Thick film PN‐junctions based on mixed oxides of indium and silicon as gamma radiation sensors

Indium oxide (In₂O₃) and silicon oxide (SiO) mixtures in the form of thick films pn‐junctions were investigated for gamma radiation dosimetry purposes. Polymer pastes of In₂O₃ and SiO mixtures in various proportions were made of 92 wt per cent of functional material and 8 wt per cent of PVB, while ethyleneglycolmonobutylether was used as a solvent. Raman spectroscopy and X‐ray diffraction (XRD) of the films readily endorse the formation of a mixed silicon oxide and indium oxide coating. All devices were exposed to a disc‐type ¹³⁷Cs source with an activity of 370 kBq. The I‐V characteristics for the samples were measured after each exposure dose. Results show that the current is increased with the increase in radiation dose to a certain level, exceeding this level resulted in unstable dosimetric characteristics and device damage. The performance parameters of the devices, such as sensitivity to γ‐radiation exposure and working dose region, were found to be highly dependant on the composition of the materials used.