Bruzewicz et al. [4] used a modified plotter to create a barrier
pattern by printing polydimethylsiloxane (PDMS) onto paper. This
method overcame the problem of physical inflexibility of devices
made using photolithography. However, the quality of the barrier
definition deteriorated, since the penetration of PDMS in paper
could not be very well controlled, resulting in the wall of the barrier
not being straight. This method is also limited to producing devices
on an up-graded scale and at a high speed