SBIR Phase II: Novel Sensor for Control of Cleaning Processes During the Fabrication of Microstructures

This Small Business Innovation Research (SBIR) Phase II project provides a unique and robust in-situ sensor for detection and control of impurities in microstructures and porous layers associated with manufacturing of semiconductor, MEMS, and emerging nanodevices. Use of impedance as a measure of contamination in bulk fluids is well established. However, applying it in micro-scale features is novel and has many promising applications. The proposed Electro-Chemical Residue Sensor (ECSR) technology is not aimed at developing yet another sensor to measure contaminants in fluids. It is rather aimed at the in-situ, real-time, and low-cost measurement of residual contamination inside and on the sidewalls of micro- and nano- features (the bottlenecks of cleaning, rinsing, and drying). The Phase II proposed plan is to design, fabricate, and test a prototype sensor assembly and develop its interface with process tools for cleaning, rinsing, and drying of micro-features. The first planned application, amounting to annual commercial market revenue of $9M to $30M, will be in rinsing and drying of patterned wafers and porous films in micro-electronics manufacturing. Currently, these operations are often run with no adequate real-time control. Insufficient cleaning and drying have significant negative impact on manufacturing yields and device performance. On the other hand, excessive cleaning and drying results in damage to the micro-structures, increase in cost, and wasting of chemicals, water, and energy. The application of the ECRS technology to wafer rinsing alone is expected to reduce water usage by 40-60%.