Regularities of X-ray Transfer in Doped Multicomponent Semiconductors for Dosimetry

Sensitivity control of semiconductors often requires changing their crystal and electronic structure, which can lead to the loss of their initial semiconductor properties. Chalcogenide semiconductors have high carrier transport properties. However, they face limitations in detecting hard X-rays due to various reasons, in particular, their defective structure and poor X-ray sensitivity. The basic laws of the theory of X-ray conductivity of semiconductors are generalized and simplified taking into account their areas of application. The features of the influence of doping on X-ray sensitivity, determination of the optimal concentration of the dopant, using the example of Cr-doping of chalcogenides, as well as the principle of creating an X-ray detector are considered. As an example of an important X-ray sensitive material, our results on the study of photo- and X-ray conductivity in the layered compound with a monoclinic p-type structure TlGaS2 containing a doped chromium impurity are presented. Our experimental results of the study of synthesized and grown single crystals of chromium-doped (≤0.5 mol % Cr) TlGaS2:Cr are presented. It is shown that TlGaS2:Cr-based materials retain semiconductor properties and are characterized by high electrical transport. Chromium doping increases photosensitivity and polarization between metal and chalcogenide ions in TlGaS2:Cr. The doping of Cr impurity on the photoconductivity and band gap of the layered TlGaS2 single crystal was studied. The change in the spectral sensitivity region of TlGaS2:Cr and the appearance of impurity photocurrent peaks in the photon energy region were analyzed. The X-ray dosimetric properties of TlGaS2:Cr were studied depending on the irradiation doses. Using TlGa0.995Cr0.005S2 as an example, it was shown that the volt-dose characteristics have good reproducibility. The single crystal detector sample TlGa0.995Cr0.005S2 also demonstrated high photo- and X-ray sensitivity compared to pure TlGaS2. The obtained new photoelectric and X-ray dosimetric properties and results show the potential of TlGaS2:Cr semiconductor for optoelectronic and radiation technologies.