Shin-etsu Handotai Co., Ltd.

Shin-etsu Handotai, Ltd.

Norihiro Kobayashi

Hiroji Aga

Masaro Tamatsuka

Shoji Akiyama

Nobuhiko Noto

Tohru Ishizuka

Takao Abe

Toru Ishizuka

Satoshi Oka

Takatoshi Nagoya

Wei Feig Qu

Kiyoshi Mitani

Hiroshi Takeno

Masahiro Kato

Shoichi Takamizawa

Yuuichi Matsumoto

Makoto Iida

Isao Yokokawa

Masaru Shinomiya

Masatake Nakano

Taishi Wakabayashi

Kenji Meguro

Yuichi Matsumoto

Toshihiko Miyano

Yasuo Nagaoka

Tomohiko Ohta

Masatake Katayama

Ken Aihara

Yoshinori Hayamizu

Tatsuo Enomoto

Masayuki Imai

Satoshi Tobe

Osamu Ishikawa

Yukio Inazuki

Jun-ichiro Furihata

Kazuo Mamada

Katsunori Koarai

Hiroyuki Oonishi

A method for manufacturing a bonded SOI wafer, including depositing a polycrystalline silicon layer on a base wafer, forming an insulator film on a bond wafer, bonding the bond wafer and a polished surface of the silicon layer with the insulator film interposed, and thinning the bond wafer, wherein a silicon single crystal wafer having a resistivity of 100 &#x3a9;&#xb7;cm or more is the base wafer, the step of depositing the silicon layer includes a stage of forming an oxide film on the surface of the base wafer, and the silicon layer is deposited between 1050&#xb0; C. and 1200&#xb0; C. Accordingly, the method enables a polycrystalline silicon layer to be deposited while preventing the progress of single crystallization even through a heat treatment step in the SOI wafer manufacturing process or a heat treatment step in the device manufacturing process and can improve throughput in the polycrystalline silicon layer depositing step.

Method for manufacturing bonded SOI wafer

A bonded SOI wafer is manufactured by bonding a bond and a base wafer, each composed of a silicon single crystal, via an insulator film, depositing a polycrystalline silicon layer on the bonding surface side of the base wafer, polishing a surface of the polycrystalline silicon layer, forming the insulator film on the bonding surface of the bond wafer, bonding the polished surface of the polycrystalline silicon layer and the bond wafer via the insulator film, and thinning the bonded bond wafer to form an SOI layer; wherein, the base wafer is a silicon single crystal wafer having a resistivity of 100 &#x3a9;&#xb7;cm or more, depositing the polycrystalline silicon layer further includes a stage for previously forming an oxide film on the surface of the base wafer on which the polycrystalline silicon layer is deposited, and the polycrystalline silicon layer is deposited at a temperature of 900&#xb0; C. or more.

Method for manufacturing a bonded SOI wafer and bonded SOI wafer

Method for manufacturing bonded SOI wafer by bonding bond wafer and base wafer each composed of silicon single crystal with insulator film being interposed therebetween, including steps of: depositing polycrystalline silicon layer on bonding surface side of base wafer; polishing surface of polycrystalline silicon layer to obtain polished surface; forming thermal oxide film on polished surface; forming insulator film on bonding surface of bond wafer; bonding step of bonding bond and base wafers by bringing insulator and oxide films into close contact with each other; and thinning bonded bond wafer to form SOI layer, wherein silicon single crystal wafer having resistivity of 100 &#x3a9;&#xb7;cm or more is used as base wafer, thermal oxide film formed on polished surface has thickness of 15 nm or more with RMS of 0.6 nm or less, and any heat treatment after bonding step is performed with maximum treatment temperature of 1150&#xb0; C. or less.

Method for manufacturing a bonded SOI wafer by bonding a bond wafer and base wafer, each composed of a silicon single crystal, via an insulator film, including the steps: depositing a polycrystalline silicon layer on the base wafer bonding surface side, polishing the polycrystalline silicon layer surface, forming the insulator film on the bonding surface of the bond wafer, bonding the polished surface of the base wafer polycrystalline silicon layer and bond wafer via the insulator film; thinning the bonded bond wafer to form an SOI layer; wherein, in the step of depositing the polycrystalline silicon layer, a wafer having a chemically etched surface as base wafer; chemically etched surface is subjected to primary polishing followed by depositing the polycrystalline silicon layer on surface subjected to the primary polishing, and in the step polishing the polycrystalline silicon layer surface, which is subjected to secondary polishing or secondary and finish polishing.

Method for manufacturing a bonded SOI wafer

A method for producing a SOI wafer that includes implanting at least one type of gas ion selected from a hydrogen ion and a rare gas ion from a surface of a bond wafer formed of a silicon single crystal to form an ion implanted layer, bonding the ion-implanted surface of the bond wafer to a surface of a base wafer formed of a silicon single crystal through a silicon oxide film formed on the base wafer surface, delaminating the bond wafer at the ion implanted layer by performing delamination heat treatment to fabricate a SOI wafer having a buried oxide film layer and a SOI layer on the base wafer, and performing flattening heat treatment on the SOI wafer in an atmosphere containing argon gas.

Method for producing SOI wafer

Method of producing bonded wafer including thin film on base wafer, including: implanting at least one gas ion selected from hydrogen ion and rare gas ion into bond wafer from surface of bond wafer to form layer of implanted ion; bonding surface from which ion is implanted into bond wafer and surface of base wafer directly or through insulator film; and then performing heat treatment to separate part of bond wafer along layer of implanted ion, wherein before bond wafer and base wafer are bonded, thickness of bond wafer and base wafer is measured, and combination of bond wafer and base wafer is selected such that difference in thickness between the wafers is less than 5 &#x3bc;m, and selected bond and base wafers are bonded. This method can inhibit variation in thickness in marble pattern that occurs in thin film and produce bonded wafer including thin film with uniform thickness.

Method of producing bonded wafer with uniform thickness distribution

The present invention is a method for manufacturing a bonded SOI wafer including: performing a thermal oxidation treatment including at least one of a thermal oxidation during temperature-rising and a thermal oxidation during temperature-falling with the use of a batch type heat treatment furnace, thereby forming a silicon oxide film in such a way that the oxide film buried in the delaminated bonded SOI wafer has a concentric oxide film thickness distribution, and subjecting the bonded SOI wafer after delaminating a bond wafer to a reducing heat treatment to make a film thickness range of the buried oxide film being smaller than a film thickness range before the reducing heat treatment. This provides a method for manufacturing a bonded SOI wafer which can suppress a variation of a radial distribution of a buried oxide film thickness caused by a reducing heat treatment performed after delaminating the SOI layer.

A method for manufacturing a bonded wafer, includes: ion-implanting a gas ion such as a hydrogen ion from a surface of a bond wafer, thereby forming an ion-implanted layer; bonding the bond wafer and a base wafer; producing a bonded wafer having a thin-film on the base wafer by delaminating the bond wafer along the ion-implanted layer; and performing an RTA treatment on the bonded wafer in a hydrogen gas-containing atmosphere; wherein a protective film is formed onto the surface of the thin-film in a heat treatment furnace in the course of temperature-falling from the maximum temperature of the RTA treatment before the bonded wafer is taken out from the heat treatment furnace; and then the bonded wafer with the protective film being formed thereon is taken out from the heat treatment furnace, and is then cleaned with a cleaning liquid which can etch the protective film and the thin-film.

Method for manufacturing bonded wafer

The present invention provides a method of manufacturing a bonded wafer, including performing RTA under an atmosphere containing hydrogen on a bonded wafer after separating the bond wafer constituting the bonded wafer, and subsequently performing a sacrificial oxidation process to reduce the thickness of the thin film, wherein the RTA is performed under conditions of a retention start temperature of more than 1150&#xb0; C. and a retention end temperature of 1150&#xb0; C. or less. The invention can inhibit the BMD density from increasing and sufficiently flatten the surface of a thin film when the thin film of the bonded wafer is flattened and thinned by the combination of the RTA and sacrificial oxidation processes.

Method of fabricating SOI wafer by ion implantation

Method for manufacturing a bonded wafer, including implanting at least one gas ion into a bond wafer from a bond wafer surface forming an ion implantation layer, bonding the surface from the ion implantation into bond wafer and base wafer surface, and delaminating the bond wafer part along the ion implantation layer by heat treatment forming a bonded wafer having thin-film on the base wafer, wherein heat treatment is at most 400&#xb0; C. to delaminate bond wafer part along the ion implantation layer, including measuring bond wafer thicknesses and base wafer, selecting a combination of bond and base wafers so difference between both wafers thicknesses is 5 &#x3bc;m or more before bonding the bond and base wafers. Inhibition of film thickness unevenness with marble pattern caused in thin-film when a bonded wafer is manufactured by ion implantation delamination method, and can manufacture a bonded wafer having thin-film with high thickness uniformity.

A method for manufacturing a SOI wafer, including a step of performing a thickness reducing adjustment to a SOI layer of the SOI wafer by carrying out a sacrificial oxidation to the SOI wafer for effecting thermal oxidation to a surface of the SOI layer and removing a formed thermal oxide film, wherein, when the thermal oxidation in the sacrificial oxidation treatment is carried out with the use of a batch processing heat treatment furnace during the rising of a temperature and/or the falling of a temperature, a substantially concentric oxide film thickness distribution is formed on the surface of the SOI layer. The result is a method for manufacturing a SOI wafer that enables manufacturing a SOI wafer that has improved radial film thickness distribution with good productivity by performing the sacrificial oxidation treatment for forming a substantially concentric oxide film and removing the formed thermal oxide film.

Method for manufacturing SOI wafer

The present invention is directed to a method for manufacturing an SOI wafer in which the bonded SOI wafer after the delamination by the ion implantation delamination method is subjected to a rapid thermal oxidation process such that an oxide film is formed on a surface of the SOI layer, the oxide film is removed, the bonded SOI wafer is then subjected to a flattening heat treatment to flatten the surface of the SOI layer, the flattening heat treatment causing migration of silicon atoms of the surface of the SOI layer, and the bonded SOI wafer is then subjected to a sacrificial oxidation process to adjust a film thickness of the SOI layer. The method enables efficient manufacture of a high quality SOI wafer having an SOI layer with sufficiently reduced surface roughness of the SOI layer surface and fewer deep pits in the SOI layer surface.

According to the present invention, there is provided a method for manufacturing an SOI wafer having the step of performing a first sacrificial oxidation treatment on the aforementioned bonded SOI wafer in which the delamination has been performed after a first RTA treatment has been performed thereon and then performing a second sacrificial oxidation treatment thereon after a second RTA treatment has been performed thereon, wherein the first and second RTA treatments are performed under a hydrogen gas containing atmosphere and at a temperature of 1100&#xb0; C. or more, wherein after a thermal oxide film has been formed on the aforementioned SOI layer front surface by performing only thermal oxidation by a batch type heat treating furnace at a temperature of 900&#xb0; C. or more and 1000&#xb0; C. or less in the first and second sacrificial oxidation treatments, a treatment for removing the thermal oxide film is performed.

A silicon epitaxial wafer having a silicon epitaxial layer grown by vapor phase epitaxy on a main surface of a silicon single crystal substrate, wherein the main surface of the silicon single crystal substrate is tilted with respect to a [100] axis at an angle &#x3b8; in a [011] direction or a [0-1-1] direction from a (100) plane and at an angle &#x3c6; in a [01-1] direction or a [0-11] direction from the (100) plane, the angle &#x3b8; and the angle &#x3c6; are less than ten minutes, and a dopant concentration of the silicon epitaxial layer is equal to or more than 1&#xd7;10/cm. Even when an epitaxial layer having a dopant concentration of 1&#xd7;10/cmor more is formed on the main surface of the silicon single crystal substrate, stripe-shaped surface irregularities on the epitaxial layer are inhibited.

Silicon epitaxial wafer, method for manufacturing the same, bonded SOI wafer and method for manufacturing the same

The present invention is a method for manufacturing a bonded wafer including at least the steps of: forming an ion-implanted layer inside a bond wafer; bringing the ion-implanted surface of the bond wafer into close contact with a surface of a base wafer directly or through a silicon oxide film; and performing heat treatment for delaminating the bond wafer at the ion-implanted layer, wherein the heat treatment step for delaminating includes performing a pre-annealing at a temperature of less than 500&#xb0; C. and thereafter performing a delamination heat treatment at a temperature of 500&#xb0; C. or more, and the pre-annealing is performed at least by a heat treatment at a first temperature and a subsequent heat treatment at a second temperature higher than the first temperature. As a result, there is provided a method for manufacturing a bonded wafer having high quality, for example, mainly the reduction of defects, by forming a high bonding strength state at a lower temperature than the temperature at which the delamination is caused, in the manufacture of the bonded wafer by the Smart Cut method (registered trademark).

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Takasaki, Japan

Norihiro Kobayashi