  UV laser irradiation (lambda = 193 nm), below and above damage thresholds, is
used to both alter and pattern the surface properties of borosilicate slides to
tune and control the contact angle of a water drop over the surface. Large
variation exceeding 25 deg using laser processing alone, spanning across both
sides of the original contact angle of the surface, is reported. An asymmetric
contact angle distribution, giving rise to an analogous ellipsoidal-like drop
caplet, is shown to improve convective self-assembly of silica nanoparticles
into straighter microwires over a spherical caplet.
