Influence of depth dependent profiles on carrier density measurements
Abstract
Carrier density is a frequently examined parameter for silicon material characterisation. Besides the detection of the minority carrier lifetime under low injection conditions like QSSPC, CDI/ILM, and PL more advanced material characterisation methods are based on carrier density measurements. Although spatial resolution has been included in many measurement techniques, the depth dependence of the carrier profiles is typically neglected and homogeneous carrier profiles are assumed. This assumption, however, does not hold for many practical cases and may introduce significant systematic errors. In this work, analytical simulations show the expected errors quantitatively. Iron imaging is taken as an example to demonstrate the magnitude of the systematic error. A correction method is provided which accounts for the inhomogeneous carrier profiles.
