Metal-insulator-semiconductor solar cells with silicon oxynitride tunnel insulator by using rapid thermal processing

Metal-insulator-semiconductor (MIS) solar cells were prepared with silicon oxynitride as tunnel insulator by using rapid thermal processing (RTP). During the reaction of NH3 at the silicon surface the growing of the oxynitride layer was investigated at temperatures up to 950 °C and layer thicknesses up to 2 nm. The elemental composition of the layer was characterized by using Auger electron spectroscopy (AES). Extensive electrical characterizations on MIS tunnel diodes and MIS cells were carried out and an improved thermal stability (up to 350 °C) of the Al-oxynitride-silicon system was found in comparison to the conventional silicon oxide as a tunnel insulator up to 270 °C.