Sumco Corporation

Tatsumi Kusaba

Akihiko Endo

Hidehiko Okuda

Nobuyuki Morimoto

Hideki Nishihata

Etsurou Morita

Yoshihisa Nonogaki

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

This p-type silicon wafer was subjected to heat treatment to have a resistivity of 10 &#x3a9;&#xb7;cm or more, a BMD density of 5&#xd7;10defects/cmor more, and an n-type impurity concentration of 1&#xd7;10atoms/cmor less at a depth of within 5 &#x3bc;m from a surface of the wafer. This method for heat-treating p-type silicon wafers, the method includes the steps of: loading p-type silicon wafers onto a wafer boat, inserting into a vertical furnace, and holding in an argon gas ambient atmosphere at a temperature of 1100 to 1300&#xb0; C. for one hour; moving the wafer boat to a transfer chamber and discharging the silicon wafers; and transferring to the wafer boat silicon wafers to be heat treated next, wherein after the discharge of the heat-treated silicon wafers, the silicon wafers to be heat-treated next are transferred to the wafer boat within a waiting time of less than two hours.

P-type silicon wafer and method for heat-treating the same

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

Even if an oxygen ion implanted layer in a wafer for active layer is not a completely continuous SiOlayer but a layer mixed partially with Si or SiO, it is removed by here is provided a method for producing a bonded wafer in which it is possible to remove an oxygen ion implanted layer effectively as it is by repetitive treatment with an oxidizing solution and HF solution at a step of removing the oxygen ion implanted layer in a bonded wafer.

Method for producing bonded wafer

The present invention provides a method of manufacturing a bonded wafer. The method comprises an oxidation step in which an oxide film is formed on at least one surface of a base wafer, a bonding step in which the base wafer on which the oxide film has been formed is bonded to a top wafer to form a bonded wafer, and a thinning step in which the top wafer included in the bonded wafer is thinned. The oxidation step comprises heating the base wafer to a heating temperature ranging from 800 to 1300&#xb0; C. at a rate of temperature increase ranging from 1 to 300&#xb0; C./second in an oxidizing atmosphere, and the bonding step is carried out so as to position the oxide film formed in the oxidation step at an interface of the top wafer and the base wafer.

Method of manufacturing bonded wafer

There is provided a layer transferred wafer subjected to a process for regenerating to be reused many times for an SOI layer wafer which is used to manufacture an SOI wafer with an excellent process yield in which oxygen precipitate nuclei or oxygen precipitates are eliminated and generation of HF defects are inhibited by performing the process for regenerating the layer transferred wafer generated as a by-product by an ion implantation separation method. The process for regenerating a layer transferred wafer in which the layer transferred waferobtained as a by-product in manufacturing a bonded SOI waferby an ion implantation separation method so as to be reused for an SOI layer waferof the bonded SOI wafercomprises: rapidly heating the layer transferred waferin an oxidizing atmosphere, then holding it for a fixed time and subsequently rapidly cooling it; and mirror-polishing a surface of the layer transferred wafer

Process for regenerating layer transferred wafer

A bonded wafer is produced by a method comprising a step of implanting ions of a light element such as hydrogen, helium or the like into a wafer for active layer at a predetermined depth position to form an ion implanted layer, a step of bonding the wafer for active layer to a wafer for support substrate through an insulating film, a step of exfoliating the wafer at the ion implanted layer, a first heat treatment step of conducting a sacrificial oxidation for reducing damage on a surface of an active layer exposed through the exfoliation and a second heat treatment step of raising a bonding strength, in which the second heat treatment step is continuously conducted after the first heat treatment step without removing an oxide film formed on the surface of the active layer.

A bonded wafer is produced by comprising a step of implanting oxygen ions from a surface of a wafer for active layer to form an oxygen ion implanted layer at a given position inside the wafer for active layer; a step of bonding the wafer of active layer to a wafer for support substrate directly or through an insulating film; a step of subjecting the resulting bonded wafer to a heat treatment for increasing a bonding strength; a step of removing a portion of the wafer for active layer in the bonded wafer to a given position not exposing the oxygen ion implanted layer by a given method; a step of exposing the entire surface of the oxygen ion implanted layer; and a step of removing the exposed oxygen ion implanted layer to obtain an active layer of a given thickness, wherein the step of exposing the entire surface of the oxygen ion implanted layer is carried out by a dry etching under given conditions.

A method for achieving high purity in a jig for semiconductor heat treatment includes subjecting a semiconductor heat treatment jig made of a substrate having a surface covered with a silicon carbide film grown by chemical vapor deposition or a semiconductor heat treatment jig made of a silicon carbide film grown by chemical vapor deposition to high-temperature oxidation heat treatment so as to form an oxide film on a surface of the silicon carbide film, and removing the oxide film.

High purification method of jig for semiconductor heat treatment

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

A high quality bonded substrate is obtained in which generation of microprotrusions and cracked particles are restricted on a surface of an active layer of the bonded substrate and the surface of the active layer is flattened. A laminated body is formed by overlapping a first semiconductor substrate serving as an active layer onto a second semiconductor substrate serving as a support substrate via an oxide film or without an oxide film; the active layer is formed by forming a thin film from the first semiconductor substrate; and the surface of the active layer is flattened by vapor-phase etching. After forming a thin film from the first semiconductor substrate and before flattening the surface of the active layer by the vapor-phase etching, an organic substance adhering to the surface of the active layer is removed and a native oxide film generated on the surface of the active layer is removed after removing the organic substance.

Method for manufacturing bonded substrate and bonded substrate manufactured by the method

The object of the invention is to provide a method for manufacturing an SOI layer which is devoid of damages, has a reduced variation in thickness, and is uniform in thickness. The object is met by providing a method for manufacturing an SOI substrate comprising the steps of forming an oxide film at least on one surface of a first silicon substrate, implanting hydrogen ions from the surface of the first silicon substrate thereby forming an ion-implantation zone in the interior of the first silicon substrate, bonding the first silicon substrate over a second silicon substrate with the oxide film interposed thereby forming a laminated assembly, subjecting the laminated assembly to a first heating treatment consisting of heating at a specified temperature, so that the first silicon substrate is split at the ion-implantation zone thereby manufacturing a bonded substrate, flattening the exposed surface of the SOI layer by subjecting the bonded substrate to wet etching, subjecting the bonded substrate to a second heating treatment consisting of heating at 750 to 900&#xb0; C. in an oxidative atmosphere thereby reducing damages inflicted to the SOI layer, and subjecting the resulting bonded substrate to a third heating treatment consisting of heating at 900 to 1200&#xb0; C. thereby enhancing the bonding strength of the bonded substrate.

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Tokyo, Japan

Tatsumi Kusaba