▎ 摘　　要

NOVELTY - A catalyst comprises (i) 1st layer (17) comprising a transition metal; (ii) base layer (15); and (iii) an interlayer (16) which is disposed between base layer and 1st layer. USE - A catalyst for synthesizing graphene used for multi-layered pellicle stack, pellicle and lithography apparatus (all claimed). ADVANTAGE - The interlayer is disposed between the base layer and 1st layer, which affords a smoother surface of the catalytic 2nd layer, and higher quality graphene. Catalyst comprising an interlayer of metal oxide or silicide offers improved performance. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparing a catalyst which involves (i) providing an interlayer (16) comprising a metal oxide, metal silicide, and/or carbon on base layer (15); and (ii) providing a 1st layer (17) comprising a transition metal; (2) synthesizing graphene which involves (i) depositing carbon onto a surface of catalyst; and (ii) forming a graphene layer on the catalyst; (3) multi-layered pellicle stack comprising layers of amorphous carbon, graphene, carbide of transition metal, silicon oxide (SiO2) and carbon silicide (C-Si); (4) pellicle comprising graphene; and (5) lithography apparatus comprising a pellicle. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic cross sectional view of the interlayer through a catalyst. Base layer (15) Interlayer (16) 1st layer (17)