An understanding of the defects intentionally or unintentionally introduced in semiconductor crystals by crystal growth or device fabrication procedures or by operation in nuclear and space radiation environments is essential to insure proper performance of electronic and optoelectronic systems. The use of diode capacitance measurement techniques for the study of deep defect levels in semiconductors is discussed, including a recently developed technique based on transient capacitance effects. The theoretical and experimental details of this new technique, involving the use of a lock-in amplifier to process capacitance transients, are presented in appendices. This technique is applied to Schottky barrier and asymmetrical p-n junction diodes of gallium arsenide and silicon, which are primary materials of interest in a variety of device applications. Co60-gamma ray and electron irradiations on unimplanted material produce levels that are similar to some found in the complex defect spectra of ion-damaged samples.

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An understanding of the defects intentionally or unintentionally introduced in semiconductor crystals by crystal growth or device fabrication procedures or by operation in nuclear and space radiation environments is essential to insure proper performance of electronic and optoelectronic systems. The use of diode capacitance measurement techniques for the study of deep defect levels in semiconductors is discussed, including a recently developed technique based on transient capacitance effects. The theoretical and experimental details of this new technique, involving the use of a lock-in amplifier to process capacitance transients, are presented in appendices. This technique is applied to Schottky barrier and asymmetrical p-n junction diodes of gallium arsenide and silicon, which are primary materials of interest in a variety of device applications. Co60-gamma ray and electron irradiations on unimplanted material produce levels that are similar to some found in the complex defect spectra of ion-damaged samples.