Effects of contact-stress on hot-embossed PMMA microchannel wall profile

Hot-embossing (thermal-compression) based microchannel fabrication techniques have gained much attention recently due to their low-cost setup and ease of implementation. However, not much effects have been attempted in trying to understand or characterize the mechanics of the hot-embossing process in fabricating microchannels. Most research groups still rely on trial-and-error processes to hot-emboss microchannels for microfluidic control applications. The present paper describes the application of the contact-stress analysis to understand the mechanism of using molds with micro-features to hot-emboss PMMA substrates. Experimental results showing that the resulting microchannel wall profile can be predicted with good accuracy via a close-form solution of the analysis are also presented.