Fabrication of pen-shaped microneedle structure by using non-photolithographic pattern transfer

We developed a new fabrication process for pen-shaped microneedle structures by using a non-photolithographic pattern transfer. The process is a combination of anisotropic wet etching and a dicing technology that uses a saw. The process has an advantage, in which altering the groove profile formed in the dicing-saw process easily changes the needle diameter. We fabricated pen-shaped needle structures in a dense array for medical and biological applications. The needle height was larger than 200 /spl mu/m, and the pitch distance was about 200 /spl mu/m in the experiments. The width of the needle ranged from 10 to 30 /spl mu/m. The radius at the needle tip was less than 100 nm.