Excellent c-Si surface passivation by industrial firing activation of thermal atomic layer deposited Al2O3
In this work we demonstrate that by using an H2O based thermal atomic layer deposited (ALD) Al2O3 film,excellent surface passivation (close to 10 ms effective lifetime) on un-diffused silicon wafers can be achieved after direct firing activation of the Al2O3 passivation layer using a fast industrial high-temperature firing step as required for contact formation via screen printing.Neither a low-T post-deposition anneal nor a SiNx capping layer is required.Deposition temperatures in the 100-400℃ range and peak firing temperatures of ~800℃ (set temperature) were investi-gated.Using industrially relevant Cz wafers (pseudosquare,125 mm wide,n-type,~5 Ωcm resistivity,thickness ~140 μm),effective lifetimes of around 4 ms were obtained.Using FZ wafers (4 diameter,n-type,~2.5 Ω cm,~280 μm thick),effective lifetimes close to 10 ms were reached.Capaci-tance-voltage (C-V) measurements revealed a fixed negative interface charge density of -3.3×1012 cm-2 and a midgap interface defect density of 1.2.1011 cm-2 eV-1 after firing.
B.Liao B.Hoex R.Stangl T.Mueller F.Lin Z.Qiu A.J.Danner H.Yang A.G.Aberle C.S.Bhatia
Solar Energy Research Institute of Singapore(SERIS), National University of Singapore(NUS), 7 Engine Solar Energy Research Institute of Singapore(SERIS), National University of Singapore(NUS), 7 Engine Electrical and Computer Engineering Department, National University of Singapore, 4 Engineering Driv Solar Energy Research Institute of Singapore(SERIS), National University of Singapore(NUS), 7 Engine
国际会议
The 22nd International Photovoltaic Science and Engineering Conference (第22届国际光伏科学与工程会议)
杭州
英文
1-4
2012-11-05（万方平台首次上网日期，不代表论文的发表时间）