| 摘要 |
PURPOSE:To obtain a photomask blank capable of forming a pattern of desired line width by successively laminating a light shading film and a reflection preventing film made of chromium containing at least chromium fluoride on one of the main surfaces of a light-transmitting substrate. CONSTITUTION:The reflection preventing film 8 contains chromium fluoride, thus permitting the film 8 to be retarded in etching speed of the film pattern 8 and restrained and prevented from excessive progress of etching, the pattern edges to be made almost perpendicular to one of the main surfaces of the transmitting substrate 6, a side etch amount to be made slight, and accordingly, a photomask having a desired line width to be manufactured, the etching speed of the film 8 to be changed by changing the content of chromium fluoride, consequently, the photomask having the desired line width to be fabricated by controlling the etching speed of the film 8 in accordance wit the etching speed of the light shading film 7 under the film 8. |
