Abstract
Hydrogenated amorphous silicon thin films were grown by plasma enhanced chemical vapor deposition onto coated glass substrates or n-Si wafers and were investigated for their electron field emission. The observed emission current did not fit a Fowler-Nordheim type tunneling current, but was closer to a space charge limited current which would be expected if the current limiting process was due to space charge. The observed decrease and turning off of the emission current with time can be addressed by pulsed mode operation and surface charge extraction via a gate electrode. Multilayer structures that contain Schottky and ohmic back contacts as well as thin 15 nm n+ surface layers used to control the potential of the front surface of the emitting device.