Sumco Corporation

Elpida Memory, Inc.

Longitude Semiconductor S.a.r.l.

Longitude Licensing Limited

Ryota Suewaka

Yoshitaka Nakamura

Noriaki Ikeda

Kenji Komeda

Kaoru Kajiwara

Hideki Tanaka

Kazumi Tanabe

Takahiro Kanehara

Shunji Kuragaki

Provided is a point detect simulator which makes it possible to determine the distribution of point defects in a silicon single crystal in consideration of the thermal stress of the silicon single crystal being grown. A point defect simulatoris a point defect simulator calculating the concentration profiles of vacancies and interstitial silicon during pulling of a silicon single crystal using a convection-diffusion equation reflecting the consideration of thermal stress in the silicon single crystal, and includes an analysis unit used to fit calculation results to experimental results using stress coefficients that are the coefficients of stress terms as a fitting parameter.

Method of producing a silicon single crystal based on concentration profiles of vacancies and interstitial silicon atoms during pulling of a silicon single crystal by the Czochralski process

Provided is a heat shielding member, a single crystal pulling apparatus, and a method of producing a single crystal silicon ingot, which can expand the margin of the crystal pulling rate with which a defect-free single crystal silicon can be obtained. A heat shielding member is provided in a single crystal pulling apparatus, the heat shielding member including a cylindrical tubular portion surrounding an outer circumferential surface of the single crystal silicon ingot; and a ring-shaped projecting portion under the tubular portion. The projecting portion has an upper wall, a bottom wall, and two vertical walls, a heat insulating material with a ring shape is provided in the space surrounded by those walls; and a gap between the vertical wall adjacent to the single crystal silicon ingot and the heat insulating material.

Heat shielding member, single crystal pulling apparatus, and method of producing single crystal silicon ingot

A pulling condition calculation program enables a computer to perform the steps of: setting a plurality of sets of pulling conditions based on solid-liquid interface height and distance between a surface of a silicon melt and a heat shield plate; performing, for each set of the pulling conditions, the steps of: calculating a heat flux (q) (W/m) and a crystal surface temperature (T); defining a reference temperature (Tref) given by an equation (1) below and a geometry of the solid-liquid interface as boundary conditions, recalculating an in-crystal temperature distribution; calculating a mean stress in the monocrystalline silicon; calculating a defect distribution in a pulling direction based on the mean stress and the in-crystal temperature distribution; determining a defect-free region in the pulling direction; and drawing a contour line showing a dimension of the defect-free region on a two-dimensional map defined by the distance and the solid-liquid interface height. 

Silicon single crystal pulling condition calculation program, silicon single crystal hot zone improvement method, and silicon single crystal growing method

A method of manufacturing a single crystal is provided with a raw material melting step of heating a silicon raw material in a quartz crucible using a carbon heater to generate a silicon melt; and a crystal pull-up step of pulling up a single crystal from the silicon melt generated by the raw material melting step, wherein the silicon raw material is heated with the maximum surface temperature of a first part of the heater that is positioned above at least the upper end of the quartz crucible maintained below 1500&#xb0; C. in the raw material melting step.

Method of manufacturing silicon single crystal

A semiconductor device comprises a memory cell region, a peripheral circuit region and a boundary region. In the memory cell region, a concave lower electrode and a foundation layer have a same uppermost surface positioned in a height of H above the plane-A. In the boundary region, one concave lower conductive region and a foundation layer have a same uppermost surface positioned in a height of H above the plane-A.

Growing community of inventors

Tokyo, Japan

Ryota Suewaka