Traps and the kink effect in AlSb/InAs HEMTs

The characteristics of AlSb/InAs/GaAs HEMTs with and without a kink in the output characteristics are compared. By measuring the output resistance dispersion in the frequency range from 10 Hz to 100 KHz the relationship to trapping phenomena were studied. Significant differences in kink behavior were found between material grown in different MBE systems. The light sensitivity and gate length effects were also examined. It appears that devices without kink have an additional trapping level in the AlSb which partially compensates the original mechanism causing the kink.