Patent ID: 11914284
Assignee: AGC INC.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 15:
16. A method of manufacturing a reflective mask blank comprising:
forming a multilayer reflective film on a substrate, the multilayer reflective film reflecting EUV light;
forming a protection film on the multilayer reflective film, the protection film protecting the multilayer reflective film; and
forming a phase shift film on the protection film, the phase shift film shifting a phase of the EUV light on the protection film, wherein
the phase shift film contains at least one first element X1 selected from the first group consisting of ruthenium (Ru), iridium (Ir), platinum (Pt), palladium (Pd), and gold (Au), and at least one second element X2 selected from the second group consisting of oxygen (O), boron (B), carbon (C), and nitrogen (N),
in the phase shift film, a chemical shift of a peak of 3d5/2 or a peak of 4f7/2 of the first element X1 observed by X-ray electron spectroscopy is less than 0.3 eV,
the phase shift film contains a third element X3 whose standard Gibbs energy of formation of at least one of an oxide, boride, carbide, and nitride is less than or equal to −500 kJ/mol, and
in the phase shift film, a chemical shift of a peak of the third element X3 observed by X-ray spectroscopy is greater than or equal to 1.0 eV.