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Information × Registration Number 0219U100811, 0116U005334 , R & D reports Title Development of radiation-resistant heterojunctions based on layered materials of indium and gallium monoselenides. popup.stage_title Head Kovaliuk Zakhar D., Registration Date 21-03-2019 Organization Chernivtsi Branch of Frantsevich Institute of Problems of Materials Science popup.description2 Single crystal ingots of intentionally undoped InSe and GaSe and those doped with Cd-, Zn-, In- and Sn-dopants were grown by the Bridgman method. The layered chalcogenides and based on them p-n junctions were irradiated with high-energy electrons (fluence - 10^13-10^15 cm-2, energy - 10 MeV) and gamma-quanta (fluence - 10^13-10^16 cm-2, energy - 3 MeV). First the effect of various e-irradiation doses on electrical properties in the different crystallographic directions is investigated for n-InSe samples with different pristine resistivity. It is found the increase of the anisotropy ratio up to record values (10^7 at 80 К) and detected extremes in the temperature dependences of the Hall coefficient and electron mobility along the layers. The results are explained within a model that predicts, except 3D carriers, the presence of 2D electrons contributing only to transport along the layers. It is established that after irradiation the density of 2D electrons increases by more than a factor of ten. The role of tunnel and activation mechanisms for charge transfer across the layers was analyzed. It is established that after gamma-irradiation of p-InSe - n-InSe, intrinsic oxide - p-InSe and p-GaSe - n-InSe structures their refraction factors, open-circuit voltages, non-ideality factors of CVC, monochromatic ampere- and volt-watt sensitivities become improved. It is shown that high-energy electrons do not affect the photoresponse spectra in the р-GaSe-n-ІnSe, р-n-ІnSe and intrinsic oxide - р-ІnSe structures, in particular exciton's fine structure remains. Detectors of continuum X-radiation based on p-GaSe - n-InSe and CdTe - InSe heterojunctions and an In - GaSe:Sn - In metal - semiconductor structure are developed. Their X-ray sensitivity factor is (2.1-3.2)x10^-8, (0.9-7.0)x10^-9 and (1.0-40)x10^-10 А min/R for metal - GaSe:Sn - metal, р-GaSe - n-ІnSe and CdTe-InSe structures respectively. Product Description popup.authors popup.nrat_date 2020-04-02 Close