwigumbi elilodwa lokusabela, okwenza ukuba zifaneleke ngakumbi kwimveliso emikhulu kunye nokunciphisa iindleko.
• Ukuqhubela phambili ngezixhobo ezizenzekelayo, eziphindaphindwayo ze-wafer enye.

2. I-Hydride Vapor Phase Epitaxy (HVPE) Technology

Obu buchwephesha buvumela ukukhula okukhawulezayo kweefilimu ezishinyeneyo ezinoxinano oluphantsi lwe-dislocation, ezinokusebenza njenge-substrates yokukhula kwe-homoepitaxial kusetyenziswa ezinye iindlela. Ukongeza, iifilimu ze-GaN ezahlulwe kwi-substrate zinokuba zezinye iitshiphusi ezininzi ze-GaN zekristale enye. Nangona kunjalo, i-HVPE inezithintelo, ezinjengobunzima kulawulo oluchanekileyo kunye neegesi eziphazamisayo ezithintela ukuphucuka ngakumbi kucoceko lwe-GaN.

I-Si-doped HVPE-GaN

(a) Ubume be-Si-doped HVPE-GaN reactor; (b) Umfanekiso we-800 μm- ubukhulu be-Si-doped HVPE-GaN;

(c) Ukusasazwa koxinaniso lomthwali wasimahla ecaleni kobubanzi be-Si-doped HVPE-GaN

3. I-Selective Epitaxial Growth okanye i-Lateral Epitaxial Growth Technology

Obu buchule bunokunciphisa ngakumbi ukuxinana kwe-dislocation kunye nokuphucula umgangatho wekristale ye-GaN epitaxial layers. Inkqubo ibandakanya:

• Ukubeka i-GaN layer kwi-substrate efanelekileyo (isafire okanye i-SiC).
• Ukubeka umaleko we-polycrystalline SiO₂ imaski ngaphezulu.
• Ukusebenzisa i-photolithography kunye ne-etching ukwenza iifestile ze-GaN kunye nemicu ye-mask ye-SiO₂.Ngexesha lokukhula okulandelayo, i-GaN iqala ukukhula ngokuthe nkqo kwiifestile kwaye emva koko ingaphaya kwemicu yeSiO₂.

XKH's GaN-on-Sapphire wafer

4. IPendeo-Epitaxy Technology

Le ndlela inciphisa kakhulu iziphene ze-lattice ezibangelwa yi-lattice kunye ne-thermal dismatch phakathi kwe-substrate kunye ne-epitaxial layer, iphucula ngakumbi umgangatho we-crystal ye-GaN. Amanyathelo aquka:

• Ukukhulisa i-GaN epitaxial layer kwi-substrate efanelekileyo (6H-SiC okanye i-Si) usebenzisa inkqubo yamanyathelo amabini.
• Ukwenza i-etching ekhethiweyo ye-epitaxial layer ukuya kwi-substrate, ukudala intsika eguqukayo (i-GaN / buffer / substrate) kunye nezakhiwo zomsele.
• Ukukhulisa iileya ze-GaN ezongezelelweyo, ezithi zinwenwe ngokuthe ngcembe ukusuka kumacaleni eentsika ze-GaN zoqobo, zixhonywe phezu kwemisele.Kuba akukho maski isetyenziswayo, oku kuthintela unxibelelwano phakathi kwe-GaN kunye nezixhobo zemaski.

XKH's GaN-on-Silicon wafer

5. Ukuphuhliswa koMfutshane-wavelength UV LED Epitaxial Materials

Oku kubeka isiseko esiluqilima se-UV-imincili ye-phosphor-based LEDs ezimhlophe. Iiphosphors ezininzi ezisebenza kakuhle kakhulu zinokuvuyiswa kukukhanya kwe-UV, zinika ukusebenza okuphezulu kokukhanya kuneyag: inkqubo yeCe, ngaloo ndlela iqhubela phambili ukusebenza kwe-LED emhlophe.

6. Multi-Quantum Well (MQW) Chip Technology

Kwizakhiwo ze-MQW, ukungcola okwahlukeneyo kwenziwa ngexesha lokukhula komgangatho okhupha ukukhanya ukudala amaqula e-quantum ahlukeneyo. Ukudityaniswa kwakhona kweefotoni eziphuma kula maqula kuvelisa ukukhanya okumhlophe ngokuthe ngqo. Le ndlela iphucula ukusebenza kakuhle okukhanyayo, inciphisa iindleko, kwaye yenza lula ukupakishwa kunye nolawulo lwesekethe, nangona inika imingeni enkulu yobugcisa.

7. Uphuhliso lweTekhnoloji ye "Photon Recycling".

NgoJanuwari 1999, iSumitomo yaseJapan yavelisa i-LED emhlophe isebenzisa imathiriyeli yeZnSe. Itekhnoloji ibandakanya ukukhulisa ifilimu encinci ye-CdZnSe kwi-ZnSe enye-crystal substrate. Xa ifakwe umbane, ifilimu ikhupha ukukhanya okuluhlaza okwesibhakabhaka, okusebenzisana ne-ZnSe substrate ukuvelisa ukukhanya okutyheli okuhambelanayo, okukhokelela kukukhanya okumhlophe. Ngokufanayo, iZiko loPhando ngeFotonics yeYunivesithi yaseBoston yafaka i-AlInGaP semiconductor ikhompawundi kwi-blue GaN-LED ukuvelisa ukukhanya okumhlophe.

8. I-LED Epitaxial Wafer Process Flow

① I-Epitaxial Wafer Fabrication:
Inkqutyana → Uyilo lolwakhiwo → Ukukhula umaleko wesithinteli → N-uhlobo lwe-GaN yokukhula umaleko → I-MQW ekhupha umaleko wokukhula → Ukukhula komaleko we-P-uhlobo lwe-GaN → I-Anealing → Uvavanyo (i-photoluminescence, i-X-reyi) → i-Epitaxial wafer

② Ukwenziwa kweChip:
I-Epitaxial wafer → uyilo lwemaski kunye nokuyila → Ifotolithography → i-ion etching → i-electrode yodidi lwe-N (i-electrode, i-annealing, i-etching) → i-electrode yodidi lwe-P (i-electrode, i-annealing, i-etching) → I-Dicing → Ukuhlolwa kwe-chip kunye nokuhlelwa.

I-wafer ye-ZMSH ye-GaN-on-SiC