Fundamental and applied aspects of physical characteristics of polycrystalline samples of oxide semiconductor (In$_2$O$_3$)$_{1-x}$ : (SrO)$_x$

The electrical and structural characteristics of polycrystalline samples of indium oxide with varying levels of strontium doping have been studied. These allow the formation of unusual sensory properties of the oxide functional material, which are manifested in a broadband photoconductivity effect and increased sensitivity to the effects of humidity and oxidizing gases. It has been established that the maximum photoconductivity effect is realized in the high-resistance state of the samples, which is achieved by selecting a coordinated content in the material of impurity acceptor states and intrinsic electrically active defects in the form of oxygen vacancies. It is shown that the photosensitivity of the samples is manifested due to the formation of a spatial relief of the conduction zone, which even at a high level of doping ($x$ = 0.1) can be suppressed without changing the cationic composition of the sample by significantly increasing the concentration of oxygen vacancies within the framework of the sample heat treatment procedure at a relatively low temperature $T$ = 300–400$^\circ$C.