Fabrication of Ti Retinal Microtacks Using Ultra-High-Precision Micromilling

To adhere an artificial retinal implant onto the epiretinal surface of the eye, our group has designed retinal microtacks. The microtacks were fabricated by first bonding titanium foil to a silicon wafer; the tacks were then machined using an ultra-high precision micromilling technique with a 150-μm end-mill. The versatility of the micromilling technique allowed a partially conical, tapered tip to be added to the Ti tack, which created a sharp point. The Ti tacks average overall length and width were measured to be within 1% and 6%, respectively, of the design. Additionally, the grip width, stop thickness, and the tip taper angle of the Ti tacks were within 3%, 9%, and 4%, respectively, of the design.