Abstract: 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 8.0×1017 atoms/cm3 or more (ASTM F-121, 1979).

Abstract: 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 Ni at the start of the heat treatment is given as: Ni=A×(?Oi×L?Lo)2.5??(1), where A and L0: constants, ?Oi: the concentration of oxygen used by oxygen precipitates in the silicon wafer at the start of the heat treatment, L: the mean size of the oxygen precipitates at the start of the heat treatment.

Abstract: 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.

Abstract: 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 Ni at the start of the heat treatment is given as: Ni=A×(?Oi×L?L0)2.5??(1), where A and L0: constants, ?Oi: the concentration of oxygen used by oxygen precipitates in the silicon wafer at the start of the heat treatment, L: the mean size of the oxygen precipitates at the start of the heat treatment.

Abstract: A silicon wafer is 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 according to the present invention is a silicon wafer in which there is formed a multilayered film constituting a semiconductor device layer on one main surface thereof in a device process, which is warped in a bowl shape due to an isotropic film stress of the multilayered film, and which has a (111) plane orientation.

Abstract: 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.

Abstract: The present invention provides a method of producing a high quality SOI wafer having a thin BOX layer with high productivity. In the method of producing an SOI wafer by performing heat treatment on a silicon wafer after implanting oxygen ions into silicon wafer, first ion implantation is performed on the silicon wafer to a high dose of 2×1017 ions/cm2 to 3×1017 ions/cm2, and then second ion implantation is performed to a low dose of 5×1014 ions/cm2 to 1×1016 ions/cm2. Subsequently, heat treatment is performed in a high oxygen concentration atmosphere at an oxygen partial pressure ratio of 10% to 80%, and then heat treatment is performed in a low oxygen atmosphere at an oxygen partial pressure ratio of less than 10%. After that, heat treatment is performed in a chlorine-containing gas atmosphere by adjusting the oxygen atmosphere to the chlorine-containing gas atmosphere by flowing argon through a chlorine-containing solution.

Abstract: 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.

Abstract: A SIMOX wafer is produced by implanting an oxygen ion, in which a hydrogen ion is implanted at a dose of 1015-1017/cm2 before or after the step of the oxygen ion implantation.

Abstract: 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 film 23 on the surface of a substrate 12 constituted of single crystal silicon, oxygen ions 16 are implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form an buried oxide film 13 inside the substrate. Further included is a step of forming a predetermined-depth concave portion 12c deeper than substrate surface 12b serving as a bulk area on which the mask oxide film is formed on the substrate surface 12a serving as an SOI area by forming a thermally grown oxide film 21 on the substrate surface 12a 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.

Abstract: 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.

Abstract: 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° 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 1.5×1017 atoms/cm2, the dose amount for the second ion-implanted layer is 1.0×1014 to 1×1016 atoms/cm2, the wafer is preheated to a temperature of 50° C. to 200° 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.

Abstract: 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 film 23 on the surface of a substrate 12 constituted of single crystal silicon, oxygen ions 16 are implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form an buried oxide film 13 inside the substrate. Further included is a step of forming a predetermined-depth concave portion 12c deeper than substrate surface 12b serving as a bulk area on which the mask oxide film is formed on the substrate surface 12a serving as an SOI area by forming a thermally grown oxide film 21 on the substrate surface 12a 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.

Abstract: 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 film 23 on the surface of a substrate 12 constituted of single crystal silicon, oxygen ions 16 are implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form a buried oxide film 13 inside the substrate. Further included is a step of forming a predetermined-depth concave portion 12c deeper than substrate surface 12b serving as a bulk area on which the mask oxide film is formed on the substrate surface 12a serving as an SOI area by forming a thermally grown oxide film 21 on the substrate surface 12a 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.

Abstract: 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 film 23 on the surface of a substrate 12 constituted of single crystal silicon, oxygen ions 16 are implanted into the surface of the substrate through the mask oxide film, and the substrate is annealed to form an buried oxide film 13 inside the substrate. Further included is a step of forming a predetermined-depth concave portion 12c deeper than substrate surface 12b serving as a bulk area on which the mask oxide film is formed on the substrate surface 12a serving as an SOI area by forming a thermally grown oxide film 21 on the substrate surface 12a 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.

Abstract: A SIMOX wafer is produced by implanting an oxygen ion, in which a hydrogen ion is implanted at a dose of 1015?1017/cm2 before or after the step of the oxygen ion implantation.

Abstract: There is obtained an MLD-SIMOX wafer having a BOX layer with a thin film thickness that allows a reduction in SOI layer surface roughness and interface roughness of the BOX layer and the SOI layer and an improvement in breakdown voltage. In a method for manufacturing a SIMOX wafer comprising a step of forming a first ion-implanted layer in a silicon wafer; a step of forming a second ion-implanted layer that is in an amorphous state; and a high-temperature heat treatment state of maintaining the wafer in an atmosphere containing oxygen at a temperature that is not lower than 1300° C. but lower than a silicon melting point to change the first and the second ion-implanted layers into a BOX layer, the method is characterized in that a dose amount for the first ion-implanted layer is 1.25 to 1.5×1017 atoms/cm2, a dose amount for the second ion-implanted layer is 1.0×1014 to 1×1016 atoms/cm2, a step of preheating the wafer to a temperature that is not lower than 50° C. but lower than 200° C.