Properties of a-Si:H and a-(Si, Ge):H Solar Cells Prepared Using ECR Deposition Techniques

In this paper, we describe the device preparation, properties and stability of a-Si:H and a-(Si,Ge):H solar cells prepared using the electron cyclotron resonance (ECR) plasma deposition techniques. We show that by controlling the plasma chemistry, we can produce very good devices in the substrate geometry in a single chamber reactor. Both single junction and tandem junction a-Si:H solar cellshave been prepared with high fill factors and good voltages. The stability of these devices is excellent. We have also prepared graded gap a-(Si,Ge):H cells, and they also show very good stability upon light soaking. We find that the properties of a-(Si,Ge):H cells depend critically upon the plasma conditions, and that controlled ion bombardment may be beneficial for improving the performance ofthese cells.