Hitachi, Ltd.

Hiroaki Oizumi

Kozo Mochiji

Takeshi Kimura

Taro Ogawa

Yasunari Soda

Shigeo Moriyama

Takashi Soga

Masaaki Itou

Tsuneo Terasawa

Seiichi Murayama

Shinji Okazaki

Eiji Takeda

Isao Ochiai

Masaaki Ito

Shimpei Iijima

Seiji Yamamoto

An optical element which allows replication of a refined pattern and a projection exposure apparatus employing the optical element are disposed so that side face portions of predetermined patterns which create shadows from oblique incident exposure radiation may be minimized at a predetermined incidence angle of vacuum ultrasonic radiation or X-radiation, or the patterns of the optical element are formed such that the direction in which incident radiation is reflected regularly and the direction of side faces of the patterns may extend in parallel to each other. When the optical element is irradiated to replicate or image the patterns of the optical element, refined patterns can be replicated or imaged.

Optical element and projection exposure apparatus employing the same

In an X-ray exposure method, consideration was made to application of a concept of a phase shift method which is used for a light exposure method, in order to improve the resolution. As a result, phase shift layers made of a material having an appropriate refractivity are provided on side walls of an absorbing pattern of an X-ray mask to improve the resolution by an interference effect. One or more layers made of a material having a refractivity different from that of the absorbing pattern are formed on the side walls of the absorbing pattern of the X-ray mask.

X-ray exposure method with an X-ray mask comprising phase shifter

Reduction projection type X-ray lithography with an exposing beam wavelength of 40-150A, longer than in conventional 1:1 proximity exposure, has a high-vacuum space. This would reduce wafer replacement work efficiency and contaminate optical mirrors with substances released by a resist decomposed during exposure except for separating an optical system chamber and a wafer exposing chamber by a differential pumping section and a thin-film window. Wafer exposure is under atmospheric pressure, improving productivity, accuracy of exposure and longevity of the optical devices.

Projection type X-ray lithography apparatus

In a reflection mask, there is formed at least one laminate structure comprising a high reflectivity portion, a middle portion and a high reflectivity portion. When there is a defect in the high reflectivity portion as the top layer, this high reflectivity portion and the underlying middle portion are removed in that defective position, thereby allowing the high reflectivity portion as the bottom layer to be exposed to repair the defect.

Reflection mask

An X-ray mask comprises an absorber pattern composed of a material capable of absorbing X-ray, a mask substrate for supporting the absorber pattern, composed of a material capable of transmitting X-ray, and a support frame for supporting the mask substrate, wherein the mask substrate is composed of a mask substrate material whose impurity content is suppressed to reduce positional distortions generated by X-ray radiation. Generation of positional distortions by X-ray exposure is inhibited and an arrangement of mask pattern can be ensured with a high precision.

X-ray mask and method for producing same

The method for production of a graft copolymer according to the present invention includes the step of adding to a base polymer capable of forming first radicals when irradiated with radiation an additive capable of combining with said first radicals to form second radicals stable against oxygen, the step of irradiating said base polymer containing the additive with radiation, and the step of introducing a monomer under an atmosphere free from oxygen, thereby to graft copolymerize said irradiated base polymer and said monomer.

Method for production of graft copolymer, pattern replication method,

The method for forming a pattern according to the present invention comprises a step of irradiating a resist layer applied on a substrate to be worked with X-ray radiation through a mask in an oxygen-containing atomsphere to expose said resist layer, a step of decomposing a peroxide produced within said exposed resist layer in an atmosphere free from oxygen, a step of introducing a monomer into said atmosphere free from oxygen to conduct graft copolymerization of said resist layer at the exposed portion with said monomer, and a step of developing said resist layer to remove said resist layer at the portion remaining ungrafted.

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Kokubunji, Japan

Hiroaki Oizumi