Patent ID: 7414409
Filing Date: 2008-08-19
Classification: G01R

Abstract:
1. A non-contact apparatus for measuring p-n junction leakage current comprising: means for illuminating the area of a semiconductor structure with an intensity modulated light, controlled by a computer, means for detecting and measurement of the JPV signal inside the illumination area and optically coupled to the illuminating means, and connected to the computer, means for monitoring and adjustment of the air gap between the p-n junction and probe electrodes controlled by the computer, means for calibration of surface reflectivity on various test wafers, an optical system installed in the vicinity of, or directly above, the illumination means and detecting the JPV signal from the tested p-n structure, the optical system being designed for pattern recognition and placing the illumination means and the means for detecting the JPV signal in the vicinity of tested p-n junction, the optical system, including an objective lens and a CCD matrix, connected to the computer, and means for wafer positioning, using the leakage measurement in different test p-n junctions, including one or more linear stages and or a rotary stage, the stages being controlled by the computer.