Precise temperature control of microfluidic chamber for gas and liquid phase reactions

A silicon-based micromachined fluidic chamber with integrated platinum heaters and sensors has been developed and thermally well characterized. This device is highly applicable to both gas and liquid phase reactions that require excellent thermal control. The chamber is thermally isolated from the bulk silicon by a thin silicon nitride membrane resulting in low power consumption. The digitally feedback controlled device demonstrates the ability of precise temperature control, excellent temperature uniformity, rapid heating and cooling. These thermal characteristics are ascribable to the success of miniaturized reaction chamber and Micro Total Analysis Systems (mu TAS). In addition, gain scheduling control algorithm in conjunction with normal feedback proportional and integral (PI) scheme was implemented to provide better thermal cycling performance. 3D numerical simulation was also conducted to map the spatial temperature distribution within the miniaturized fluidic device. Simulation results and experimental data show good agreements. (C) 2000 Elsevier Science S.A. All rights reserved.