Sumco Corporation

Hideki Nishihata

Nobuyuki Morimoto

Akihiko Endo

Satoshi Murakami

Tatsumi Kusaba

Seiichi Nakamura

Riyuusuke Kasamatsu

Yoshiro Aoki

Akira Bando

Kazuo Mera

Etsurou Morita

Nobuo Tsumaki

Tomoji Watanabe

Isoroku Ono

Yoshihisa Nonogaki

Tsuneo Hayashi

Yoichi Kurosawa

Kazunori Tsubuku

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

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

The thickness of a semiconductor wafer layer, extending from a mirror-finished surface thereof to a solid-state image sensing device, is measured. Based on the residual thickness data, plasma etching is performed from the mirror-finished surface until a predetermined thickness is reached by controlling the plasma etching amount. By doing this, it is possible to reduce variation in the thickness of the solid-state image sensing device at low cost without causing an increase in the number of processes.

Method of controlling film thinning of semiconductor wafer for solid-state image sensing device

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

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

In a method for producing a bonded wafer by bonding a wafer for active layer to wafer for support layer and then thinning the wafer for active layer, a terrace grinding for forming a terrace portion is carried out prior to a step of exposing the oxygen ion implanted layer to thereby leave an oxide film on a terrace portion of the wafer for support layer.

Method for producing bonded wafer

A thickness of silicon oxide film of a wafer for active layer is controlled to be thinner than that of buried silicon oxide film. Consequently, uniformity in film thickness of the active layer of a bonded wafer is improved even if a variation in the in-plane thickness of the silicon oxide film is large at a time of ion implantation. Furthermore, since the silicon oxide film is rather thinner and thereby the ion implantation depth is relatively deeper, damages to the active layer and the buried silicon oxide film caused by the ion implantation can be reduced.

Method for manufacturing bonded wafer

Hydrogen gas is ion-implanted into a silicon wafer for active layer via an insulating film, and thus ion-implanted wafer is then bonded with a supporting wafer via an insulating film interposed therebetween. This bonded wafer is heated to 500&#xb0; C., so that a part of the bonded wafer is cleaved and separated, thereby producing an SOI wafer. Subsequently, thus-obtained SOI wafer is subjected to a heat treatment in an argon gas atmosphere. After that, the SOI wafer is subjected to an oxidation process in an oxidizing atmosphere, and thus formed oxide film is removed using an HF solution. Consequently, the surface of the SOI wafer is recrystallized and thus planarized.

Method for producing SOI wafer

In the production process of an SOI substrate using a hydrogen ion implantation method, a process is provided for cleaning the substrate which can prevent formation of voids when bonding substrates and formation of blistering after exfoliation. In the process for cleaning, cleaning of the substrate is performed before performing hydrogen ion implantation. As the cleaning method, one or more of a combination selected from the group consisting of SC-1 cleaning, SC-1 cleaning+SC-2 cleaning, HF/Ocleaning, and HF cleaning+Ocleaning, can be used.

Process for cleaning silicon substrate

Hydrogen gas is ion-implanted into a wafer for active layer via an oxide film. The wafer for active layer is bonded with a supporting wafer using the oxide film as the bonding surface. The bonded wafer is subjected to a heat treatment at the temperature in a range of 400&#xb0; C. to 1000&#xb0; C. As a result of this heat treatment, the bonded wafer is cleaved at the site of ion-implanted layer as the interface thereby producing an SOI wafer. In this heat treatment for cleavage, the temperature difference within the surface of the bonded wafer is controlled to be within 40&#xb0; C. Consequently, the wafer can be cleaved and separated completely across its entire surface at the site of the ion-implanted layer as the interface without leaving any regions uncleaved.

A bonded wafer is produced by implanting ions of a light element into a wafer for active layer to a predetermined depth position to form an ion implanted layer, bonding the wafer for active layer to a wafer for support substrate directly or through an insulating film of not more than 50 nm, exfoliating the wafer for active layer at the ion implanted layer and thinning an active layer exposed through the exfoliation to form the active layer having a predetermined thickness, in which the thickness of the active layer before the thinning is not more than 750 nm and an elongation of slip dislocation in a strength test of the wafer for active layer before the bonding is not more than 100 &#x3bc;m at a predetermined thickness.

Method of producing bonded wafer

This apparatus for manufacturing semiconductor substrates has support disks and holding units holding semiconductor substrates on the support disks. The holding unit has a stopper which is formed of a conductive material and holds the brim of the semiconductor substrate, a stopper holder which supports the stopper at the outer circumferential portion thereof, a retaining member which retains the stopper to the support disk, and a heating unit which heats the stopper.

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Tokyo, Japan

Hideki Nishihata