Nanosecond electron beam controlled switching

Results of electron beam controlled switching in zinc selenide (ZnSe), quartz, and preliminary results in sapphire are analyzed. Initial tests yielded indistinguishable data for charging voltages between 0.1 to 1 kV. For later tests, introduction of a ground plane with an opening in front of the sample reduced beam "noise" by an order of magnitude for some ZnSe samples, resulting in data obtained for small charging voltages on the order of 100 V and up. In all cases, switch resistance was drastically reduced in response to the electron beam. The ZnSe switch recovery was exponential, whereas the quartz samples showed nearly instantaneous on/off response to the e-beam. Preliminary sapphire tests showed a switching response to the e-beam.