Mfundo ya bwato la graphite la PECVD la ma solar cell (chophimba) | VET Energy

Choyamba, tiyenera kudziwaPECVD(Plasma Enhanced Chemical Npor Deposition). Plasma ndi kuwonjezereka kwa kayendedwe ka kutentha kwa mamolekyulu azinthu. Kugundana pakati pawo kudzapangitsa kuti mamolekyu a mpweya asinthidwe kukhala ayoni, ndipo zinthuzo zidzakhala chisakanizo cha ma ayoni abwino oyenda momasuka, ma elekitironi ndi tinthu tating'onoting'ono tomwe timalumikizana.

 

Akuti kuchuluka kwa kuwala komwe kumatayika pa silicon pamwamba ndi pafupifupi 35%. Filimu yotsutsana ndi kuwala imatha kusintha kwambiri kuchuluka kwa kuwala kwa dzuwa komwe kumagwiritsiridwa ntchito ndi selo ya batri, zomwe zimathandiza kuwonjezera kuchuluka kwa mphamvu yopangidwa ndi photogenerated current motero kupititsa patsogolo mphamvu yosinthira. Nthawi yomweyo, haidrojeni yomwe ili mufilimuyi imadutsa pamwamba pa selo ya batri, imachepetsa kuchuluka kwa recombination pamwamba pa emitter junction, imachepetsa mphamvu yakuda, imawonjezera voliyumu yotseguka, komanso imawonjezera mphamvu yosinthira photoelectric. Kuthira kwa kutentha kwachangu komwe kumachitika nthawi yomweyo mu njira yoyaka moto kumaswa ma bond ena a Si-H ndi NH, ndipo H yomasulidwayo imalimbitsanso mphamvu yosinthira batri.

 

Popeza zinthu za silicon zomwe zimakhala ndi photovoltaic zimakhala ndi zinthu zambiri zosafunika komanso zolakwika, nthawi yogwira ntchito ya silicon komanso nthawi yofalikira imachepa, zomwe zimapangitsa kuti batire isamagwire bwino ntchito. H imatha kuchitapo kanthu ndi zinthu zosafunika kapena zosafunika mu silicon, motero imasamutsa mphamvu mu bandgap kupita ku valence band kapena conduction band.

 

1. Mfundo ya PECVD

Dongosolo la PECVD ndi mndandanda wa majenereta omwe amagwiritsa ntchitoBoti la graphite la PECVD ndi ma exciters a plasma okwera kwambiri. Jenereta ya plasma imayikidwa mwachindunji pakati pa mbale yophimba kuti igwire ntchito pansi pa kupsinjika kochepa komanso kutentha kwakukulu. Mpweya wogwira ntchito womwe umagwiritsidwa ntchito ndi silane SiH4 ndi ammonia NH3. Mpweya uwu umagwira ntchito pa silicon nitride yomwe imasungidwa pa silicon wafer. Zizindikiro zosiyanasiyana zoyatsira zitha kupezeka posintha chiŵerengero cha silane ndi ammonia. Panthawi yoyika, maatomu ambiri a haidrojeni ndi ma ayoni a haidrojeni amapangidwa, zomwe zimapangitsa kuti hydrogen passivation ya wafer ikhale yabwino kwambiri. Mu vacuum ndi kutentha kozungulira kwa madigiri 480 Celsius, wosanjikiza wa SixNy umakutidwa pamwamba pa silicon wafer poyendetsaBoti la graphite la PECVD.

 

3SiH4+4NH3 → Si3N4+12H2

 

2. Si3N4

Mtundu wa filimu ya Si3N4 umasintha ndi makulidwe ake. Kawirikawiri, makulidwe oyenera amakhala pakati pa 75 ndi 80 nm, omwe amawoneka ngati buluu wakuda. Chizindikiro chowongolera cha filimu ya Si3N4 chimakhala pakati pa 2.0 ndi 2.5. Mowa nthawi zambiri umagwiritsidwa ntchito poyesa chizindikiro chake chowongolera.

Mphamvu yabwino kwambiri yosinthira mawonekedwe a pamwamba, magwiridwe antchito abwino oletsa kuwunikira (kufananiza makulidwe a refractive index), njira yotsika kutentha (kuchepetsa ndalama moyenera), ndi ma H ion opangidwa amasinthasintha mawonekedwe a silicon wafer.

 

3. Nkhani zomwe zimachitika kawirikawiri pa malo ochitira kupaka utoto

Kukhuthala kwa filimu: 

Nthawi yoyika filimuyi ndi yosiyana pa makulidwe osiyanasiyana. Nthawi yoyika iyenera kuwonjezeredwa kapena kuchepetsedwa moyenerera malinga ndi mtundu wa chophimbacho. Ngati filimuyo ndi yoyera, nthawi yoyika iyenera kuchepetsedwa. Ngati ndi yofiira, iyenera kuwonjezeredwa moyenerera. Boti lililonse la mafilimu liyenera kutsimikiziridwa mokwanira, ndipo zinthu zolakwika siziloledwa kuyenda mu njira yotsatira. Mwachitsanzo, ngati chophimbacho chili chofooka, monga mawanga amitundu ndi zizindikiro zamadzi, kuyera kofala kwambiri pamwamba, kusiyana kwa mitundu, ndi mawanga oyera pamzere wopanga ziyenera kusankhidwa pakapita nthawi. Kuyera pamwamba kumachitika makamaka chifukwa cha filimu yokhuthala ya silicon nitride, yomwe ingasinthidwe posintha nthawi yoyika filimuyi; filimu yosiyana mitundu makamaka imayambitsidwa ndi kutsekeka kwa njira ya mpweya, kutuluka kwa chubu cha quartz, kulephera kwa microwave, ndi zina zotero; mawanga oyera makamaka amayamba chifukwa cha mawanga akuda ang'onoang'ono mu njira yapitayi. Kuyang'anira kuwunikira, index ya refractive, ndi zina zotero, chitetezo cha mpweya wapadera, ndi zina zotero.

 

Madontho oyera pamwamba:

PECVD ndi njira yofunika kwambiri m'maselo a dzuwa ndipo ndi chizindikiro chofunikira cha momwe maselo a dzuwa a kampani amagwirira ntchito. Njira ya PECVD nthawi zambiri imakhala yotanganidwa, ndipo gulu lililonse la maselo liyenera kuyang'aniridwa. Pali machubu ambiri ophimba ng'anjo, ndipo chubu chilichonse nthawi zambiri chimakhala ndi maselo mazana ambiri (kutengera zida). Pambuyo posintha magawo a njira, nthawi yotsimikizira imakhala yayitali. Ukadaulo wophimba ndi ukadaulo womwe makampani onse a photovoltaic amauona kukhala wofunika kwambiri. Kugwira ntchito bwino kwa maselo a dzuwa kumatha kukonzedwa mwa kukonza ukadaulo wophimba. M'tsogolomu, ukadaulo wa pamwamba pa maselo a dzuwa ukhoza kukhala chitukuko pakugwira ntchito bwino kwa maselo a dzuwa.