High-Performance and Traditional Multicrystalline Silicon: Comparing Gettering Responses and Lifetime-Limiting Defects
High-Performance and Traditional Multicrystalline Silicon: Comparing Gettering Responses and Lifetime-Limiting Defects
复制标题
高性能和传统多晶硅：比较吸杂响应和寿命限制缺陷
DOI：
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发表时间：
2016
影响因子：
3
通讯作者：
T. Buonassisi
中科院分区：
文献类型：
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作者：
S. Castellanos;K. Ekstrøm;Antoine Autruffe;M. Jensen;A. Morishige;J. Hofstetter;Patricia X. T. Yen;B. Lai;G. Stokkan;C. del Cañizo;T. Buonassisi
近年来，高性能多晶硅（HPMC-Si）已成为传统锭基多晶硅（mc-Si）的一个有吸引力的替代品，具有相似的成本结构，但提高了电池性能。在此，我们评估了传统mc-Si和HPMC-Si的吸光响应。微量分析表明，HPMC-Si和mc-Si具有相似的寿命限制缺陷类型，但具有不同的相对浓度和分布。与mc-Si相比，HPMC-Si在吸磷后的寿命显著提高，这主要是由于富位错簇的面积分数较低。在两种材料中，位错团簇和晶界与扩散后相对较高的间隙铁点缺陷浓度相关，这表明存在溶解的金属杂质沉淀。HPMC-Si中相对较少的位错团簇显示出与mc-Si相似的特征。考虑到类似的控制原则，确定mc-Si的位错团簇相对重组活性的代理被成功地转移到HPMC-Si。发现HPMC-Si材料的剩余寿命受到晶界复合的限制。为了降低HPMC-Si中晶界的复合活性，必须在生长、吸附和钝化过程中进行协调的杂质控制。
In recent years, high-performance multicrystalline silicon (HPMC-Si) has emerged as an attractive alternative to traditional ingot-based multicrystalline silicon (mc-Si), with a similar cost structure but improved cell performance. Herein, we evaluate the gettering response of traditional mc-Si and HPMC-Si. Microanalytical techniques demonstrate that HPMC-Si and mc-Si share similar lifetime-limiting defect types but have different relative concentrations and distributions. HPMC-Si shows a substantial lifetime improvement after P-gettering compared with mc-Si, chiefly because of lower area fraction of dislocation-rich clusters. In both materials, the dislocation clusters and grain boundaries were associated with relatively higher interstitial iron point-defect concentrations after diffusion, which is suggestive of dissolving metal-impurity precipitates. The relatively fewer dislocation clusters in HPMC-Si are shown to exhibit similar characteristics to those found in mc-Si. Given similar governing principles, a proxy to determine relative recombination activity of dislocation clusters developed for mc-Si is successfully transferred to HPMC-Si. The lifetime in the remainder of HPMC-Si material is found to be limited by grain-boundary recombination. To reduce the recombination activity of grain boundaries in HPMC-Si, coordinated impurity control during growth, gettering, and passivation must be developed.