The development of retinal prostheses requires a method for interconnecting an imaging system to the retina. Such a system must be able to individually address and stimulate retinal neurons, a significant advance from current technology. As a step toward this goal, we present a novel electronic-to-biologic interface using microfabricated apertures in a silicon substrate. Apertures are created in a thin silicon nitride membrane, after which the surface is appropriately modified to support cell growth. Excitable cells are seeded on the device and imaged using Ca2+-sensitive fluorescent dyes in either an inverted or confocal microscope. Using rat pheochromocytoma (PC12) cells, we show the ability to stimulate locally through the apertures. The device allows for the stimulation of cells at precise locations, a necessary requirement for future high-resolution retinal prostheses.