Patent ID: 8877605

Claim:
A method of etching a silicon substrate comprising: providing a silicon substrate including a first surface and a second surface; etching a plurality of grooves spaced apart from each other from the first surface of the silicon substrate, adjacent grooves of the plurality of grooves having a spacing when viewed from a direction perpendicular to the first surface of the silicon substrate; depositing a dielectric material on the first surface of the silicon substrate and into the plurality of grooves; providing a mask on the second surface of the silicon substrate that defines a dimension of interest that is smaller than the spacing between the adjacent grooves when viewed from the direction perpendicular to the first surface of the silicon substrate, and aligning the mask relative to the plurality of grooves so that the dimension of interest is between adjacent grooves; and etching a hole defined by the dimension of interest through the silicon substrate from the second surface of the substrate to the dielectric material, the hole being contained within the confines of the adjacent grooves.