Uncertainty in Photoconductance Measurements of the Emitter Saturation Current

We determine uncertainty in photoconductance (PC) measurements of the emitter saturation current density (J_0e). A Monte Carlo method is used to calculate the impact of uncertainty from the input parameters including the test equipment calibration, the intrinsic-recombination model, and the measured sample´s thickness, doping, and optics. The uncertainty in the measurement of J_0e is calculated, where we find that the sensitivity to input uncertainty depends on the measurement mode, transient decay, or quasi-steady-state PC. For quasi-steady-state measurements, the uncertainty in J_0e is largely affected by thickness and generation uncertainty. For transient measurements, thickness uncertainty dominates the uncertainty in J_0e. The wafer doping and measured voltage data has little impact on the resultant J_0e uncertainty. We find, in our case study, that measurements of J_0e to be accurate within 3%-6% when using the transient mode, and 4%-7% using the quasi-steady-state mode.