METHOD AND DEVICE FOR DETECTION OF PHYSICAL CHARACTERISTICS OF SEMICONDUCTOR PLATE Russian patent published in 1997 - IPC

FIELD: semiconductor instruments, manufacturing of integral circuits. SUBSTANCE: method involves illumination of local region on plate surface with modulated monochromatic light in different wavelength, measuring photo electromotive force, selection of flows from linear pieces of photo electromotive force dependency on wavelength and measurement of said flows, illumination of symmetric region on opposite side of plate with modulated monochromatic light in different wavelength, measuring photo electromotive force on this side, selection of flows from linear pieces of photo electromotive force dependency on wavelength, so that ratios of flows for each wavelength are equal, and measurement of said flows. Resulted values are calculated using all measurements and taking into account plate thickness and absorption factors. Corresponding device has stage with hole, monochromatic light source which is tuned in wavelength and modulated in intensity. In addition device has two optical elements for generation of light beam which is limited in space. Said elements are located on opposite sides of stage and are optically connected by means of optical systems of light transmission and optical commutator. In addition device has photo electromotive force detector which has capacitance electrode which is located between one optical element and stage plane. In addition device has photodetector which is connected to light sources, and control recording unit which input is connected to photo electromotive force detector; output of control unit is connected to light sources. EFFECT: optimal manufacturing process. 30 cl, 2 dwg