Development of new concept solar cell by utilizing natural superlattice

CuO_2晶体结构是由垂直于c轴的p层和n层堆叠而成，因此被选为新概念太阳能电池的候选材料。我们用射频溅射方法制备了c轴垂直于衬底表面而不平行于衬底表面的CuInO2薄膜：平行薄膜仅用PLD方法制备。遗憾的是，我们不能展示新概念的含CuO_2的太阳电池，但是，用UPS测定了CuO_2的两个重要参数--电离势和电子亲和势，从而揭示了CuO_2双极导电的起源。

CuInO_2 was selected as a candidate material for new concept solar cell because its crystal structure is composed of stacking of p-and n-layers perpendicular to its c-axis. We have prepared CuInO2 films whose c-axis perpendicular to substrate surface but not parallel ones by RF sputtering method : The parallel films were only prepared by using PLD method. Unfortunately, we could not demonstrate new concept solar cell with CuInO_2, however, important two parameters of CuInO_2, ionization potential and electron affinity, were determined by UPS and the origin of the bipolar conduction in CuInO_2 has been revealed.