Fabrication of Tungsten Micro Needle Arrays Using Laser Beam Machining

Micro needle arrays have been widely used within medical contexts, such as for drug delivery and nervous electrodes, and its fabrication methods have attracted attention recently. This paper describes a novel fabrication method for micro needle arrays on a tungsten metal plate using only laser beam machining. Tungsten material was ablated as combining laser beam scanning path to control needle structure. Overlapping laser beams from the combined scanning path causes thermal accumulation phenomena which removes the material. In this paper, controlling laser scanning path (Line Interval, Line Space, Number of Lines) and machining conditions (Power, Number of Scan), and the changing length and pitch of the micro needles were measured through SEM. Moreover, the piercing force for application in drug delivery and nervous electrodes was measured with a load cell system.