Monitoring and Manipulating Etching in Real-Time
Fabricating the assorted chips of a computer is a very complicated process in part because it is almost trial and error at first. The only way to know if the mask, which controls the etching, is going to work for mass production is to make some dummy wafers to test it, and if there is a problem, a new mask has to be made. Researchers at the University of Illinois at Urbana-Champaign, with support from NSF, have a new technique that allows one to watch the etching process in real-time, and change the pattern being etched while the etching is occurring.
To monitor the etching the researchers bounced lasers off of the material and measured for interference. Where the semiconductor has been etched into its height will be different, and different heights interfere with the light differently. With this nanoscale monitoring, the researchers are able to watch the etching process and identify where any trouble spots are. To give them the ability to correct these issues on the fly, the researchers used a projection system instead of a glass mask.
Together these advances could cut costs in the semiconductor industry as fewer and cheaper trials will be needed to test a design for a new component. However this technology is not limited to semiconductors and the researchers hope it can be used to monitor other processes, like those associated with the growth of nanotubes.