MultilayerMicrofluidicsI. Introductiona. Goal i. To make a simplified packaging of a multi-layer microfluidics for fluid flow.ii. How to create a multilevel microfluidics system?iii. How to control fluidic flows in this system?b. Background information c. Our preliminary findings include many research groups. One of the more important groups our group referred to was part of the University of California, Berkeley.d. Initial ideai. Channels - some preliminary design ideas about controllable/passive microfluidic, active control at channel junctions, and fabrication methods (surface, bulk, bonding, etc.).ii. Controls of fluids – using a bubble actuator and check valves for fluid flow.II. Project Process Overviewa. Gathering all the information from different research groups related to microfluidics and integrating the ideas to develop a multi-layer system.b. Division into many groups to research on materials, devices, circuits/networks, and research groups related to biomems.c. After the preliminary research is done we broke up into:i. Microchannel group – designing the multi-layer channels and design of the masks involved.ii. Controls group – designing of the controls system to integrate into the design of the multi-layer channel system.iii. Experimental group – becoming familiar with the machinery we will be using.iv. Development team – organize assignments and budget time.d. Initial design is modified to fit Theresa's packaging due to time and budgetconstraints and desire to actually fabricate devicesi. Increased channel width from 150um to 250 um for ease of manufacturing and leak prevention.ii. Increased interconnect size to 500um X 500um to make alignment of initial devices easier.iii. Mask design templates (i.e. overhead transparencies) will be made so we can explore variations of the mask design.iv. 3-Dimensional modeling will be assisted with the use of golf tees and rubber bands.v. Problems – geometry of the channels and junctions.1. Fabrication process - masking2. Actuation – electrical or pressurized3. Geometry of junction4. Materials to be used – PDMS, PMMA, Su8, Pyrex, and/or Silicone. Proposed controlled valve design using a fluid controlled thin PDMS layer. f. Final channel design formulationi. Ground rules for design and future design have been set.ii. First mask design has been developed.iii. Two mold design:distinct top and bottom layer.iv. Channels dimensions (0.5 mm and interconnects are 1 X 1mm)v. Test sites include: top & bottom, up & 2 outs, bottom, down, and top.g. Final controls design formationi. Active valves to control fluid flow.ii. Gas lines to control fluid flow instead of piezoelectric control of fluid flow. (Budget and Time restrains)III. The Final Device Designa. Channel layoutb. Controls integrationc. Fabrication processi. Spin coating and patterningii. Liftoff of pdms, etc..d. Packaginge. Device functionalityIV. Detailed Material Information in Final Devicea. Substratesb. PDMS, Su-8c. Liquid/channel interface interactiond. Gas/channel interface interactionV. Results of device testinga. Early device test results and discussionb. Final device test results and discussionVI. Future work and possible ideas for alternative
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