An improved and new process of fabricating high dielectric constant MIM capacitors. The light sources andor the member for conducting current to the light sources are at least in part surrounded with the casing part. A first edge guide is provided on the supporting face so as to be slidable in a second direction perpendicular to the first direction. Additionally, the method includes forming troughs in a substrate of the wafer based on the patterning of the photoresist, wherein the ring blocks formation of the troughs underneath the ring.