Method of fabricating devices using an attenuated phase-shifting mask and an attenuated phase-shifting mask

Abstract

An improved attenuated phase-shifting mask (APSM) for use with an imaging tool for forming a patterned feature on a photoresist layer of a semiconductor wafer. The APSM has a transmissive region for substantially transmitting light therethrough to form a projected image substantially shaped as the patterned feature on the photoresist layer. The APSM also has an attenuating and phase-shifting region, contiguous with the transmissive region, for absorbing a portion of the light incident thereon and for shifting the phase of the incident light by a predetermined number of degrees relative to that of the light transmitted through the transmissive region so as to destructively interfere with the light transmitted through the transmissive region and to project a background image. The transmissive region has a dimension d dimensioned such that the intensity of the image projected by the transmissive region is darker than the intensity of the background image projected by the attenuating and phase-shifting region of the mask and that the intensity of the background image is substantially uniform.