Influence of the microstructure on the charge transport in semiconductor gas discharge electronic devices

Abstract Experimental results with nonlinear features and hysteresis characteristics in the pre-breakdown Townsend discharge regime is studied experimentally for a planar microstructure with a GaAs photocathode, an interelectrode gap thickness of 445 μ m and gas pressure in the range 28–66 Torr. An investigation of the effect of the voltage amplitude on the dynamics of transient processes in the semiconductor gas discharge microstructure was made to explain the mechanism of the current decay. A linearly increasing voltage (i.e.  3 V s − 1 and 5 V s − 1 voltage rate) was applied to the system to study current instability. The nonlinear transport mechanism of carriers through the cross-section of the discharge gap i.e. the appearance of the spatio-temporal self-organization of a nonlinear dissipative system, non-equilibrium electron motion and autocatalytic effect of carrier accumulation in the gas layer attributed to decrease of current with the increase of applied voltage. It is established that the pre-breakdown current decreases anomalously with increase of the feeding voltage and illumination intensity on the photocathode. The current density change through the cross-section of the discharge gap, i.e. the appearance of the spatio-temporal self-organization of nonlinear dissipative systems, causes these observed effects. On the other hand, the oscillatory current with non-monotonic N -shaped and hysteresis peculiarities in post-breakdown region is known to be related to a nonlinear mechanism of carrier transport in the semiconductor material caused by EL2 defect centres.