Effects of substrate characteristics on the passivation performance of ALD-Al_2O_3 thin film for high-efficiency solar cells

作     者：梁宗存 王殿磊 朱彦斌 

作者机构：School of Physics and Engineering Institute for Solar Energy Systems State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University 

出 版 物：《Journal of Semiconductors》 (半导体学报（英文版）)

年 卷 期：2014年第35卷第5期

页      面：26-31页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China(No.61176055) the Science and Technology Project of Guangdong Province,China(No.2011A080804009) 

主　　题：atom layer deposition （ALD）-Al2O3 passivation minority carrier lifetime surface recombinationvelocity solar cell 

摘      要：Atom layer deposition （ALD）-Al2O3 thin films are considered effective passivation layers for p-type silicon surfaces. A lower surface recombination rate was obtained through optimizing the deposition parameters. The effects of some of the basic substrate characteristics including material type, bulk resistivity and surface morphology on the passivation performance of ALD-Al2O3 are evaluated in this paper. Surface recombination velocities of 7.8 cm/s and 6.5 cm/s were obtained for p-type and n-type wafers without emitters, respectively. Substrates with bulk resistivity ranging from 1.5 to 4 Ω · cm were all great for such passivation films, and a higher implied Voc of 660 mV on the 3 Ω · cm substrate was achieved. A minority carrier lifetime （MCL） of nearly 10 μs higher was obtained for cells with a polished back surface compared to those with a textured surface, which indicates the necessity of the polishing process for high-efficiency solar cells. For n-type semi-finished solar cells, a lower effective front surface recombination velocity of 31.8 cm/s was acquired, implying the great potential of （ALD）-Al2O3 thin films for high-efficiency n-type solar cells.