Application of Laser Scan Lithography to Fabrication of Microcylindrical Parts

Abstract

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 mm 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 mm 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.

Lithography onto Surfaces of Fine-Diameter Pipes Using Rotary Scan-Projection Exposure

“…Each resist was coated using the dip method [8]. Resist thicknesses were controlled by changing the relative draw-up speed, as shown in Fig.…”

“…To answer the requirement, various researches on developing lithography systems for replicating or delineating patterns on cylindrical materials were carried out [1][2][3][4][5][6][7]. The authors also developed laser-scan exposure systems onto fine wires and pipes with diameters of 40-500 µm [8][9][10][11][12][13]. It was demonstrated that very precise patterns were arbitrarily delineated on surfaces of such very fine cylindrical materials.…”

“…It was demonstrated that very precise patterns were arbitrarily delineated on surfaces of such very fine cylindrical materials. In addition, fabrication processes of fine cylindrical micro-components such as coil springs and pipes with multi-holes were also developed [8][9][10][11] [13].…”

Development of minimally invasive medical tools using laser processing on cylindrical substrates

“…In addition, pattern formation has been performed by photolithography on a cylindrical surface, by exposing a resist to laser [11] or electron beam [12] radiation, producing the pattern without employing a mask. However, a single layer is obtained in all cases.…”

Fabrication of micro-coils using laser scan lithography on copper pipes

“…Here, a new resist coating mechanism and a new exposure system are developed [1,2], and etching conditions are investigated. As a result, micro-parts finer than those fabricated by the other method [3,4] are obtained.…”