Helium cryostat with oil-free pumping to irradiate the semiconductor with electrons and measure in situ its optical characteristics

摘要

The utility model refers to cryogenic equipment. It is a demountable cryostat that allows irradiation of samples of semiconductor crystals with low-energy (up to 10 keV) electrons in high (at least 10) at a liquid helium temperature (4.2 K)^-9mm. Hg) vacuum and in situ to register their optical spectra. The proposed cryostat can be used to investigate the radiation resistance of semiconductor crystals A²AT^6th by their spectra of luminescence, reflection and absorption of light.;The task for solving the useful model is to improve the method for studying the surface properties of semiconductors based on their irradiation by low-energy (several keV) electrons in vacuum at a temperature of T = 4.2 K and in situ measurement of their optical spectra.;This problem is achieved by means of a helium cryostat with oil-free pumping to irradiate the semiconductor with electrons and measuring in situ its optical characteristics consisting of an external non-separable glass Dewar nitrogen vessel and an internal collapsible Helium Dewar vessel with an electron gun. In this case, the preliminary vacuum in a helium vessel is created by an oil-free (sorption) pump, and all separable and integral connections of the vessel parts with each other are performed without the use of a vacuum lubricant.