Process Characterization of Wet Etching for High Aspect Ratio Microneedles Development
Research on microneedles has been increasing rapidly as to overcome the drawbacks of conventional needle which can results in painful during injection, tissue damage and skin infection at the injected site. This paper presents characterization process of wet isotropic etch for solid microneedles array development. This approach utilizes HNA etchant to build the outer shape of solid microneedles. Works has been carried out to investigate the isotropic etching behavior of HNA in different temperature ranging from 20 to 50 degrees, various agitation rate ranging from 0 rpm to 450 rpm and on the various window size ranging from 100 μm to 500 μm. Characterization on those factor, determine the effect of vertical and lateral etch rate variations, surface quality and the geometry obtained. The experimental responses of vertical etch rate, lateral etch rate and high aspect ratio reported. The obtained etching properties will be applied to develop recipes to fabricate outer shape of solid microneedles’ tip.
Selin Teo, A. Q. Liu, H. Li and B. Tarik
N. A. Aziz et al., "Process Characterization of Wet Etching for High Aspect Ratio Microneedles Development", Advanced Materials Research, Vol. 74, pp. 341-344, 2009