Method and apparatus for determining thickness of an OPC layer o

Details Method and apparatus for determining thickness of an OPC layer o Method and apparatus for determining thickness of an OPC layer o

1995-12-22

1997-04-08

Evans, F. L.

Optics: measuring and testing

By configuration comparison

With photosensitive film or plate

25055928, G01B 1106

Patent

active

056193300

ABSTRACT:
The invention relates to a method for determining the thickness of an OPC layer 24 that is strongly absorptive to light at a first wavelength and substantially transmissive to light at a second wavelength. According to the method, the OPC layer is illuminated with light from an array 34 of fluorescent lamps 36 and the light transmitted through the layer is incident on a first filter 42 that is transmissive to light of the first wavelength. A first light intensity pattern transmitted through the first filter is sensed and stored in a first memory frame. Then OPC layer is illuminated again with light and the light transmitted through the layer is incident on a second filter 44 transmissive to light of the second wavelength. A second light intensity pattern transmitted through the second filter is sensed and stored in a second memory frame. The ratio of the first light intensity pattern and the second light intensity pattern is determined and utilized to calculate the thickness of the layer. An apparatus for practicing the method utilizes a CCD camera 38 as a light sensor which receives the filtered light. A computer 50 divides the first memory frame by the second memory frame to calculate the thickness of the OPC layer. A suitable display 52 provides a contour plot of the thickness of the OPC layer.

REFERENCES:
patent: 3017512 (1962-01-01), Wolbert
patent: 4077723 (1978-03-01), Pirlet
patent: 4120590 (1978-10-01), Bieringer et al.
patent: 4129781 (1978-12-01), Doyle
patent: 4670779 (1987-06-01), Nagano
patent: 5396080 (1995-03-01), Hannotiau et al.
patent: 5440141 (1995-08-01), Horie

Affiliated with

Also associated with

Rating

Method and apparatus for determining thickness of an OPC layer o does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for determining thickness of an OPC layer o, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for determining thickness of an OPC layer o will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2400802