High Performance Diamond Thin Film Cold Cathode.

摘要

In this reporting period, we have investigated the low power performance of amorphic diamond thin films deposited under various conditions such as laser power, thickness, gas pressure and background vacuum. We have found that higher power density gives better field emission. This has been correlated to a large number of particles on the sample which seems to increase with increased power density. In addition, the best films seem to have a bulk resistivity in the few hundred ohm-cm range. The reason for this is not very well understood at this time. During these investigations, we have found a phenomenon, which we call 'conditioning'. Conditioning shows several successive I-V curves taken on the same point on an amorphic diamond sample. It is seen that a relatively high voltage is required to turn on electron emission when the voltage is applied for the first time. After the first turn-on, the voltage required to emit the same current is decreased.