Blank for alternating PSM photomask with charge dissipation layer

A phase-shift masking (PSM) photomask comprising:

• a transparent substrate;
• a conductive layer formed on the transparent substrate, the conductive layer being electrically conductive;
• and
• a pattern layer formed on the conductive layer, the pattern layer comprising a first aperture and a second aperture for transmitting radiation in a first phase and a second phase, respectively, the first phase and the second phase being substantially 180 degrees out of phase, wherein the first aperture is formed in at least the pattern layer, and wherein the second aperture is formed in the pattern layer, the conductive layer, and the transparent substrate.

A photomask blank for forming a phase-shift masking (PSM) photomask, the photomask blank comprising:

• a transparent substrate for forming first portions of first apertures;
• a conductive layer for at least forming second portions of the first apertures, the conductive layer being formed on the transparent substrate;
• and
• a pattern layer for at least forming third portions of the first apertures and first portions of second apertures, the pattern layer being formed on the conductive layer,
• wherein a difference in a thickness of the transparent substrate at the first and second apertures provides a phase shift differential for the PSM photomask.

A method for creating a phase-shift masking (PSM) photomask from a blank comprising a transparent substrate, a conductive layer formed on the transparent substrate, a pattern layer formed on the conductive layer, and a first resist layer formed on the conductive layer, the method comprising:

• patterning the first resist layer with a first pattern, the first pattern comprising a first feature and a second feature;
• performing a first etch operation to transfer the first pattern into the pattern layer, the first feature and the second feature controlling the formation of a first aperture and a second aperture, respectively, in the pattern layer;
• stripping the first resist layer;
• applying a second resist layer over the pattern layer;
• exposing a third feature into the second resist layer, the third feature being positioned over the second aperture;
• developing away the third feature in the second resist layer;
• and
• performing a second etch operation through the second aperture, wherein the second etch operation etches through the conductive layer and into the transparent substrate.

An integrated circuit (IC) produced by a process comprising a photolithography operation, the photolithography operation being performed using a phase-shift masking (PSM) photomask, the PSM photomask comprising:

• a transparent substrate;
• a conductive layer formed on the transparent substrate;
• and
• a pattern layer formed on the conductive layer,
• wherein a first aperture extends through the pattern layer and the conductive layer into the transparent substrate, and
• wherein a second aperture extends through at least the pattern layer.