JPS6352374B

PURPOSE:To enable to form a fine pattern by forming a primer coating layer composed of an alumino.silicate glass or an alumino.bronsilicate glass on a quartz glass substrate, and by providing a light-shield layer on said primer coating layer. CONSTITUTION:The primer coating layer 4 is formed between the quartz glass substrate 1 and the shield layer 2 to increase an adhesive force of the shield layer 2 against the quartz glass substrate 1. The thin film of the alumino.silicate glass or the alumino.boronsilicate glass is selected as the primer coating layer with regard to the shield layer 2 of the chrom contg. film and the quartz glass substrate 1. The thickness of the primer coating layer 4 is preferably 5-5,000nm ranges. The adhesive force of the shield layer 2 composed of the chrom contg. film formed on the quartz glass substrate is substantially increased by interposing the primer coating layer composed of the alumino.silicate glass or the alumino.boronsilicate glass between said substrate 1 and said shield layer 2, thereby obtaining the photomask blank and the photomask having a high durability.