US Patent 7549224 Methods of making slotted substrates

The described embodiments relate to slotted substrates and methods of making the slotted substrates. One exemplary method patterns a first set of dummy features in a first layer positioned over a first surface of a substrate and patterns a second set of dummy features in a second layer positioned over the first layer. After the method patterns the first set of dummy features and the second set of dummy features, the method further forms a slot in the substrate, at least in part, by allowing an etchant to pass through the first and second sets of dummy features to the first surface.