Wacker Siltronic Gesellschaft Fur Halbleitermaterialien Ag

Wacker-Chemitronic Gesellschaft Fur Elektronik-Grundstoffe Mbh

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Wacker Chemitronic Gesellschaft

Wacker Siltronik Gesellschaft Fur Halbleitermaterialien Ag

Wilfried Von Ammon

Erich Dornberger

Hans Olkrug

Erich Tomzig

Franz Segieth

Reinhold Wahlich

Paul Fuchs

Ulrich Lambert

Werner Zulehner

Theresia Bauer

Peter Krottenthaler

Alfred Buchner

Dieter Graef

Yuri Gelfgat

Heinz Klinger

Leonid Gorbunov

Hans Oelkrug

Alfred Pardubitzki

Herbert Weidner

Heinz Winterer

Peter Dreier

Rasso Ostermeir

Herber Weidner

Peter Gerlach

Ludwig Thanner

Yu M Gelfgat

Franz Wasmeier

Vincent Wertz

Francois Dupret

Nathalie Van Den Bogaert

J&uuml;rgen Hage

Gunther Obermeier

A semiconductor wafer has a front side , a back side , a top layer , a bottom layer , an upper inner layer lying beneath the top layer , an lower inner layer lying above the bottom layer , a central region between the layers and , and an uneven distribution of crystal lattice defects. The crystal lattice defects are substitutionally or interstitially included nitrogen or vacancies.

Semiconductor wafer with crystal lattice defects, and process for producing this wafer

Device for pulling a silicon single crystal 1 includes an element 5 which annularly surrounds the single crystal growing at a crystallization boundary; and the element has a face 6 directed at the single crystal. The element surrounds the single crystal substantially level with the crystallization boundary 2 and has the property of reflecting heat radiation radiated by the single crystal and the similar melt or of generating and radiating heat radiation back to the lower part of the crystal close to the crystallization boundary. There is also a method for pulling a silicon single crystal, in which the single crystal is thermally affected using the element surrounding it.

Device and method for pulling a single crystal

A process for producing a silicon single crystal by the Czochralski method, utilizes a heater which is intended for heating a silicon-filled crucible and is arranged below the crucible. The process has energy delivered to the melt at least some of the time inductively using a coiled heater arranged under the crucible. The heater is in the form of a wound coil.

Process for producing a silicon single crystal, and heater for carrying

A method and an apparatus for pulling a silicon monocrystal from a melt iudes the pulling of a conical portion in each case at the beginning and at the end of the monocrystal and the pulling of a cylindrical portion between the conical portions. In this method, the surface of the conical portion at the beginning of the monocrystal is shielded by a shielding means spaced apart from the monocrystal.

Method and apparatus for pulling a monocrystal

A process for the growth of a single crystal from semiconductor material by the Czochralski method, in which the melt is subjected to the influence of a magnetic field during the crystal growth and the magnetic field is generated by superposing a static magnetic field and an alternating magnetic field. An apparatus for carrying out the process, has a magnetic means which comprises two coils which are arranged around a crucible, one coil generating a static magnetic field and the other coil generating an alternating magnetic field.

Process and apparatus for the growth of single crystals

A method for producing a silicon monocrystal has a growing monocrystal kept for a specified dwell time in the specified temperature range of from 850.degree. C. to 1100.degree. C. This dwell time for the growing monocrystal in the chosen temperature range is either greater than 250 min or less than 80 min. A device and a method, in which the cooling rate of the growing monocrystal is to be influenced, has a heat shield which is subdivided into adjacent annular zones between a lower rim and an upper rim. These adjacent zones differ in regard to each's thermal conduction and transparency to heat radiation.

Method and device for producing monocrystals

A process for producing silicon wafers with low defect density is one wherein a) a silicon single crystal having an oxygen doping concentration of at least 4*10.sup.17 /cm.sup.3 is produced by molten material being solidified to form a single crystal and is then cooled, and the holding time of the single crystal during cooling in the temperature range of from 850.degree. C. to 1100.degree. C. is less than 80 minutes; b) the single crystal is processed to form silicon wafers; and c) the silicon wafers are annealed at a temperature of at least 1000.degree. C. for at least one hour. Also, it is possible to prepare a silicon single crystal based upon having an oxygen doping concentration of at least 4*10.sup.17 /cm.sup.3 and a nitrogen doping concentration of at least 1*10.sup.14 /cm.sup.3 for (a) above.

Process for producing silicon semiconductor wafers with low defect

A process and an apparatus control the growth of a crystal, which growth is governed by a set of measurable and non-measurable variables. The process includes establishing an on-line simulation software working with a reduced number of variables, the reduction of variables being performed by using a projection algorithm; speeding up the on-line simulation software by generating data banks in which values of off-line precalculated variables are stored; tuning the on-line simulation software by adjusting the results predicted by on-line simulations to the results obtained by off-line simulations and by measurements; and establishing a control loop and controlling at least one of the variables in real time, the control loop using the speeded up and tuned on-line simulation software as an on-line observer.

Process for controlling the growth of a crystal

Method for pulling a monocrystal

A method and a device is provided for determining the diameter of a monocrystal growing at a crystallization boundary during the pulling of the monocrystal from a melt. The method includes imaging a part of the crystallization boundary on at least one mirror, observing the mirror image and determining the diameter of the monocrystal from the observed relative position of the crystallization boundary on the mirror image.

Method for determining the diameter of a growing monocrystal

Apparatus for producing a single crystal of semiconductor material in accance with the Czochralski method, has a cooling means which cools the growing single crystal and is constructed in two parts, The first is an upper part duct system through which a liquid coolant flows. The second is a lower part which is a heat-conducting cooling body.

Apparatus for producing a single crystal

A method for pulling a silicon single crystal has the single crystal being pulled at a speed defined as maximum pulling speed in the vertical direction with respect to a silicon melt held in a crucible. The value of the maximum pulling speed is approximately proportional to the axial temperature gradient in the growing single crystal.

Method for pulling a silicon single crystal

Silicon ingots, in particular, with diameters of approximately 75 mm and greater, can be produced by zone pulling with an oxygen content comparable to crucible-pulled material if a flat quartz element is brought into contact with the molten cap during the pulling operation. A quartz ring which is arranged concentrically beneath the induction heating coil and can be lowered from a rest position into its working position on the molten cap is suitable as a flat element. The ingot material obtained in this manner and also the silicon wafers produced therefrom combine the purity advantages of zone-pulled silicon with the beneficial gettering and hardening action of the incorporated oxygen which otherwise distinguishes only crucible-pulled silicon.

Process and apparatus for producing silicon ingots having high oxygen

An induction heating coil for a zone pulling of semiconductor rods assures the disturbance-free performance of the pulling process even at the high power densities required for large rod diameters (approximately 10 to 12 cm). According to the invention, the arc-over paths between surfaces in the region of the coil slot, which are at differing potentials, are covered by one or more movable planar structures of temperature-stable insulating material which are introduced into the coil slot.

Growing community of inventors

Burghausen, Germany

Wilfried Von Ammon