Analysis of the double-layer α-Si:H emitter with different doping concentrations for α-Si:H/c-Si heterojunction solar cells

Abstract

Double-layer emitters with different doping concentrations (DLE) have been designed and prepared for amorphous silicon/crystalline silicon (α-Si:H/c-Si) heterojunction solar cells. Compared with the traditional single layer emitter, both the experiment and the simulation (AFORS-HET, http://www.paper.edu.cn/html/releasepaper/2014/04/282/) prove that the double-layer emitter increases the short circuit current of the cells significantly. Based on the quantum efficiency (QE) results and the current-voltage-temperature analysis, the mechanism for the experimental results above has been investigated. The possible reasons for the increased current include the enhancement of the QE in the short wavelength range, the increase of the tunneling probability of the current transport and the decrease of the activation energy of the emitter layers.

Key words： double-layer emitter; α-Si:H/c-Si heterojunction solar cell; short circuit current; quantum efficiency; current-voltage-temperature

Acknowledgments

This work wassupported by the National Natural Science Foundation of China (Grant nos. 61306084, 61464007), Open Fund of Jiangsu Key Laboratory of Materials and Technology for Energy Conversion (Grant no. NJ20160032), and Key Research and Development Program of Jiangxi Province, China (Grant no. 2016BBH80043).

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