Materials and photosensor devices with high radiation stability

摘要

Semiconductor Hg_3In_2Te_6 crystals and their analogous are solid solutions of In_2Te_3 and HgTe. Hg_3In_2Te_6 crystals are congruently melted as chemical compound. Like In_2Te_3 the Hg_3In_2Te_6 crystal has cubic crystal lattice with stoichiometric vacancies in their crystal structure. The electroconductivity, photoconductivity, mechanical, chemical properties of the crystals do not deteriorate after their irradiation by γ-photons with energies up to 1 MeV and doses up to 1018 cm~(-2), by electrons with energies up to 300 MeV and doses up to 1019 cm~(-2) and by mixed reactor irradiation (filtered slow neutrons) with doses up to 1019 cm~(-2). This feature is determined by high concentration (～10~(21) cm~(-3)) of stoihiometric vacancies (Vs) in crystal structure, where every third In-cation node is empty. These V_s are electroneutral, they capture all impurity atoms in these crystals and kept them in electroneutral state too. On the other hand, this feature does not allow forming direct p-n junctions in these crystals by introducing the impurities. However, we have developed p-n junction analogues in form of Schottky diodes and corresponding photodiodes with semitransparent metal layer on single crystal Hg_3In_2Te_6 substrate that allows irradiation to get into active region preserving this way all the advantages compared to p-n junction.