Effect of Phosphorus and Boron Diffusion Gettering on the Light Induced Degradation in Multicrystalline Silicon Wafers. (September 2017)

• Record Type: Journal Article
• Authors: Chakraborty, Sagnik; Wilson, Marshall; Manalo, Maria Luz; Sarda, Abhay; Wong, Johnson; Sharma, Romika; Aberle, Armin G.; Li, Joel B.
• Is Part Of: Energy procedia. Volume 130(2017)
• Page Start: 36
• Page End: 42
• Publication Date: 2017-09
• Subjects: High-performance multicrystalline silicon -- phosphorus diffusion gettering (PDG) -- boron diffusion gettering (BDG) -- ICP-MS -- trace metal impurities -- diffusion; Power resources -- Congresses; Power resources -- Periodicals; Power resources; Conference proceedings; Periodicals; 333.7905
• DOI: 10.1016/j.egypro.2017.09.411
• Languages: English
• ISSNs: 1876-6102

Abstract

Abstract: Multicrystalline silicon (multi-Si) is currently the most widely used material for crystalline silicon solar cells. Although there has been substantial improvement in cell efficiency with the use of high-performance (HP) multi-Si, the PERC (passivated emitter and rear cell) devices fabricated from this material suffer from strong light-induced degradation (LID). This study aims to investigate the possibility of reducing LID in HP multi-Si wafers using diffusion gettering. By using inductively coupled plasma mass spectrometry, we measured the impurity concentration in sister samples subjected to different diffusion conditions. The results showed that a 50-Ω/sq POCl3 diffusion and 60-Ω/sq BBr3 diffusion at 800°C can getter impurities effectively. The interstitial Fe (Fei ) and light-induced defect concentration was measured before and after gettering, using surface photovoltage measurements. After degrading the samples at 80°C for 24 hours, we observed that the light-induced defect concentration is lowest in HP multi-Si wafers that underwent phosphorus diffusion gettering. Samples subjected to boron diffusion gettering also show less LID compared to non-diffused sister samples.