Kovalchuk M. Photodetectors based on the solid solutions HgTe

The dissertation presents the results of integrated developments in the sphere of synthesis and growth methods and studies of structural, electrical, optical, photoelectrical properties of graded band-gap structures based on mercury telluride solid solutions with telluride of bivalent metals; bottom layer crystals for them, and crystals of mercury telluride solid solutions with telluride of trivalent metals and creation on their basis of electrical, optical, photoelectrical devices and research of their quality. The reasons for formation of SiO2 precipitates in CdTe and Cd1-yMnyTe crystals during growth have been discovered by means of electron-probe analysis. T-X diagram of state of Cd-CdTe-Sb system has been studied. The temperature dependencies of electric conductivity and Hall's effect within 80-350 K on the CdxMnyHg1-x-yTe graded band-gap structures have been analyzed; tunable optical IR filters, photodetectors, spectrometric elements have been created on their basis. Radially homogeneous in composition and physical properties radiostable crystals of mercury telluride solid solutions with tellurides of trivalent metals have been grown. These are In2Hg3Te6 crystals and their analogs - InGaHg2CdTe6, InGaHg2MnTe6. The differential thermal analysis has shown them to melt and crystallize congruently. The X-ray diffraction analysis helped to establish their structural type, lattice constants; and studies of electrical, optical, photoelectrical properties helped to determine the values of their energy gaps. On this basis, the diodes and Schottky photodiodes were created that were subject to full complex of measuring electric and photoelectric properties and parameters prior to and after beta-, gamma- irradiation. It has been uncovered that gamma-radiation doses up to 10^8 Rem almost do not change the photoelectric parameters of the above described Schottky photodiodes, hence they are recommended as IR radiation-resistant photodetectors within the spectral range of =0,8-1,6 mkm and as detectors with wide dynamic range of х-, beta-, gamma-, neutron radiation.