System and method for fluid dispense and coverage control
Techniques herein include systems and methods for dispensing liquids on a substrate with real-time coverage control and removal control. Techniques also encompass quality control of dispense systems. Systems and methods enable visual examination of liquids progressing on a surface of a substrate. This includes capturing and/or examining stroboscopic images of movement of a given liquid on a working surface of a substrate, and then generating feedback data for modifying a corresponding dispense. Dispenses can be modified by increasing/decreasing a dispense rate and increasing/decreasing a rotational velocity of a substrate. Feedback can be generated by automated and/or manual analysis of real time progression as well as post-process analysis of collections of images.
1. A method of quality control, the method comprising:
obtaining stroboscopic images of a plurality of substrates, the stroboscopic images showing a first liquid on a working surface of each substrate, the first liquid having been dispensed onto the working surface of each substrate during rotation of each substrate;
identifying a first set of sample stroboscopic images that includes a given stroboscopic image for substrates of the plurality of substrates;
compiling sample stroboscopic images from the first set of sample stroboscopic images into a video; and
displaying the video, the video showing stroboscopic images across the plurality of substrates.
2. The method of claim 1 , wherein the given stroboscopic image for substrates of the plurality of substrates represents a same point in time in processing of respective substrates.
3. The method of claim 1 , further comprising:
identifying deviations in process by visually identifying image changes in the video.
4. The method of claim 1 , further comprising:
adding additional sample stroboscopic images to the video after obtaining the additional sample stroboscopic images.
5. The method of claim 1 , wherein the sample stroboscopic images show photoresist near an edge of respective substrates.
6. The method of claim 1 , wherein the substrates include semiconductor wafers and wherein the first liquid is photoresist.