Nikon Corporation

Other

Sumito Shimizu

Hajime Yamamoto

Kazuaki Suzuki

Toru Nakamura

Atsushi Yamada

Hiroaki Okagawa

Shohei Suzuki

Kazuyuki Tadatomo

Yoshijiro Ushio

Kazumasa Hiramatsu

Tetsuya Oshino

Masahiro Koto

Yutaka Hamamura

Youichiro Ohuchi

Wakako Suganuma

Apparatus and methods are disclosed for inscribing a pattern on a reticle blank to produce a lithography reticle. As a reticle blank is inscribed using a charged particle beam (e.g., electron beam), some of the incident charged particles pass through the reticle blank and are backscattered from underlying structure (e.g., from a stage used to hold the reticle blank during inscription). These backscattered particles reduce the pattern resolution on the reticle. The present apparatus and methods reduce the number of backscattered particles re-entering the reticle blank, thereby improving pattern resolution.

Apparatus and methods for patterning a reticle blank by electron-beam inscription with reduced exposure of the reticle blank by backscattered electrons

Methods are disclosed for performing charged-particle-beam (CPB, e.g., electron-beam) microlithography with reduced Coulomb effects being manifest in pattern images as formed on the surface of a sensitive substrate. The pattern is defined on a segmented reticle, which can be a scattering-stencil reticle or scattering-membrane reticle. In an embodiment, the beam current actually reaching the substrate, as a proportion of beam current actually passing through the reticle, is reduced to 50% or less during exposure of the pattern. To achieve this reduction, the pattern as defined on the reticle can be normal or inverted in tone as required, and the resist on the substrate can be positive or negative in tone as required. In an example embodiment, the beam current reaching the substrate is reduced by establishing an opening ratio of 50% or less for the pattern as a whole as defined on the reticle. The opening ratio is expressed as 100&lsqb;A /(A &plus;A )&rsqb;, wherein A is a total area of the reticle occupied by both the weakly scattering reticle membrane and the highly scattering layer, and A is a total area of the reticle occupied by only the weakly scattering reticle membrane.

Charged-particle-beam microlithography methods exhibiting reduced coulomb effects

A semiconductor light receiving element having a light receiving layer ( ) formed from a GaN group semiconductor, and an electrode ( ) formed on one surface of the light receiving layer as a light receiving surface ( ) in such a way that the light (L) can enter the light receiving layer is provided. When the light receiving element is of a Schottky barrier type, the aforementioned electrode ( ) contains at least a Schottky electrode, which is formed in such a way that, on the light receiving surface ( ), the total length of the boundary lines between areas covered with the Schottky electrode and exposed areas is longer than the length of the outer periphery of the light receiving surface ( ). In addition, when the light receiving element is of a photoconductive type, the aforementioned light receiving layer ( ) is a first conductivity type i layer, and the aforementioned electrode ( ) is an ohmic electrode of one polarity, and an ohmic electrode of the other polarity is formed directly or via a first conductivity type and low resistance GaN group semiconductor layer on the other surface of the light receiving layer ( ).

Semiconductor light receiving element

A method to repair a scattering stencil type mask having a high electron beam scattering property and low electron absorption. In order to correct a defect caused at the time of manufacturing of the mask, which is being used when a reduction projection image is transferred onto a substrate and has a pattern projection portion comprising an electron beam scattering material, a repair membrane is formed in the defective portion of the mask by irradiating a charged particle beam to said defect while a gas including substances having high scattering properties are supplied to the close vicinity of the defective portion.

Method of repairing a mask with high electron scattering and low electron absorption properties

Apparatus and methods are disclosed for measuring changes in light absorption of a sample optical component. The sample is held in a sample holder in a sample chamber during irradiation by an intense light, usually pulsatile light. Molecules of a gas are introduced into the sample chamber as the sample is irradiated. The molecules can be of a material suspected to become adhered to or absorbed by the sample in a way that causes an undesired change in light absorption by the sample. Changes in light absorption by the sample are preferably measured photoacoustically. The molecules of the gas can be generated by controlled irradiation of a 'source material' with a light (which can be the same as used to irradiate the sample) sufficient to generate such molecules of gas from the source material, and routing the gaseous molecules to the sample as the sample is irradiated.

Light absorption measurement apparatus and methods

An etching apparatus comprises a first tank for containing an etchant, a second tank for containing a non-etchant, a partition positioned between the first tank and the second tank and consisting of a plurality of partition planes, and holders for holding a plurality of substrates against the partition. One or more openings are formed in each partition plane of the partition, and the substrates are held against the partition so that the openings formed in the partition planes are closed by the substrates. Each substrate is larger than the associated opening in size and has a top surface and an etching surface on the bottom. Each of the holders holds one of the substrates so that the etching surface of the substrate is exposed to the etchant contained in the first tank through the opening without touching the non-etchant and that the top surface of the substrate is exposed to the non-etchant contained in the second tank without touching the etchant. The size and/or the shape of the opening can be adjusted according to the size and/or the shape of the substrate.

Growing community of inventors

Yokohama, Japan

Sumito Shimizu