Systems and Methods for a Narrow Band High Transmittance Interference Filter

A lithography system comprising:

• a light source having a plurality of spectrum peaks;
• a plurality of lenses;
• at least one minor;
• and
• a plurality of filters including an interference filter, the interference filter having a plurality of material layers alternating between high and low refractive indices, deposited on a substrate, a thickness of each of the alternating layers being such that the interference filter allowing one of the plurality of spectrum peaks to pass and blocking the rest of the plurality of spectrum peaks.

A method for fabricating a semiconductor device, the method comprising:

• providing wafer that is to undergo one or more processing steps;
• coating a photoresist layer on the wafer;
• delivering the wafer into a lithography system and performing a patterning process on the wafer, the lithography system having an interference filter that includes:
• a transparent substrate having a front surface and a back surface;
• a plurality of alternating material layers formed over the front surface of the transparent substrate, wherein a sequence of the material layers alternates between relatively high and relatively low refractive indices;
• and
• an anti-reflective structure formed over the back surface of the transparent substrate.