Laser annealing of silicon surface defects for photovoltaic applications

SURFACE SCIENCE

卷:652

Article

Sun, Zeming¹  Gupta, Mool C.¹ 

[1] Univ Virginia, Charles L Brown Dept Elect & Comp Engn, Charlottesville, VA 22903 USA

关键词: Laser annealing;    Defects;    Silicon;    Photovoltaics;    Photoluminescence;   

DOI  :  10.1016/j.susc.2016.03.028

来源: Elsevier

【 摘 要 】

High power lasers are increasingly used for low cost fabrication of solar cell devices. High power laser generate crystal defects, which lower the cell efficiency. This study examines the effect of low power lasering for the removal of high power laser induced surface defects. The laser annealing behavior is the significant decrease of photoluminescence generated from dislocation-induced defects and the band-to-band emission. This annealing effect is further confirmed by the X-ray diffraction peak reversal. The location density is quantified by observing etch pits under the scanning electron microscope (SEM). For melted samples, the dislocation density is decreased to as low as 1.01 x 10(6) cm(-2) after laser annealing, in an excellent surface carrier lifetime of 920 mu s that is comparable to the value of 1240 ps for the silicon wafer. For severely defective samples, the dislocation density is decreased by 4 times and the surface carrier time is increased by 5 times after laser annealing. (C) 2016 Elsevier B.V. All rights reserved.

【 授权许可】

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