GaAs radiation imaging detectors with an active layer thickness up to 1 mm

Unlike conventional GaAs detector structures that use a space charge region (SCR) of a barrier structure, we propose to form a detector structure of resistor type made of GaAs compensated with Cr. In this case, the electric field distribution, ξ(x), is not screened by the ion concentration in the SCR but it is defined only by the uniformity of the distribution of the resistance value in the structure. The experimental results on measurements of the electrophysical characteristics and the electric field distribution are presented. It is shown that in these structures the electric field distribution is uniform through the whole high-resistive layer with a thickness up to 1 mm. The possibility of achieving high values of charge collection efficiency of gamma-radiation is demonstrated.