FIELD: physics.
SUBSTANCE: method is meant for use during outgoing and incoming quality control of semiconductor diodes and evaluating their temperature reserves. Heating current pulses with constant amplitude are transmitted to the analysed diode. Initial direct current is transmitted in the time intervals between the pulses of the heating current. The value Q-1, which is the inverse of the pulse ratio of the heating current is measured using a harmonic law with initial frequency Ω. At frequency Ω, amplitude of variation of the heating power Pm1(Ω) is measured, as well as amplitude of the temperature-sensitive parametre 
in the intervals between pulses of the heating current and phase shift between them is determined. Modulus of thermal impedance of the diode is determined using formula 
where Kt is the temperature coefficient of foward voltage of the diode during flow of the initial direct current. Impedance phase is equal to the phase shift between the temperature-sensitive parametre and the first harmonic.
EFFECT: more accurate measurement of thermal impedance of semiconductor diodes.
2 dwg
