Optics: measuring and testing – By dispersed light spectroscopy – Utilizing a spectrometer
Patent
1981-11-16
1984-07-31
Evans, F. L.
Optics: measuring and testing
By dispersed light spectroscopy
Utilizing a spectrometer
356334, G01J 318
Patent
active
044626886
ABSTRACT:
An Ebert monochromator is modified in a wafer chuck format and adapted to received and sum spectrally tailored light in discrete band widths so that the meter emulates the photographic response of photo resist to light from a high pressure mercury lamp. The monochromator light path is placed between two closely spaced parallel mirrors (spaced apart on the order of 1/8 of an inch). The apparatus includes a circular entrance aperture having a right angle deflecting cone directed to a slit. That slit thereafter emits light to a cylindrical mirror. At the cylindrical mirror, collimated light rebounds to and on a diffraction grating. The light is chromatically classified at the diffraction grating, rebounds to the cylindrical mirror and on reflection passes to a focussing plane. At the focussing plane the particular spectra detected is displayed. Two apparatus are disclosed for tuning the spectral response of the light meter to the spectral response of the photo resist. In one embodiment moveable shutter elements at preselected intervals on either side of the focussing plane in an alternating pattern are located. By placing a photo sensor downstream of the apertures and focal plane, the flow of light through the light meter is integrated and as spectrally tailored closely parallels the response of the photo resist. According to a second and preferred embodiment, a photo diode array is placed at the focussing plane of the monochromator. The diodes are discretely tuned in their response to emulate the response of the photo resist. The output of the light meter in sum emulates the exposure characteristics of the photo resist.
REFERENCES:
patent: 2823577 (1958-02-01), Machler
patent: 3549261 (1970-12-01), Hach
patent: 4193691 (1980-03-01), Fjarlie
patent: 4253765 (1981-03-01), Kato et al.
LandOfFree
Spectrally tailored wafer chuck shaped light meter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Spectrally tailored wafer chuck shaped light meter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spectrally tailored wafer chuck shaped light meter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-183369