Patent ID: 8198118

Claim:
A mask forming method comprising: providing a substantially light transparent portion; forming a phase shifting layer over the substantially light transparent portion; forming a substantially light shielding layer disposed over the phase shifting layer; forming at least one barrier layer deposited disposed over the substantially light shielding layer, an uppermost portion of said substantially light shielding layer not comprising anti-reflective properties, each barrier layer of said at least one barrier layer not comprising a Cr-based layer, said at least one barrier layer comprising an uppermost hardmask layer and an underlying anti-reflective layer; forming a resist layer disposed over the at least one barrier layer; patterning the resist layer for producing a circuitry pattern; carrying out an etching process according to the circuitry pattern to expose a portion of the substantially light transparent portion to form a mask; and wherein following the etching process at least a portion of the phase shifting layer, the light shielding layer and the at least one barrier layer having anti-reflective properties remains over portions of the light transparent portion.