Theoretical investigation on the passivation layer with linearly graded bandgap for the amorphous/crystalline silicon heterojunction solar cell. Issue 10 (5th September 2016)

• Record Type: Journal Article
• Authors: Zhao, Lei; Wang, Guanghong; Diao, Hongwei; Wang, Wenjing
• Is Part Of: Physica status solidi. Volume 10:Issue 10(2016)
• Page Start: 730
• Page End: 734
• Publication Date: 2016-09-05
• Subjects: passivation layers -- amorphous materials -- crystals -- silicon -- heterojunctions -- solar cells; Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201600246
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : Passivation layer with linearly graded bandgap (LGB) was proposed to improve the performance of amorphous/crystalline silicon heterojunction (SHJ) solar cell by eliminating the large abrupt energy band uncontinuity at the a‐Si:H/c‐Si interface. Theoretical investigation on the a‐Si:H(p)/the LGB passivation layer(i)/c‐Si(n)/a‐Si:H(i)/a‐Si:H(n + ) solar cell via AFORS‐HET simulation show that such LGB passivation layer could improve the solar cell efficiency ( η ) by enhancing the fill factor (FF) greatly, especially when the a‐Si:H(p) emitter was not efficiently doped and the passivation layer was relatively thick. But gap defects in the LGB passivation layer could make the improvement discounted due to the open‐circuit voltage ( V OC ) decrease induced by recombination. To overcome this, it was quite effective to keep the gap defects away from the middle of the bandgap by widening the minimum bandgap of the LGB passivation layer to be a little larger than that of the c‐Si base. The underlying mechanisms were analysed in detail. How to achieve the LGB passivation layer experimentally was also discussed. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) Abstract : Passivation layer with linearly graded bandgap (LGB) was proposed to improve the performance of amorphous/crystalline silicon heterojunction (SHJ) solar cell by eliminating the spike‐like barrier occurring at a‐Si:H/c‐Si interface. Theoretical simulation shows that such LGB passivation layer could improve the solar cell efficiency ( η ) by enhancing the fill factor (FF) greatly, especially when the passivation layer was relatively thick, which would be very helpful for the real solar cell fabrication.