Siemens Aktiengesellschaft

Rene Stein

Harald Kuhn

Roland Rupp

Johannes Voelkl

Johannes V&ouml;lkl

Georg Wittmann

Wolfgang Zintl

A method for the sublimation growth of an SiC single crystal, involving heating up under growth pressure, is described. In the method for the sublimation growth of the SiC single crystal, a crucible holding a stock of solid SiC and an SiC seed crystal, onto which the SiC single crystal grows, is evacuated during a starting phase which precedes the actual growth phase and is then filled with an inert gas, until a growth pressure is reached in the crucible. Moreover, the crucible is initially heated to an intermediate temperature and then, in a heat-up phase, is heated to a growth temperature at a heat-up rate of at most 20&deg; C./min. As a result, controlled seeding on the SiC seed crystal is achieved even during the heat-up phase.

Method for the sublimation growth of an SiC single crystal, involving heating under growth pressure

A device for the sublimation growth of an SiC single crystal, with foil-lined crucible. The device for producing an SiC single crystal includes a crucible with a crucible inner zone. Inside this zone, there is a storage area for storing a stock of solid SiC and a crystal area in which an SiC single crystal grows onto an SiC seed crystal. A heater device is arranged outside the crucible. On a side that faces the crucible inner zone, the crucible is lined with a foil of tantalum, tungsten, niobium, molybdenum, rhenium, iridium, ruthenium, hafnium or zirconium. As a result, the crucible is sealed and a reaction between the aggressive components of the SiC gas phase and the crucible wall is prevented.

Device having a foil-lined crucible for the sublimation growth of an SiC single crystal

A seed crystal holder holds a SiC seed crystal while a SiC bulk single crystal is grown on the front surface of the seed crystal. The holder includes a back surface body with a bearing surface for bearing against a back surface of the SiC seed crystal. The holder includes a lateral mount for receiving the back surface body and the SiC seed crystal. The lateral mount has a projection located on an end facing the SiC seed crystal. The SiC seed crystal rests on the projection.

Seed crystal holder with lateral mount for an SiC seed crystal

An &agr;-SiC bulk single crystal is formed from an SiC gas phase by deposition of SiC on an SiC seed crystal. To enable an SiC bulk single crystal of the 15R type to be grown reproducibly and without restricting the seed crystal, the deposition takes place under a uniaxial tensile strength which includes a predetermined angle with the &lsqb;0001&rsqb; axis of the bulk single crystal, so that a rhombohedral crystal is formed.

Method for growing an &agr;-SiC bulk single crystal

A method is described for growing at least one silicon carbide (SiC) single crystal by sublimation of a SiC source material. Silicon, carbon and a SiC seed crystal are introduced into a growing chamber. Then, the SiC source material is produced from the silicon and the carbon in a synthesis step that takes place before the actual growing. The growing of the SiC single crystal is then carried out immediately after the synthesis step. The carbon used is a C powder with a mean grain diameter of greater than 10 &mgr;m.

Method for growing SiC single crystals

A device for producing a silicon carbide (SiC) single crystal contains a crucible having a storage region for holding a stock of solid SiC and having a crystal region for holding a SiC seed crystal. An insert made from glassy carbon is disposed in the crucible. In the method, solid SiC is sublimed as a result of the stock being heated and SiC in the gas phase is generated, which is conveyed to the SiC seed crystal, on which it grows as an SiC single crystal. A heat flux is controlled by an insert made from glassy carbon.

Device and method for producing at least one SiC single crystal

A seed crystal assembly for producing monocrystals and a method for producing SiC monocrystals or monocrystalline SiC layers include a seed crystal with a surface having a first partial region intended as a crystallization surface for a monocrystal grown out of a gas phase and a second partial region with a coating that is chemically resistant to the seed crystal and to the gas phase and does not melt at the growth temperatures. As a result, thermal degradation of the seed crystal is avoided and the quality of the monocrystals which are produced is increased.

Seed crystal for producing monocrystals and method for producing SiC

A method for producing cubic SiC monocrystals includes dissolving SiC powder or other starting material in a solvent at high overpressures and growing the monocrystals on a seed crystal.

Method for producing silicon carbide monocrystals

Method of producing boron-doped monocrystalline silicon carbide

A MISFET (metal-insulator semiconductor field-effect transistor) may be used for application at temperatures above 200.degree. C. In particular, leakage currents between the gate electrode (6) and the drain (8) are kept at a low level, and a considerable rate of rise in its control characteristic is achieved. An insulating layer (4) of diamond is arranged between the gate electrode (6) and a semiconductor (2) having a larger energy gap than silicon (Si).

Metal-insulator semiconductor field-effect transistor

The invention provides an improved method for polish-etching of silicon carbide, which is arranged in series with an electrolyte and a metallic counter-electrode in a current circuit with an adjustable direct voltage, wherein an alkaline solution is used as the electrolyte, preferably in a high concentration and at great current density. In this way, uniform removal of the material and an even surface are obtained.

Method for electrolytic etching of silicon carbide

Single crystals of silicon carbide (SiC) can be manufactured by subliming and partially decomposing a base material of crystalline silicon carbide powder and by growing the single crystals from seed crystals. According to the present invention, an excess of silicon is added to the silicon carbide base material. Using this technique, high purity, single-crystal silicon carbide is obtained.

Growing community of inventors

Roettenbach, Germany

Rene Stein