Microfluidics materials are of various types and application-specific. PDMS is one of the most preferred and cost-effective solutions for research and low-volume manufacturing. After having the mold, PDMS replicas are generated by a technique called soft-lithography. This protocol describes the preparation of PDMS microchannels using SU8 molds, 3D Printed resin molds, and/or metal molds by the soft lithography technique, SLA printing, or CNC machining.
Microfluidics materials are of various types and application-specific. PDMS is one of the most preferred and cost-effective solutions for research and low-volume manufacturing. After having the mold, PDMS replicas are generated by a technique called soft-lithography. This protocol describes the preparation of PDMS microchannels using SU8 molds, 3D Printed resin molds, and/or metal molds by the soft lithography technique, SLA printing, or CNC machining.
Manufacturing of Y-branch coupler depends on high technology production equipment and in-factory accuracy assembly tools. The manufacturing of a 1×2 Y-branch symmetric and asymmetric waveguide coupler based on the mould replication process and Epoxy OG142 as an optical core is presented; an alternative to provide a less complex technique. The polymer optical waveguide adopted two basic designs: the 1×2 Y-branch symmetric coupler as the core structure and the 1×2 asymmetric coupler that allows non-symmetric optical splitting. This paper focused on the main structure fabrication of the 1×2 symmetric and asymmetric waveguide coupler that produces a power output. The fabrication was done by engraving acrylic to produce a master mould using CNC machining tools for optical devices. Both 1×2 devices were made via soft lithography, which duplicated the pattern from the master mould onto a second mould to produce an actual device. Optical polymer epoxy OG142 was injected into the second mould, of which the product was then put on top of acrylic. The device was completed after curing the optical polymer glue, epoxy OG142, by exposing the assembly on the second mould under UV light until both parts bonded. The difference between the simulation and design TOFR value was only ±2%. This showed that the simulation and design are in good agreement, which provides similar performance.
This paper presents a novel latchable phase-change actuator that can potentially be used for flow valving and gating in portable lab-on-a-chip systems, where minimal energy consumption is required. The actuator exploits a low melting-point paraffin wax, whose solid-liquid phase changes allow the closing and opening of fluid flow through deformable microchannels. Flow switching is initiated by melting of paraffin, with an additional pneumatic pressure required for flow switching from open to closed state. After paraffin solidifies the switched state is subsequently maintained passively without further consumption of energy. The actuator can be fabricated from PDMS through the multilayer soft lithography technique. Testing results demonstrate that the actuator has a response time about 60-100 sec for flow switching, and can passively hold a microvalve closed under pressures up to 35 kPa.
Manufacturing of Polymer-based 1×2 Y-branch Symmetric and Asymmetric Waveguide Coupler through Moulding Technique