An Open Circuit Voltage Decay System for a Flexible Method for Characterization of Carriers’ Lifetime in Semiconductor

Among all the material parameters of a semiconductor, the lifetime of the carriers is one of the most complex, as it is a function of the dominant recombination mechanism, the number of carriers, the structural parameters and the temperature. Nevertheless, the lifetime of the carriers is a very useful and fundamental parameter to be determined for the qualification of the semiconductor in order to allow the improvement of the manufacturing process and the optimization of the operation of the semiconductor device. Thus being strongly linked to many physical and electronic parameters, the lifetime of the carriers cannot be provided only with a theoretical average value and an experimental measured value must be obtained. In the case of semiconductor junctions, precise measurements of the open-circuit voltage decay, OCVD, make it possible to trace the lifetime of the carriers through the device. An automated method for OCVD measurements presented in this contribution overcomes the main limitations that arise in the standard method when used for the characterization of the lifetime of carriers as it achieves the "open circuit conditions" of the device under test and reduces inherent noise of the differential operation mode of the method.