Creation of the high functional painless micro needle using the sputtering method

We have established sputtering method to produce a painless micro needle which is one of the vacuum deposition methods. The needle is created on a wire substrate fixed to a jig rotating under a constant velocity. However, at present, micro painless needle having a pentagon cross sectional shape in consideration of high rigidity and biological contact area, has not been made. In order to create an equilateral pentagon cross section, rotation of the jig was controlled to use the simulation. However, there was little difference in cross-section, showing a small difference in thickness. It is necessary to search experimental conditions which can make a larger difference to film thickness. Therefore, experiments for making a pentagon cross section were performed using the light reflector. A corner was made by controlling the speed of rotation and setting the reflector in 85 degrees. To obtain a film thickness difference of 9.07 [μm] by rotating the jig in 0.0139 [μm] per unit turn would be 653 times. Thus, it is considered that the pentagon cross section needle with the optimal shape could be made by setting the reflector between the angle from 0 degree to 36 degree.