Gabatarwa ga TOPCon Solar Cells

TOPCon (Tunnel Oxide Passivating Contact) fasaha ce ta N-type wafer cell wacce ta fara bayyana a shekarar 2013. TOPCon solar cell wani nau'in tunnel oxide passivated contact solar cell ne da aka gina akan N-type substrate.

Idan aka kwatanta da PERC cells, TOPcon cells suna amfani da tunnel oxide layer with excellent charge transport properties a matsayin Layer na jigilar caji a bayan tantanin halitta. A saman wannan, an saka fim ɗin polysilicon mai ɗauke da kusan 20nm don samar da tsarin tuntuɓar da aka rufe a gefen baya. Wannan yana rage haɗuwar saman da haɗuwar tuntuɓar ƙarfe, yana ɗaga ƙarfin buɗe kewayawa, kuma yana inganta ingancin canjin makamashi.

TOPCon fasahar hasken rana ce ta tuntuɓar oxide mai rufewa bisa ka'idar masu ɗaukar kaya, tana samar da ingantaccen tasirin rufewa.

Tantanin halitta na TOPCon yana amfani da N-type substrate. Ana shirya siririn oxide Layer a bayan tantanin halitta, sannan a saka fim ɗin da aka ɗora. Tare waɗannan biyu suna samar da tsarin tuntuɓar da aka rufe wanda yake rage haɗuwar saman da haɗuwar tuntuɓar ƙarfe, yana ba da damar ƙarin haɓaka ingancin canjin N-PERT tantanin halitta.

Fasahar TOPCon tana adanawa da sake amfani da kayan aiki da hanyoyin samar da sel P-type na al'ada da ake da su gwargwadon iyawa. Tana buƙatar ƙara kayan aikin watsawar boron da kayan aikin jigilar fim na bakin ciki kawai, ba tare da buƙatar buɗe ko daidaita gefen baya ba. Wannan yana sauƙaƙa tsarin samar da sel sosai kuma yana rage wahalar samar da yawa. Layin tsari yana da babban jituwa kuma yana iya aiki tare da layin samar da zafi mai zafi da ake amfani da shi don sel PERC da N-PERT bifacial.

Sel TOPCon suna da fa'idodin ƙarancin lalacewa, babban bifaciality, da ƙarancin ma'aunin zafin jiki, suna ba da fa'idar samar da wutar lantarki a matakin tashar wutar lantarki.

Matakan Ci gaban Sel TOPCon

Tarihin ci gaban sel TOPCon an raba shi zuwa matakai huɗu: lokacin samfurin fasaha, lokacin shirya samfur, lokacin tallata kasuwanci, da lokacin girma mai sauri.

Fa'idodin Sel TOPCon

Fa'idodin Aiki

• Babban ingancin juyawa. Godiya ga tsarin tuntuɓar da aka keɓance na sel TOPCon, iyakar ingancin ka'idar ya kai har 28.7%. Manyan masana'antun TOPCon sun riga sun sami ingancin samarwa sama da 25.5%, ingantawa sosai akan sel PERC na yau da kullun (ingancin juyawa na yanzu kusan 23.5%, iyakar ka'idar 24.5%).

• Babban bifaciality. Sel TOPCon bifacial suna samar da kusan 3% ƙarin wutar lantarki a kowace watt fiye da sel PERC bifacial. A cikin wannan yanayin tashar wutar lantarki ta ƙasa, wannan yana ba da ƙarin ribar samar da wutar lantarki.

• Ƙananan ma'aunin zafin jiki. Ma'aunin zafin jiki na nau'in N-type TOPCon modules yana da ƙasa da -0.30%/℃, mafi kyau fiye da -0.35%/℃ na nau'in P-type modules, yana nuna kwanciyar hankali a yanayin zafi mai girma.

• Ƙarancin lalacewa. Silicon crystalline N-type mai sinadarin Phosphorus yana ƙunshe da ƙarancin boron sosai, don haka babu sake haɗuwar boron-oxygen, yana ba shi fa'ida a cikin ƙimar lalacewa. Wasu modules na TOPCon suna nuna lalacewa na farkon shekara 1% da lalacewa na shekara-shekara na 0.4%, idan aka kwatanta da 2% na farkon shekara da 0.45% na PERC modules, yana kawo ribar samar da wutar lantarki a kowace watt a tsawon rayuwar module.

• Ƙarfin aiki mai ƙarfi a cikin ƙarancin haske. Cells na TOPCon suna amsa da kyau ga gajerun da dogayen raƙuman haske, suna kiyaye ƙarfin samar da wutar lantarki a ƙarƙashin yanayin ƙarancin haske kamar safiya, maraice, da yanayin gajimare.

Fa'idodin Tattalin Arziki

• Babban jituwa tare da masana'antar PERC, yana rage wahalar haɓaka fasaha. TOPCon na iya fadada daga fasahar tsari na PERC, yana buƙatar ƙarin matakai huɗu kawai: shirya boron emitter, girma Layer oxide na tunnel, ajiya da doping polysilicon, da tsaftacewa bayan diffusion. Wannan yana rage wahalar haɓakawa kuma yana hanzarta karɓar fasahar TOPCon.

• Canjin layi mai santsi tare da ƙarancin farashin saka hannun jari na kayan aiki. Gina sabon layin TOPCon yana buƙatar zuba jari na kayan aiki kusan miliyan 200-250, yayin da sabon layin HJT yana buƙatar miliyan 350-400. Saboda TOPCon yana da daidaiton kayan aiki mai kyau tare da layukan PERC da ke akwai, kawai ana buƙatar ƙara kayan aikin boron diffusion da polysilicon/amorphous silicon deposition (LPCVD / PECVD / PVD), tare da zuba jari na kayan aiki kusan miliyan 50-70. Wannan yana guje wa babban zuba jari a sabbin kayan aiki da manyan gyare-gyaren layi, yana mai da shi mai tattalin arziki sosai.

• Babban yuwuwar ƙarin farashi. Idan aka kwatanta da na'urorin PERC, na'urorin TOPCon suna ba da ƙarin wutar lantarki a kowace watt, ƙarin ribar samarwa, da ƙananan farashin tsarin, suna haifar da babban wuri don ƙarin farashi.

Tsarin Samar da Tantanin TOPCon

Idan aka kwatanta da tsarin monocrystalline PERC, tsarin samar da tantanin TOPCon yana ƙara matakai 2 zuwa 3: sanya tunnel oxide Layer (ultra-thin SiO2, 1-2nm), sanya intrinsic polysilicon passivation Layer (60-100nm), da phosphorus implantation.

Manyan Matakan Tsari da Ayyukansu

1. Tsaftacewa da Rubutu

Manufa: Bayan yanke wafer, gefuna sun lalace, tsarin crystal lattice ya karye, kuma sake haɗuwa da saman yana da tsanani. Tsaftacewa da rubutu galibi suna nufin cire lalacewar saman da kuma samar da tsarin kama haske mai siffar pyramid a saman. Hasken yana haskaka sau da yawa a saman wafer, yana rage haske.

2. Boron Diffusion

Manufa: Babban aikin shine samar da PN junction. Saboda boron yana da ƙarancin narkewa a cikin silicon, ana buƙatar yanayin zafi mai girma da lokaci mai tsawo don diffusion. Zaɓin tushen diffusion kuma yana shafar samarwa: chlorides suna da lalacewa, yayin da bromides suke da ɗanɗano, yana sa tsaftacewa ta zama mai wahala kuma yana ƙara farashin kulawa.

Boron diffusion yawanci ana kammala shi a yanayin zafi mafi girma - sama da 1000℃ - kuma idan aka kwatanta da zagayowar mintuna 102 da ake buƙata don phosphorus diffusion, zagayowar boron diffusion yana ɗaukar mintuna 150.

Ka'ida:

HCl da H2O na gas da ake samarwa ta hanyar halayen da ke cikin bututun tanderun ana ɗaukar su ta N2 kuma ana rarraba su daidai a cikin bututun. H2O kuma tana amsawa da BBr3 da O2 don samar da B2O3, wanda kuma yana amsawa don samar da HBO2 na gas; a yanayin zafi mai girma HBO2 yana rushewa zuwa B2O3, yana ba da damar B2O3 ya rarraba daidai a saman tantanin rana. Bugu da ƙari, H2O tana amsawa da B2O3 da aka ajiye a cikin bututun tanderun, yana hana tarin B2O3 a bangon bututun watsawa, yana tsawaita rayuwar kayan quartz, kuma yana ƙara tushen boron mai tasiri. HCl kuma na iya amsawa da ƙazantattun ƙarfe a saman tantanin rana da cikin bututun don samar da chlorides na ƙarfe na gas waɗanda ke fita tare da iskar gas, yana hana ƙazantattun ƙarfe shiga cikin tantanin rana yayin aikin zafi mai girma.

3. SE Laser Doping

Manufa: Don samar da selective emitter. Ana amfani da doping mai yawa a wuraren da ke kusa da wuraren tuntuɓar tsakanin gridlines na ƙarfe da wafer don rage juriyar tuntuɓar tsakanin lantarkin gaba na ƙarfe da wafer, yayin da doping mai ƙarancin yawa a waje da wuraren lantarki yana rage sake haɗuwa a cikin layin watsawa. Inganta emitter yana ƙara yawan fitarwa da ƙarfin lantarki na tantanin rana, don haka inganta ingancin canza wutar lantarki.

Inda laser ɗin yake a cikin kwararar TOPCon: PERC SE yana amfani da doping na phosphorus, yayin da TOPCon SE ke amfani da doping na boron. Saboda boron da phosphorus suna da ma'auni daban-daban na rarrabuwa, phosphorus yana watsawa cikin sauƙi daga silicon dioxide zuwa silicon, yayin da boron ke da wuya a tura shi kuma yana buƙatar ƙarin kuzari. Duk da haka, yawan kuzarin laser yana lalata wafer cikin sauƙi, yana sa doping na boron ya zama ƙalubale. Idan aka kwatanta da al'adar boron diffusion, ƙara fasahar SE a cikin sel TOPCon na iya inganta aiki da 0.5% a ka'ida, kuma a ainihin samarwa na iya samun karuwar aiki da 0.2-0.4%.

4. Etching

Manufa: Babban aikin etching shine cire BSG da junction na baya. Tsarin diffusion yana samar da yadudduka na diffusion a saman wafer da gefuna; yadudduka na diffusion na gefe yana haifar da gajeriyar kewayawa cikin sauƙi, kuma yadudduka na diffusion na saman yana shafar passivation na gaba, don haka dole ne a cire su duka. A halin yanzu, etching ana yin shi ne ta hanyoyin rigar, cire yadudduka na baya da gefe a cikin na'urori masu sarkar kafin a sarrafa gaban.

5. Shirya Layer na Tunnel Oxide da Layer na Polysilicon

Manufa: Ajiye Layer oxide tunnel mai 1-2nm a baya, sannan ajiye Layer polysilicon mai 60-100nm don samar da tsarin passivation. Akwai hanyoyi da yawa don shirya Layer passivation na TOPCon, musamman hanyoyin LPCVD, PECVD, da PVD. LPCVD shine babban abin da ake amfani da shi a yanzu, amma wrap-around deposition yana da tsanani, yayin da PECVD ke da karfin gaske a cikin aikin gaba daya.

6. Shirya Fim ɗin Anti-Reflection na Baya

Manufa: Shirya fim ɗin passivation anti-reflection a bayan tantanin halitta don ƙara ɗaukar haske. A lokaci guda, atom ɗin hydrogen da aka samar yayin aiwatar da fim ɗin SiNx suna passivate wafer.

7. Ajiye Aluminum Oxide na Gaba

Manufa: Ajiye Layer fim ɗin aluminum oxide a gaban wafer, wanda tare da wasu finai ke samar da tasirin passivation na gaba.

8. Shirya Fim ɗin Anti-Reflection na Gaba

Manufa: Fim ɗin anti-reflection na gaba yana aiki daidai da na baya. Bugu da ƙari, fim ɗin aluminum oxide da aka ajiye a gaba yana da sirara sosai kuma yana iya lalacewa cikin sauƙi yayin kera tantanin halitta da module na gaba, don haka SiNx na gaba yana kare aluminum oxide.

9. Buga Allon - Canja wurin Tsarin Laser

A halin yanzu, yawancin bugu na tantanin halitta har yanzu yana amfani da bugu na allo. A nan gaba, game da rage amfani da man azurfa ga tantanin halitta na N-type, Pattern Transfer Printing na iya samun fa'ida. Laser transfer sabuwar fasaha ce ta bugu mara lamba: ana shafa man da ake buƙata a kan wani takamaiman abu mai sassauƙa mai haske, kuma babban katako na Laser yana yin sikanin tsari mai sauri don canja wurin man daga abu mai sassauƙa mai haske zuwa saman tantanin halitta, yana samar da layukan grid da shirya na'urorin lantarki na gaba da baya.

10. Sintering

Ana samar da kyakkyawar hulɗar ohmic ta hanyar sintering mai zafi.

11. Rarraba ta atomatik

Ana rarraba tantanin halitta zuwa kwantena bisa ga bambancin ingancin su.

Hanyoyin Ci gaban TOPCon Cells a Nan gaba

A cikin 2023, matsakaicin ingancin juyar da tantanin halitta na N-type TOPCon ya kai 25.0%, kuma matsakaicin ingancin juyar da tantanin halitta na heterojunction ya kai 25.2%, duka sun nuna ci gaba mai mahimmanci akan 2022.

A cikin 2023, sabbin layukan samar da yawa da aka fara aiki sune layukan tantanin halitta na N-type. Yayin da ƙarfin tantanin halitta na N-type ke fitowa a hankali, kasuwar tantanin halitta ta PERC ta ragu zuwa 73.0%. Tantanan halitta na N-type sun kai jimlar kusan 26.5%, tare da tantanin halitta na N-type TOPCon kusan 23.0%, tantanin halitta na heterojunction kusan 2.6%, da tantanin halitta na XBC kusan 0.9%—dukkan haɓaka mai yawa akan 2022.

Daga 2024 zuwa gaba, rabon tantanin halitta na N-type wanda TOPCon ke wakilta zai wuce P-type PERC gabaɗaya, tare da masana'antar tsammanin rabon zai kai ya wuce 70%.

Ra'ayin Ooitech

Ooitech ta yi imani: TOPCon, fasahar tantanin halitta mai wucewa ta oxide passivated contact na N-type wanda ke gina kan layukan PERC da ake da su, yana ba da inganci mafi girma, ƙarancin lalacewa, da ƙarfin samar da wutar lantarki, kuma yanzu ya zama babban abin da masana'antar hasken rana ke bi.