A computer-controlled deep-level transient spectroscopy system for semiconductor process control

A flexible minicomputer-based automated Deep Level Transient Spectroscopy (DLTS) system for routine process control is described. All critical instrument parameters including sampling aperture locations, temperature, and excitation pulse frequency, width, and amplitude are controlled and can be varied automatically by the interactive software program. Critical trap parameters, such as trap density, capture cross section, activation energy, field-dependent effects, and trap profile may be simultaneously measured during one thermal scan. Considerable reduction in acquisition and analysis time compared to DLTS systems requiring multiple thermal scans has been demonstrated.