Nanometer-scale characterization of lateral p–nq junction by scanning capacitance microscope

Spatial variation of the local capacitance of a lateral p–nq junction is measured at various sample biases by our home-made Scanning Capacitance Microscope SCaM.rAtomic Force Microscope AFM.which facilitates direct measure- ments of capacitance itself. Local Capacitance–Voltage C–V.characteristics are measured at the same time during scanning of the cantilever. It is found that the p-nq junction boundary as measured by the SCaM moves toward the p-region at negative bias, and to the opposite direction at positive bias. The local C–V characteristics at around the boundary in the p-region show a low-frequency C–V curve, which in the nq-region or just at the boundary, high-frequency C–V curve. These ‘‘unusual’’ phenomena are well interpreted with the help of a device simulator like ‘‘VENUS-2DrB’’. q2000 Elsevier Science B.V. All rights reserved.