DEEP-LEVEL TRANSIENT SPECTROSCOPY STUDY OF HOLE TRAPS IN P-TYPE CDTE

The presence of hole traps in p-type CdTe has been studied by deep-lev el transient spectroscopy. Two hole traps labelled H1 and H2 with acti vation enthalpies of 0.26 eV and 0.61 eV have been detected. Both trap s act as donor point detects with entropies of 2.4 x 10(-4) eV K-1 for H1 and 8.5 x 10(-4) eV K-1 for H2. The capture cross-sections are fou nd to be temperature independent sigma(pH1) congruent-to 3 x 10(-18) c m2 and sigma(pH2) congruent-to 1.2 x 10(-17) cm2. The concentration of detects H1 has its maximum (equal to about 1 x 10(13) cm-3) close to the surface whereas the defects H2 seem to be located at around 0.5 mu m distance from the surface (with a concentration of 2 x 10(12) cm-3).