Abstract
Recently, the world production of the photovoltaic modules which convert directly solar energy to electricity, is tremendously increasing in the world, and high performance photovoltaic modules are required. An extremely high conversion efficiency of 21.5% has been achieved in the HIT (Hetero-junction with Intrinsic Thin-layer) solar cell with a practical cell size of 10cm×10cm. This was achieved by improving the characteristics of a-Si/c-Si hetero-junction, reduction of light reflection-loss, and so on. Some of these technologies have been introduced to mass production and, as a result, 200W HIT solar cell modules have been commercialized with the highest existing cell conversion efficiency of 19.5%.
