While there have been many attempts at patterning cells onto substrates, a reliable method for trapping cell clusters and forming cell arrays in a predefined geometry remains to be demonstrated. We intend to develop a multielectrode array platform to initially trap cells via dielectrophoresis (DEP) and to later measure their electrical activity. As a first step toward that objective, here we present an interdigitated microfabricated comb structure. We designed an optimal insulation layer via finite element modeling for maximum dielectrophoretic field strength in solution and minimal cell damage. The microfabricated structure was combined with a microfluidic channel to vertically constrain cell position. With the objective of capturing cells onto the substrate, we here show that there is an optimal thickness of dielectric which limits electrolysis in solution and still allows for sufficient dielectrophoretic force on the cells to pull them onto the surface.