フェムト秒レーザーを用いたポンプープローブ法による化合物半導体の欠陥分布計測

抄録

Transient reflectivity measurements following ultrafast laser excitation reveal that the decay time of photoexcited carriers in semiconductor materials decreases as defect density increases due to recombination through deep impurity levels. We demonstrated microscopic imaging of defect density distributions for compound semiconductors (semi-insulator GaAs, epitaxially lateral overgrown In GaP, and GaN) with high sensitivity by plotting reflectivity at a fixed time after the pump pulse, which corresponds to carrier lifetime.