Patent ID: 7521954
Filing Date: 2009-04-21
Classification: G01R

Abstract:
1. A method of determining a diffusion length of a minority carrier in a material, comprising: applying a first excitation light having a first photon flux and a first wavelength to a material; measuring a first surface photo voltage resulting from the application of the first excitation light; applying a second excitation light having a second photon flux and the first wavelength to the material; measuring a second surface photo voltage resulting from the application of the second excitation light; applying a third excitation light having a third photon flux and a second wavelength to the material, a ratio of the third photon flux to the first photon flux being a known value; measuring a third surface photo voltage resulting from the application of the third excitation light; and determining a diffusion length of a minority carrier in the material based on the measured first, second and third surface photo voltages.