A METHOD FOR DETERMINING CHARGED ENERGY STATES OF SEMICONDUCTOR OR INSULATOR MATERIALS BY USING DEEP LEVEL TRANSIENT SPECTROSCOPY, AND AN APPARATUS FOR CARRYING OUT THE METHOD

摘要

A method for determining charged energy states of semiconductor or insulator materials by using deep level transient spectroscopy, and an apparatus for carrying out the method, comprising the steps of exciting said sample by the application of periodical exciting pulses (Pg) to change the initial charge state thereof, detecting the transient response of said sample when it returns to the thermodynamical balance condition following the termination each of said excitation pulses, blocking said detection during a blocking period (TT) defined as the combined existence of said exciting pulses (Pg) and of a dead period (TH) including the recovery period of the means used for the detection, performing a weighted integration operation on a detected response signal (SR) by the application of a symmetrical square ware synchronizing pulse (PL) as a weighting function synchronized to the frequency of said exciting pulses (Pg), blocking said detection in each of said detecting periods for the duration of a further blocking period (TT) which begins in a moment (t4 or t10) defined between the starting moments of the two exciting pulses (Pg) immediately preceding and following said detecting period, and synchronizing said synchronizing pulses (PL) to terminating moments (t3, t6, t9) of said dead periods (TH) to have a period time (2TP) which is equal to the period time of said periodical in exciting pulses (Pg).