FIELD: nondestructive testing. SUBSTANCE: semiconductor sample is cooled up to helium temperatures, is subjected to influence of permanent magnetic field with induction B and to SHF radiation directed perpendicular to investigated surface of sample and in parallel to induction vector 
of permanent magnetic field which frequency is selected smaller than frequency of collision of carriers with atoms. In addition sample is subjected to action of variable magnetic field with amplitude b much smaller than B which changes with audio frequency directed perpendicular to surface of investigated layer of sample and in parallel to permanent magnetic field. Value of change of intensity of SHF signal reflected from sample depends on value of permanent magnetic field which is determined by concentration of charge carriers by calculation. EFFECT: enhanced sensitivity and capability of check in thin layers of degenerated semiconductors. 2 dwg
