Patent ID: 8364428
Filing Date: 2013-01-29
Classification: G01R

Abstract:
1. A junction-photovoltage method of contactlessly determining a physical parameter of a semiconductor structure comprising at least one p-n junction located at a surface, comprising: a) illuminating the surface with the p-n junction of the semiconductor structure with a light beam of a first wavelength to create excess carriers at the surface; b) modulating the light intensity of the light beam at a single predefined frequency; c) contactlessly determining a first photo-voltage at a first position inside the illuminated area and contactlessly determining a second photo-voltage at a second position outside the illuminated area; d) contactlessly determining a third and a fourth photo-voltage by illuminating the surface with the p-n junction by a light beam having another wavelength and repeating the process b) and/or by selecting further measurements positions outside the illumination area; and e) calculating a physical parameter of the semiconductor structure based on the first, the second, the third, and the fourth photo-voltage.