15% Efficiency Ultrathin Silicon Solar Cells with Fluorine-Doped Titanium Oxide and Chemically Tailored Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) as Asymmetric Heterocontact

Jian He; Md Anower Hossain; Hao Lin; Wenjie Wang; Siva Krishna Karuturi; Bram Hoex; Jichun Ye; Pingqi Gao; James Bullock; Yimao Wan

doi:10.1021/acsnano.9b01754

15% Efficiency Ultrathin Silicon Solar Cells with Fluorine-Doped Titanium Oxide and Chemically Tailored Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) as Asymmetric Heterocontact

ACS Nano. 2019 Jun 25;13(6):6356-6362. doi: 10.1021/acsnano.9b01754. Epub 2019 Apr 26.

Authors

Jian He^{1

2}, Md Anower Hossain³, Hao Lin⁴, Wenjie Wang¹, Siva Krishna Karuturi¹, Bram Hoex³, Jichun Ye⁴, Pingqi Gao⁵, James Bullock², Yimao Wan¹

Affiliations

¹ Research School of Engineering , The Australian National University , Canberra , ACT 2602 , Australia.
² Electrical & Electronic Engineering Department , University of Melbourne , Melbourne , VIC 3052 , Australia.
³ School of Photovoltaic and Renewable Energy Engineering , University of New South Wales , Sydney , NSW 2052 , Australia.
⁴ Ningbo Institute of Material Technology and Engineering , Chinese Academy of Sciences , Ningbo 315201 , China.
⁵ School of Materials , Sun Yat-sen University , Guangzhou 510275 , China.

PMID: 31017761
DOI: 10.1021/acsnano.9b01754

Abstract

In order to achieve a high performance-to-cost ratio to photovoltaic devices, the development of crystalline silicon (c-Si) solar cells with thinner substrates and simpler fabrication routes is an important step. Thin-film heterojunction solar cells (HSCs) with dopant-free and carrier-selective configurations look like ideal candidates in this respect. Here, we investigated the application of n-type silicon/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) HSCs on periodic nanopyramid textured, ultrathin c-Si (∼25 μm) substrates. A fluorine-doped titanium oxide film was used as an electron-selective passivating layer showing excellent interfacial passivation (surface recombination velocity ∼10 cm/s) and contact property (contact resistivity ∼20 mΩ/cm²). A high efficiency of 15.10% was finally realized by optimizing the interfacial recombination and series resistance at both the front and rear sides, showing a promising strategy to fabricate high-performance ultrathin c-Si HSCs with a simple and low-temperature procedure.

Keywords: asymmetric heterocontacts; electron-selective contact; passivating contact; titanium oxide; ultrathin c-Si.