This paper discusses on a low-cost technology for the fabrication of microfluidic devices on glass substrate using metal embossing technique. The fabrication technique demonstrated is a much simpler approach of embossing on glass using thermo-compression process with patterned metal layer to define device structure. Well established Printed Circuit Board (PCB) fabrication photo-process is used to realize desired planar geometry on metal layer deposited over a glass substrate. The depth of the channel is defined by the thickness of the metal which is deposited by electro-plating. The embossing technology offers a relatively safer approach conducive to batch processing to enable repeatable, high-yield low-cost devices fabricated using low-cost equipment. Major challenges of achieving adhesion of deposited thick Nickel layer without peel-off and control of the thermo compression process to achieve reliable and repeatable embossing without structural distortions were addressed. To prove its suitability for manufacturing, experiments were carried out with full wafer of 6” x 6” square glass wafer and optimal process steps for low-cost Micro-fluidic device manufacturing have been well established.

Fabrication of Microfluidic devices have gained popularity in a wide range of application demanding fluid flow control such as Anti-microbial resistance, Integrated blood test systems, drug delivery system, protein separation, DNA extraction, in-vitro diagnostic studies, lab-on-a-chip, organ-on-a-chip, inkjet printers and other industrial sensors. Fluid flow regulation, on/off switching and sealing of fluids can be achieved by incorporating Microvalves. The shape of the microvalve plays a key role in desired actuation of the microvalves. Therefore, a detailed study of various structures of the microvalve is crucial. This work discusses about the stability and reliability of different microvalve shapes. Simulation work gives a comparative study showcasing the displacement of the microvalve thin film polymer layer on account of applied pressure on several shapes of same area. Furthermore, details of stress distribution for the same has been carried out. The analysis focusses on the circular, elliptical and capsule shapes of the microvalve. The comparative study of the simulation results revealed that the maximum stress experienced by the microvalves of circular shape is 1.1 times lower than that of elliptical shape. While, circular shape microvalve shows 1.22 times lower stress when compared to capsule shape. In addition, displacement of the circular shape microvalve is 1.33 and 1.31 times greater than elliptical and capsule shapes for the same area and applied pressure respectively. The study manifests that the circular shape microvalve performance indicate better stable actuation when compared to the rest of the shapes. Microfabrication of the same is carried out using dry film photoresist which is highly cost effective.