Effective surface passivation of crystalline silicon by rf sputtered aluminum oxide

Abstract

In recent years, excellent surface passivation has been achieved on both p-type and n-type surfaces of silicon wafers and solar cells using aluminum oxide deposited by plasmaassisted atomic layer deposition. However, alternative deposition methods may offer practical advantages for large-scale manufacturing of solar cells. In this letter we show that radiofrequency magnetron sputtering is capable of depositing negatively-charged aluminum oxide and achieving good surface passivation both on p-type and n-type silicon wafers. We thus establish that sputtered aluminum oxide is a very promising method for the surface passivation of high efficiency solar cells. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.