14th International Conference on Nuclear Microprobe Technology and Applications

Fabrication of Three-dimensional SU-8 Microchannels by Proton Beam Writing for Microfluidics applications: Fluid Flow Characterisation

10 Jul 2014, 11:50

20m

Auditorium (Centro Culturale San Gaetano, Padova)

Oral Communication Session 7 - 5th Proton Beam Writing Workshop

Speaker

Mr Saad Alshehri (University of Surrey Ion Beam Centre, Advanced Technology Institute, U.K.)

Description

The proton beam writing (PBW) technique has significant advantages over other lithography techniques in the fabrication of three-dimensional structures with a high aspect ratio, straight and smooth sidewalls. These features potentially facilitate the rapid prototyping of microfluidic systems with some crucial improvements in the quality. A network of polymeric buried channels was fabricated in SU-8 as a part of project to develop functional microfluidic networks. Using protons with energies between 2.5 MeV and 0.75 MeV buried channels have been fabricated with minimum feature size of around 1 µm and depths of 40 µm and their properties have been evaluated. Straight-walled channels with surface roughness of around 2nm for the sidewalls of the channels were measured. The exposure regime, post processing and examples of functional networks fabricated using PBW are described. In addition, the paper will present theoretical modelling using COMSOL multiphysics developed to predict the flow pattern properties of fluid in the SU-8 microchannels structured by PBW. This modelling focused on the investigation of the impact on the functionality of microfluidics system of enhancements in the microchannel texture and structural engineering. The results are compared with some microchannels in literature fabricated by conventional lithography techniques.