Patent ID: 6529018
Filing Date: 2003-03-04
Classification: G01N

Abstract:
A method of detecting a gate defect in a silicon chip comprising a polysilicon gated field effect transistor in a semiconductor device wherein said defect causes the generating and emitting of radiation in the visible and near infrared portions of the spectrum responsive to stimulation by incident light, comprising the steps of:a. providing the semiconductor device with a photodiode electron-generating region comprises a diffused region of the silicon chip to be used as a circuit stimulus in response to said incident light; b. illuminating the photodiode region of the semiconductor device with incident light at a first wavelength to stimulate the photodiode region of said semiconductor device; c. detecting light emitted from polysilicon gate areas of the silicon chip at a second wavelength at a further location of said semiconductor device responsive to the detection of a defect in said silicon chip at said location remote from the illuminated region, providing the silicon chip with conductive paths connecting the photodiode electron-generating region to terminals of the polysilicon gate areas; and d. filtering light emitted at the second wavelength by the defect at said location of the semiconductor device to eliminate therefrom light emitted at the first wavelength.