Fabrication of single-mode channel polymer waveguides using vacuum assisted microfluidic soft lithography

We report on the fabrication of single-mode channel waveguide structures produced by the vacuum assisted microfluidic soft lithography technique. The soft lithographic technique in conjunction with a specially designed photomask pattern and a synthesized UV curable epoxy resin can result in a high yield, cost-effective method for fabrication of channel waveguides. In particular, the use of the microfluidic technique allows for the production of freestanding high quality single-mode channel waveguides on various substrates. Notably, the introduction of sectional flow tapers allows for proper uniform filling of long length small cross-sectional waveguide structures that would ordinarily succumb to clogging at shorter distances during channel filling. The fabricated polymer waveguide was 30 mm in length with a cross section dimension of 7 × 7 μm. The single-mode waveguide propagation was confirmed with beam profiler measurement, and the measured propagation loss for this polymer waveguide was about 0.55 dB/cm.