Hoya Corporation

Nippon Steel Corporation

Minoru Sugawara

Masato Kobayashi

Kazuhide Yamashiro

Takashi Miyagi

Yasuharu Tanaka

Misao Ogawa

Hiroyuki Nagasawa

Yohichi Yamaguchi

Junki Natori

Yoh-Ichi Yamaguchi

A press forming method includes a first step of pinching one part of a metal sheet by means of a die and a pad, and a second step of moving a punch in a direction in which the punch approaches the die relatively to perform press forming on the metal sheet. The die has a first support surface which has an edge including a curved portion. The pad has a second support surface facing the first support surface of the die. The first support surface includes a first flat portion, and a first deformation portion which protrudes or is recessed with respect to the first flat portion. The second support surface includes a second flat portion which faces the first flat portion, and a second deformation portion which is recessed or protrudes with respect to the second flat portion so as to correspond to the first deformation portion. The first deformation portion is provided on a normal line of the curved portion as viewed from a pressing direction. When a space between the first deformation portion and the second deformation portion is assumed to be a deformation space, in the second step, press forming is performed so that portions of the metal sheet which are on both sides of the deformation space flow into the deformation space, and the metal sheet deforms along the first deformation portion and the second deformation portion in the deformation space.

Press forming method and press apparatus

In a process for the formation of SiC films by a low pressure CVD method using a hot-wall type, a dichlorosilane gas and an acetylene gas are used as a source gas, the flow velocity of the source gases in a reactor is set at not less than 70 cm/second, and the temperature for heating the reactor is set at not more than 1,000.degree. C., whereby SiC films having excellent uniformity in the film thickness and film properties on the surface of one substrate and among different substrates can be produced at a high mass productivity without causing any damage to the reactor from heat during the film formation.

Process for formation of silicon carbide film

In a method of manufacturing an X-ray mask comprising a substrate, an X-ray transmission layer on the substrate, an X-ray absorption layer on the X-ray transmission layer, the X-ray transmission layer is flattened to remove undulation and to make roughness of the X-ray transmission layer smaller than 100 angstroms. The X-ray transmission layer may be formed by silicon carbide or silicon nitride. Alternatively, the X-ray transmission layer may have a multilayer structure of sandwiched structure comprising either a silicon carbide film or a silicon nitride film.

X-ray mask and method of manufacturing an X-ray mask

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Tokyo, Japan

Minoru Sugawara