Wafer bath imaging
AssigneeTokyo Electron Limited
InventorsJoel Estrella, Ihsan Simms, Michael Carcasi, Joshua Hooge, Hiroshi Marumoto
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Abstract
An exemplary method of monitoring a bath process includes processing a first wafer by submerging the first wafer within a bath solution; capturing a video of the bath solution containing the first wafer during a first time interval; analyzing the video based on intensity of light captured in a frame of the video; and based on analyzing the video, determining a first metric of the bath solution during the first time interval.
Claims20
A method of detecting wafer bridging, the method comprising:
- submerging a plurality of wafers within a bath solution;
- illuminating a side of the plurality of wafers with a light source;
- capturing a first image of a first portion of the side of the plurality of wafers;
- and
- determining wafer bridging occurred between any one of the plurality of wafers based on the first image.
A method of detecting wafer bridging, the method comprising:
- submerging a plurality of wafers within a bath solution;
- illuminating a side of the plurality of wafers with a light source;
- capturing a video of a first portion of the side of the plurality of wafers, the video comprising a plurality of frames;
- analyzing the video by:
- dividing at least one frame of the video into a one dimensional array of regions normal to the plurality of wafers, each region comprising a column of pixels;
- calculating a mean pixel value across the one dimensional array of regions to identify positions of the plurality of wafers based on pixel value variations;
- and
- determining distances between adjacent ones of the plurality of wafers based on the identified positions;
- and
- determining wafer bridging occurred between any one of the plurality of wafers when any of the determined distances is less than a threshold distance.
A method of detecting wafer bridging, the method comprising:
- submerging a plurality of wafers within a bath solution;
- illuminating a side of the plurality of wafers with a light source;
- capturing a first image of a first portion of the side of the plurality of wafers;
- analyzing the first image to count a number of wafers in the plurality of wafers based on pixel peaks in the first image;
- and
- determining wafer bridging occurred between any one of the plurality of wafers when the counted number of wafers is less than an actual number of wafers in the plurality of wafers.
Dependencies are inferred from the claim text.