An apparatus and method for electrostatic spray deposition of small
targets, such as medical devices, like stents. The apparatus includes a
target holder that applies a first electrical potential to the target,
and an electrostatic dispensing nozzle that applies a second potential
sufficient to attract the coating fluid from the nozzle toward the
target. Because the entire dispensing nozzle is conductive, the coating
fluid may receive a greater charge than may be obtained with internal
electrode-type nozzles. Electrostatic attraction of the coating fluid to
the target is enhanced by the combination of higher charge density
imparted to the coating fluid by the conductive nozzle, and application
of a momentary voltage spike to the target to provide consistent
conductivity between the target and its holder, thereby ensuring the
target is presented with the full first potential applied to the holder.
The voltage spike may also be used independently of the conductive
nozzle.