Sumco Corporation

Chugai Seiyaku Kabushiki Kaisha

Tokyo Medical and Dental University

Nobuyuki Morimoto

Akihiko Endo

Hideki Nishihata

Satoshi Murakami

Tatsumi Kusaba

Tsuyoshi Shimoboji

Etsurou Morita

Kazunari Akiyoshi

Tai Hirakura

Tamio Motoyama

The present invention provides a composition comprising a hyaluronic acid derivative having a crosslinking group(s) and a hydrophilic polysaccharide derivative having a hydrophobic group(s), wherein the hyaluronic acid derivative having a crosslinking group(s) is prepared by crosslinkage formation reaction in hyaluronic acid or a derivative thereof having a crosslinkable group(s) in the presence of the hydrophilic polysaccharide derivative wherein the hydrophilic polysaccharide derivative may have a crosslinkable group(s).

Hybrid gel comprising chemically crosslinked hyaluronic acid derivative and  pharmaceutical composition comprising the same

The present invention provides a method of manufacturing a bonded wafer. The method includes ozone washing two silicon wafers to form an oxide film equal to or less than 2.2 nm in thickness on each surface of the two silicon wafers, and bonding the two silicon wafers through the oxide films formed to obtain a bonded wafer.

Method of manufacturing bonded wafer

There is provided a method for suppressing the occurrence of defects such as voids or blisters even in the laminated wafer having no oxide film wherein hydrogen ions are implanted into a wafer for active layer having no oxide film on its surface to form a hydrogen ion implanted layer, and ions other than hydrogen are implanted up to a position that a depth from the surface side the hydrogen ion implantation is shallower than the hydrogen ion implanted layer, and the wafer for active layer is laminated onto a wafer for support substrate, and then the wafer for active layer is exfoliated at the hydrogen ion implanted layer.

Method for producing semiconductor substrate

A bonded wafer is produced by directly bonding a silicon wafer for active layer and a silicon wafer for support substrate without an insulating film and thinning the silicon wafer for active layer to a given thickness, in which a silicon wafer cut out from an ingot at a cutting angle of 0-0.1&#xb0; (compound angle) with respect to a predetermined crystal face is used in each of the silicon wafer for active layer and silicon wafer for support substrate.

Bonded wafer and method for producing bonded wafer

There is provided a bonded wafer having excellent thickness uniformity after thinning but also good surface roughness and being less in defects. In the production method of a bonded wafer by bonding a wafer for active layer to a wafer for support substrate and thinning the wafer for active layer,

Method for producing bonded wafer

In a method for producing a bonded wafer by bonding a wafer for active layer and a wafer for support layer and thinning the wafer for active layer according to the invention, oxygen ions are implanted into the wafer for active layer at a state of holding a temperature of the wafer for active layer below 200&#xb0; C. under a dose of 5&#xd7;10to 5&#xd7;10atoms/cm, whereby there can be obtained a bonded wafer being excellent in the thickness uniformity after thinning and having a dramatically improved surface roughness.

Method for producing a bonded wafer

There is provided a method for suppressing the occurrence of defects such as voids or blisters even in the laminated wafer having an oxide film of a thickness thinner than the conventional one, wherein hydrogen ions are implanted into a wafer for active layer having an oxide film of not more than 50 nm in thickness to form a hydrogen ion implanted layer, and ions other than hydrogen are implanted up to a position that a depth from the surface side the hydrogen ion implantation is shallower than the hydrogen ion implanted layer, and the wafer for active layer is laminated onto a wafer for support substrate through the oxide film, and then the wafer for active layer is exfoliated at the hydrogen ion implanted layer.

Method of producing semiconductor substrate having an SOI structure

A bonded silicon wafer is produced by a method including an oxygen ion implantation step on a silicon wafer for active layer having the specified wafer face; a step of bonding the silicon wafer for active layer to a silicon wafer for support; a first heat treatment step; an inner SiOlayer exposing step; a step of removing the inner SiOlayer; and a planarizing step of polishing a silicon wafer composite or subjecting the silicon wafer composite to a heat treatment in a reducing atmosphere (a second heat treatment step).

Method for producing bonded silicon wafer

A method of producing a bonded wafer, comprising: performing bonding of a first semiconductor wafer and a second semiconductor wafer without interposing an insulation film in between; and performing thinning of the second semiconductor wafer, wherein surface portions at least including bonded surfaces of the first semiconductor wafer and the second semiconductor wafer have an oxygen concentration of 1.0&#xd7;10atoms/cm(Old ASTM) or less.

Method of producing bonded wafer

Adhesion of particles due to static buildup during a laminated substrate manufacturing process is constrained, so as to reduce generation of a void or a blister in a lamination step and improve yield. A laminateis formed by superimposing a first semiconductor substrate, which is to be an active layer, on a second semiconductor substrate, which is to be a supporting substrate, via an oxide film. Electric resistance of either or both of the first and second semiconductor substratesandbefore superimposition is 0.005-0.2 &#x3a9;cm.

Laminated substrate manufacturing method and laminated substrate manufactured by the method

The present invention provides a method of manufacturing a bonded wafer. The method includes forming an oxygen ion implantation layer in an active layer wafer having a substrate resistivity of 1 to 100 m&#x3a9;cm by implanting oxygen ions in the active layer wafer, bonding a base wafer and the active layer wafer directly or through an insulating layer to form a bonded wafer, heat treating the bonded wafer to strengthen the bond and convert the oxygen ion implantation layer into a stop layer, grinding, polishing, and/or etching, from the active layer wafer surface side, the bonded wafer in which the bond has been strengthened to expose the stop layer on a surface of the bonded wafer, removing the stop layer, and subjecting the bonded wafer from which the stop layer has been removed to a heat treatment under a reducing atmosphere to diffuse an electrically conductive component comprised in the active layer wafer.

A bonded wafer formed by directly bonding a wafer for active layer and a wafer for support substrate without an insulating film and thinning the wafer for active layer is evaluated by a method comprising steps of removing native oxide from a surface of an active layer in the bonded wafer, subjecting the bonded wafer to an etching with an etching liquid having an etching rate to a material constituting the wafer faster than that to an oxide of the material to remove at least a whole of the active layer, and detecting island-shaped oxides exposed by the etching, in which the etching is carried out so as to satisfy a relation of T&#x2266;X&#x2266;T+500 nm wherein T is a thickness of the active layer (nm) and X is an etching depth (nm) to detect the number and size of the island-shaped oxides.

Method for evaluation of bonded wafer

Since a supporting wafer contains boron of 9&#xd7;10atoms/cmor more, therefore a part of the metal impurities in an active layer wafer and the metal impurities in the wafer can be captured by the boron during the heat treatment for bonding. As a result, metal contamination in the active layer can be reduced. Moreover, the wafer strength is enhanced, thus preventing the wafer slipping. Since the wafer has no COP, micro voids are not detected in the LPD evaluation of the active layer, thereby improving the reliability of the evaluation. Such a bonded wafer can be manufactured at a low cast.

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Tokyo, Japan

Nobuyuki Morimoto