HITTM cells—high‐efficiency crystalline Si cells with novel structure

Our unique, high‐efficiency c‐Si solar cell, named the HIT cell, has shown considerable potential to improve junction properties and surface passivation since it was first developed. The improved properties in efficiency and temperature dependence compared to conventional p – n diffused c‐Si solar cells are featured in HIT power 21^TM solar cell modules and other applications which are now on the market. In the area of research, further improvement in the junction properties of the a‐Si/c‐Si heterojunction has been examined, and the highest efficiency to date of 20.1% has recently been achieved for a cell size of 101 cm². The high open circuit voltage exceeding 700 mV, due to the excellent surface passivation of the HIT structure, is responsible for this efficiency. In this paper, recent progress in HIT cells by Sanyo will be introduced. Copyright © 2000 John Wiley & Sons, Ltd.