Influence of photodetector peculiarities on the operation of an ionization type IR image converter

Photodetector instabilities of an IR image converter is studied experimentally in a wide range of the gas pressures, interelectrode distances and different diameters of the detector areas. While being driven with a stationary voltage, it generates current and discharge light emission (DLE) instabilities with different amplitudes of the oscillation. It has been unambiguously proved that instabilities in the semiconductor gas discharge structure may be provoked by a photodetector, depending on the experimental conditions. A semiconductor gas discharge structure with an N-shaped CVC was analyzed using both the current and DLE data showing the electrical instability in the GaAs photodetector. It was found that application of high feeding voltage to this photodetector give rise to non-uniform spatial distribution of the DLE, which disturbed the operation of the system. The experiment presents also a new method to study and visualization of the electrical instabilities in high resistivity IR photodetector of large diameter