To provide a phase shift photomask blank having excellent chemical resistance and optical properties, a phase shift photomask fabricated by using the photomask blank, fabrication processes of the photomask blank and photomask and equipment for fabrication of the photomask blank.
The fabrication process of this phase shift photomask blank is for forming thin films on a substrate by a reactive sputtering method, wherein the substrate is passed on a sputtering target at least four times to form homogeneous thin films 81, 82, 83 and 84, gaseous NO is used as a reactive gas, a mixed target consisting of molybdenum and silicon is used as a sputtering target, also a transparent substrate is used as a substrate on which the thin films 81, 82, 83 and 84 should be formed and as a result, an optical-transmissive film capable of transmitting intense light is formed on the transparent substrate. Further, in the fabrication, each of the thin films 81, 82, 83 and 84 is formed through an aperture having sufficiently greater length along the transfer direction of the substrate while allowing even regions where the maximum value of the deposition rate of a target component is ≤90% to contribute to the film formation. The phase shift photomask blank thus fabricated is performed to pattern forming treatment.
KAWADA SUSUMU
YAMAMOTO TSUNEO
AMANO JUN
KOBAYASHI RYOICHI
YOSHIOKA NOBUYUKI
MITSUBISHI ELECTRIC CORP