Dual-wavelength exposure for reduction of implant shadowing

摘要

A method for generating a photoresist structure is disclosed in which a layer of photoresist is deposited over a semiconductor substrate. In a first exposure, the layer of photoresist is exposed to deep ultraviolet light. A second exposure is then performed using a different wavelength of light to pattern the layer of photoresist. The photoresist is then developed so as to form a photoresist structure having reduced thickness and rounded corners. This gives a photoresist structure having a reduced shadow area. An angled ion implant can then be performed using the photoresist structure as a mask.