METHOD AND DEVICE FOR DETERMINING DIFFUSION LENGTH OF CHARGE CARRIERS IN SEMICONDUCTOR PLATES Russian patent published in 2016 - IPC H01L21/66 

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment and is intended for contactless nondestructive determination of the diffusion length of charge carriers in semiconductor plates, including coated with a transparent dielectric layer. Method of measuring diffusion length of charge carriers in semiconductor plates involves measuring a signal proportional to concentration of nonequilibrium charge carriers, arising in the point of testing of the semiconductor plate by their diffusion of generation, created at different distances from the point of testing due to formation in these areas of the light spots of small surface area of radiation spectral range of internal photo effect in a semiconductor, constructing an experimental dependence of amplitude of the measured signal from the distance between the light spot and the point of testing, comparison of test subject to similar relationships calculated theoretically. note here that for taking measurements without establishing electric contact with the analysed plate signal proportional to concentration of nonequilibrium charge carriers in the point of testing, is obtained by passing through the plate of infrared radiation with wavelength from the transparency of the analysed semiconductor and measuring intensity of radiation passed through the plate. Also a device for measuring diffusion length of charge carriers in semiconductor plates.

EFFECT: invention provides the possibility to measure length of diffusion of charge carriers in semiconductor plates without establishing electric contact with the sample directly in areas where will be manufactured devices, as well as in the plates coated with a layer of transparent dielectric.

2 cl, 1 dwg