低表面浓度磷掺杂的高方阻P-N结发射极制备工艺

摘要/Abstract

摘要： 制备P-N结发射极的常规扩散工艺主要包括预淀积和高温推阱两个步骤。本文采用在高温推阱之后施加一步保温过程的工艺方案,在p型多晶硅片上制备了低表面浓度磷掺杂的高方阻发射极,研究了不同保温温度对P-N结发射极的方阻和磷原子掺杂分布的影响。结果表明,当完成高温推阱后,在650~750 ℃温度范围内施加保温工艺所得P-N结的方阻值反向升高,同时二次离子质谱(SIMS)测试结果表明,硅片表层区域的磷原子掺杂浓度相应降低。与常规扩散工艺相比,采用在700 ℃下保温15 min时所得P-N结的方阻升高约3.2 Ω/□,所得相应太阳能电池光电转换效率E_ff达到18.69%,比产线工艺提高约0.23%。

关键词: 太阳能电池, P-N结, 磷掺杂, 扩散, 掺杂浓度, 光电转换, 转换效率

Abstract: The conventional thermal diffusion process for preparing P-N junction emitter of solar cells mainly consists of two steps: pre-deposition and high temperature drive-in. In this paper, high sheet resistance (R_s) emitters with a low surface phosphorus doping concentration were prepared on p-type multicrystalline silicon wafers by introducing a constant temperature process after the high temperature drive-in step. The influence of constant temperature on the R_s and phosphorus atom doping profile of P-N junction emitter was investigated. The results show that the R_s of the P-N junction with a certain constant temperature treatment can increase reversely. Correspondingly, the doping profiles tested by secondary ion mass spectrometry (SIMS) indicate that the phosphorus doping concentration at the surface of silicon was reduced when the constant thermal treatment at temperatures of 650 ℃ to 750 ℃ was carried out after the high temperature drive-in step. Compared with the conventional diffusion process, the R_s of the P-N junction with a constant temperature treatment at 700 ℃ for 15 min increased by about 3.2 Ω/□, and the conversion efficiency E_ff of the corresponding solar cells increases to 18.69%, which is higher by 0.23% than that of the Baseline.

Key words: solar cell, P-N junction, phosphorus doping, diffusion, doping concentration, photoelectric conversion, conversion efficiency

中图分类号:

TM914.4

李旺, 唐鹿, 田娅晖, 薛飞, 辛增念, 潘胜浆. 低表面浓度磷掺杂的高方阻P-N结发射极制备工艺[J]. 人工晶体学报, 2022, 51(1): 132-138.

LI Wang, TANG Lu, TIAN Yahui, XUE Fei, XIN Zengnian, PAN Shengjiang. Process of Preparing High Sheet Resistance P-N Junction Emitter with Low Surface Phosphorus Doping Concentration[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2022, 51(1): 132-138.

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