SBIR Phase I: Development of Particulate Mass and Count Monitoring Instruments Using Micro-Electro-Mechanical Resonant Balances

点击翻译按钮获取中文摘要

This Small Business Innovation Research Phase I project aims to develop low-cost light-weight miniaturized instruments, based on micro-electro-mechanical resonant nanobalances, for real-time monitoring of concentration, and size distribution of airborne micro/nano-particles. Aerosol particles in the diameter range from nanometers to microns play important roles in air quality, human health, visibility in the atmosphere, the radiation balance of the earth (climate change), and stratospheric ozone depletion. Aerosol contaminants in industrial cleanrooms can limit the size and quality of integrated circuit elements. There has not been enough progress in light weight and low-cost aerosol particle monitoring technologies over the past decades and the existing technologies cannot address all the existing needs (e.g. in semiconductor industry). The innovative approach proposed here integrates micro/nanoscale electromechanical resonant balances within miniaturized micro-orifice cascade impactors. Cascade impactors separate particles in the air flow based on their size and deposit them on designated micro/nanoscale electromechanical resonant mass balances performing real time mass measurement. The proposed instrument can sample the surrounding air, separate airborne particles into several size ranges, and measure the individual and/or cumulative mass of particles in each size range.The broader impact/commercial potential of this project is development of a more capable and cost effective category of airborne particulate monitors. Currently available particulate monitoring systems can be divided into two major categories: 1. Laser-based counters, and 2. Inertial impactors. Other than being relatively costly and bulky and their need for frequent calibration, lower cost laser-based counters can only detect particles with diameters as small as 0.3µm. Inertial impactors on the other hand can collect particles with diameters as small as a few nanometers, but such systems generally offer no automated or real time processing capability. Collected particulate matter in such systems is manually weighed after sampling a large enough volume of air. Successful development of the proposed technology allows real time monitoring of nanoscale airborne particles down to a few nanometers size range using low cost, light weight instruments. The target market for the proposed instruments can be divided into two major sections: a) Cleanroom/controlled environment monitoring. This includes semiconductor/micro-manufacturing and pharmaceutical cleanrooms, operating rooms, etc.; b) Personal particulate mass exposure monitors for work place safety in industrial environments prone to excessive micro/nanoparticulate generation and dispersion. This includes Nanomaterials processing plants, mines (e.g. coal mines), metal processing plants, etc.