Sumco Corporation

Kabushiki Kaisha Toshiba

Bong-Gyun Ko

Takeshi Hamamoto

Toshiaki Ono

Takashi Yamada

Tetsuya Nakai

Yoshiro Aoki

Yoshio Murakami

Kousuke Takata

A method of reducing warp imparted to a silicon wafer having a (110) plane orientation and a <111> notch orientation by anisotropic film stress of a multilayer film that is to be formed on a surface of the silicon wafer, that includes forming the multilayer film on a surface of the silicon wafer in an orientation so that a direction in which the warp of the wafer will be greatest coincides with a direction in which Young's modulus of a crystal orientation of the silicon wafer is greatest. Also, a method of reducing warp imparted to a silicon wafer having a (111) plane orientation by isotropic film stress of a multilayer film to be formed on a surface of the silicon wafer, that includes, prior to forming the multilayer film, causing the silicon wafer to have an oxygen concentration of 8.0×10atoms/cmor more (ASTM F-121, 1979).

Method of reducing wrap imparted to silicon wafer by semiconductor layers

Provided is a method capable of predicting the warpage caused when a silicon wafer is subjected to heat treatment taking into account the effect of oxygen and a method of producing a silicon wafer. The method includes: determining the mobile dislocation density, the stress, and the time evolution of the strain of the silicon wafer being subjected to heat treatment from the rate of change in the strain and the rate of change in the mobile dislocation density; and determining the magnitude of plastic deformation of the silicon wafer as a warpage. The mobile dislocation density Nat the start of the heat treatment is given as:&#xd7;(&#x394;)&#x2003;&#x2003;(1),

Method of predicting warpage of silicon wafer and method of producing silicon wafer

Provided is a silicon wafer manufacturing method capable of reducing the warpage of the wafer occurring during a device process and allowing the subsequent processes, which have been suffered from problems due to severe warping of the wafer, to be carried out without problems and its manufacturing method. A silicon wafer manufacturing method according to the present invention is provided with calculating a target thickness of the silicon wafer required for ensuring a warpage reduction amount of a silicon wafer warped during a device process from a relationship between an amount of warpage of a silicon wafer and a thickness thereof occurring due to application of the same film stress to a plurality of silicon wafers having mutually different thicknesses; and processing a silicon single crystal ingot to thereby manufacture silicon wafers having the target thickness.

Silicon wafer manufacturing method

At oxygen ion implanting steps in manufacture of a SIMOX wafer, a path is formed inside or on a back surface of wafer holding means, and oxygen ions are implanted while heating an outer peripheral portion of the wafer that is in contact with the wafer holding means by flowing a heated fluid through this path. An in-plane temperature of a wafer held at the time of ion implantation is prevented from becoming uneven, and in-plane film thicknesses of both an SOI layer and a BOX layer are uniformed.

Method for manufacturing SIMOX wafer

A SIMOX wafer is produced by implanting an oxygen ion, in which a hydrogen ion is implanted at a dose of 10-10/cmbefore or after the step of the oxygen ion implantation.

Method of producing SIMOX wafer

To easily and accurately flush a substrate surface serving an SOI area with a substrate surface serving as a bulk area, make a buried oxide film, and prevent an oxide film from being exposed on substrate surface. After partially forming a mask oxide filmon the surface of a substrateconstituted of single crystal silicon, oxygen ionsare implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form an buried oxide filminside the substrate. Further included is a step of forming a predetermined-depth concave portiondeeper than substrate surfaceserving as a bulk area on which the mask oxide film is formed on the substrate surfaceserving as an SOI area by forming a thermally grown oxide filmon the substrate surfaceserving as an SOI area on which the mask oxide film is not formed between the step of forming the mask oxide film and the step of implanting oxygen ions.

Method of manufacturing SOI substrate

A MLD-SIMOX wafer is obtained by forming a first ion-implanted layer in a silicon wafer; forming a second ion-implanted layer that is in an amorphous state; and subjecting the wafer to a high-temperature heat treatment to maintain the wafer in an atmosphere containing oxygen at a temperature that is not lower than 1300&#xb0; C. but lower than a silicon melting point to change the first and the second ion-implanted layers into a BOX layer, wherein the dose amount for the first ion-implanted layer is 1.25 to 1.5&#xd7;10atoms/cm, the dose amount for the second ion-implanted layer is 1.0&#xd7;10to 1&#xd7;10atoms/cm, the wafer is preheated to a temperature of 50&#xb0; C. to 200&#xb0; C. before forming the second ion-implanted layer, and the second ion-implanted layer is formed in a state where it is continuously heated to a preheating temperature.

To easily and accurately flush a substrate surface serving an SOI area with a substrate surface serving as a bulk area, make a buried oxide film, and prevent an oxide film from being exposed on substrate surface. After partially forming a mask oxide filmon the surface of a substrateconstituted of single crystal silicon, oxygen ionsare implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form a buried oxide filminside the substrate. Further included is a step of forming a predetermined-depth concave portiondeeper than substrate surfaceserving as a bulk area on which the mask oxide film is formed on the substrate surfaceserving as an SOI area by forming a thermally grown oxide filmon the substrate surfacea serving as an SOI area on which the mask oxide film is not formed between the step of forming the mask oxide film and the step of implanting oxygen ions.

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Tokyo, Japan

Bong-Gyun Ko