NSF Award
9860514
9860514<br/> This Small Business Innovation Research Project will develop an in-situ, real-time process control tool for micro-electric-mechanical system (MEMS) deep-etch fabrication. Deep etch processes are used to manufacture high aspect ratio structures up to several hundred microns thick, which would be difficult or impossible to produce by other methods. Deep-etch and other MEMS technologies promise<br/>to deliver new devices with increased performance and functionality at lower cost. A major difficulty in deep-etch technology is the control of the etch depth during the etching process. Currently etch depth is measured post-etch using ex-situ destructive scanning electron microscopy. This is extremely inefficient, and is a major hurdle to be surmounted before extensive production takes place. Preliminary measurements at On-Line Technologies have demonstrated that it is possible to monitor the etch depth through the analysis of the infrared reflectance spectrum. In Phase I, an etch depth sensor will be constructed incorporating a Fourier transform infrared based reflectometer and analysis algorithms. The sensor will be integrated onto a deep-etch tool for in-situ testing, and data will be collected and analyzed in real-time during the etch process. <br/> The specific anticipated results of the use of the proposed metrology are: (1) to reduce cost through the reduction of destructive measurements and the improvement in process control; (2) to increase the reproducibility of the MEMS structures through better process control; and (3) to provide useful feed-back for process development, thus reducing development time. These results will have a great impact on the deep-etch MEMS market, as they will help future MEMS applications to mature and come to market at a faster pace through cheaper characterization and improved process control.
