Patent ID: 6388454
Filing Date: 2002-05-14
Classification: G01R

Abstract:
An electro-optic sampling prober comprising:a laser for radiating laser beams based on a control signal; an electro-optical element which is placed in contact with wiring of an IC wafer which is a measured subject, wherein an electric field caused by a measured signal applied to the wiring of the IC wafer is applied to the electro-optical element to be changed in optical characteristic; an optical module which is configured using polarization beam splitters, wavelength plates and photodiodes, wherein the optical module isolates reflected beams, which are produced by reflection of the laser beams transmitting through the electro-optical element by a surface of the electro-optical element placed opposite to the wiring of the IC wafer, so that the optical module converts the reflected beams to electric signals; a lamp for illuminating the IC wafer with illumination light; a prober unit for enclosing an optical path along which the laser beams propagate and an optical path along which the illumination light propagate; an infrared camera for producing an image of the IC wafer which is illuminated by the lamp; a dichroic mirror for separating the laser beams from the illumination light; an optical wavelength filter which is arranged on an optical path connected between the dichroic mirror and the photodiode; and wherein the optical wavelength filter is attached to installation/removal members, by which the optical module is fixed to the prober unit.