Ohmic Contact Properties of Magnesium Evaporated onto Undoped and P-doped a-Si: H

We have investigated the current-voltage characteristics of metal/undoped a -Si: H/ n + (or p + ) c -Si structures using Mg, Au, Pt and Al. It has been indicated that the energy band of undoped a-Si: H shows a downward bending against Mg, being analogous to n + a -Si: H/undoped a -Si: H contact, while the band shows an upward bending against Au, Pt and Al. Mg/undoped a -Si: H contact is found to allow injection of electrons into the conduction band of a -Si: H, providing us a good ohmic contact property. This contact does not exhibit the thermal-degradation at least up to 100°C.