Modulated photoluminescence studies for lifetime determination in amorphous-silicon passivated crystalline-silicon wafers

A simple, inexpensive method for characterization and quality control of silicon wafers and wafer coatings is proposed, based on the measurement of the complex frequency response of the photoluminescence signal to a sinusoidal excitation, which we term modulated photoluminescence. The minority carrier lifetime may be extracted directly from the phase information without the need for difficult and often imprecise intensity calibrations. We apply modulated photoluminescence measurements to study the influence of interface defects on the recombination of excess carriers in crystalline silicon wafers with different passivation schemes.