中国物理B ›› 2015, Vol. 24 ›› Issue (3): 38801-038801.doi: 10.1088/1674-1056/24/3/038801

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Boron implanted emitter for n-type silicon solar cell

梁鹏, 韩培德, 范玉洁, 邢宇鹏   

  1. State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • 收稿日期:2014-09-27 修回日期:2014-10-23 出版日期:2015-03-05 发布日期:2015-03-05
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61275040, 60976046, and 61021003) and the National Basic Research Program of China (Grant No. 2012CB934200).

Boron implanted emitter for n-type silicon solar cell

Liang Peng (梁鹏), Han Pei-De (韩培德), Fan Yu-Jie (范玉洁), Xing Yu-Peng (邢宇鹏)   

  1. State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
  • Received:2014-09-27 Revised:2014-10-23 Online:2015-03-05 Published:2015-03-05
  • Contact: Liang Peng E-mail:liangpeng@semi.ac.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 61275040, 60976046, and 61021003) and the National Basic Research Program of China (Grant No. 2012CB934200).

摘要:

The effects of ion doses on the properties of boron implanted Si for n-type solar cell application were investigated with doses ranging from 5× 1014 cm-2 to 2× 1015 cm-2 and a subsequent two-step annealing process in a tube furnace. With the help of the TCAD process simulation tool, knowledge on diffusion kinetics of dopants and damage evolution was obtained by fitting SIMS measured boron profiles. Due to insufficient elimination of the residual damage, the implanted emitter was found to have a higher saturation current density (J0e) and a poorer crystallographic quality. Consistent with this observation, Voc, Jsc, and the efficiency of the all-implanted p+-n-n+ solar cells followed a decreasing trend with an increase of the implantation dose. The obtained maximum efficiency was 19.59% at a low dose of 5× 1014 cm-2. The main efficiency loss under high doses came not only from increased recombination of carriers in the space charge region revealed by double-diode parameters of dark I-V curves, but also from the degraded minority carrier diffusion length in the emitter and base evidenced by IQE data. These experimental results indicated that clusters and dislocation loops had appeared at high implantation doses, which acted as effective recombination centers for photogenerated carriers.

关键词: boron implanted emitter, n-type silicon, clusters and dislocation loops, saturation current density

Abstract:

The effects of ion doses on the properties of boron implanted Si for n-type solar cell application were investigated with doses ranging from 5× 1014 cm-2 to 2× 1015 cm-2 and a subsequent two-step annealing process in a tube furnace. With the help of the TCAD process simulation tool, knowledge on diffusion kinetics of dopants and damage evolution was obtained by fitting SIMS measured boron profiles. Due to insufficient elimination of the residual damage, the implanted emitter was found to have a higher saturation current density (J0e) and a poorer crystallographic quality. Consistent with this observation, Voc, Jsc, and the efficiency of the all-implanted p+-n-n+ solar cells followed a decreasing trend with an increase of the implantation dose. The obtained maximum efficiency was 19.59% at a low dose of 5× 1014 cm-2. The main efficiency loss under high doses came not only from increased recombination of carriers in the space charge region revealed by double-diode parameters of dark I-V curves, but also from the degraded minority carrier diffusion length in the emitter and base evidenced by IQE data. These experimental results indicated that clusters and dislocation loops had appeared at high implantation doses, which acted as effective recombination centers for photogenerated carriers.

Key words: boron implanted emitter, n-type silicon, clusters and dislocation loops, saturation current density

中图分类号:  (Silicon solar cells)

  • 88.40.jj