Application of laser scan lithography to fabrication of microcylindrical parts

Laser scan lithography on fine cylindrical specimens is investigated, and various microparts are fabricated successfully by etching the specimens masked by resist patterns. First, the uniform coating of resist films on fine cylindrical specimens is investigated, and a new method is developed. In the new method, the specimen is dipped vertically in the resist bottle, and the bottle is moved downward. Although the coating thickness of PMER P AR-900 varies from 1.5 to 28 mum depending on the material and the specimen diameter, it is controllable by adjusting the moving speed of the bottle. Next, a test exposure system is manufactured for patterning on a cylindrical specimen. A blue laser light with a wavelength of 473 nm is condensed into a diameter of 6-43 mum on the specimen, and the beam spot is relatively scanned by moving and rotating the specimen. Exposed pattern widths are controlled by changing the scan speeds. Finally, metal specimens with resist patterns are wet-etched in ferric chloride solution, and various microparts such as a screw, a turbine impeller, and a drill are fabricated successfully.