MASK BLANK, PHASE-SHIFT MASK, AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

WIPO Patent Application WO/2019/230313

A1

Provided is a mask blank equipped with a phase-shift film which has reduced rear-side reflectance and which has both a function of allowing exposure light from an ArF excimer laser to transmit therethrough with a predetermined transmittance, and a function of generating a predetermined phase difference with respect to the transmitting exposure light from the ArF excimer laser. A phase-shift film (2) includes a structure in which a first layer (21) and a second layer (22) are layered in this order from a light-transmissive substrate side. The first layer (21) is provided so as to be in contact with a surface of the light-transmissive substrate (1). When the refractive indexes of the first layer (21) and the second layer (22) at the wavelength of the exposure light from the ArF excimer laser are defined as n1 and n2, respectively, n1