Properties of post-hydrogenated amorphous and microcrystalline germanium films

Amorphous and microcrystalline germanium films prepared by glow-discharge and molecular beam deposition were hydrogenated after deposition, using a 3cm Kaufman ion source. The hydrogen profiles were determined using the N/sup 15/p nuclear resonance reaction. The authors found that the surface region hydrogen concentration depended on ion beam modification of the material, and the bulk concentration was determined by the hydrogenation conditions and deposition conditions. The light and dark conductivities were measured before and after hydrogenation. Several orders of magnitude change in the ratios of the conductivities were measured under optimum hydrogenation conditions. The activation energy for electrical conductivity was measured and found to be dependent on film structure thickness and hydrogenation conditions