Method and device for producing a SiC solid material

An SiC production facility,

• at least comprising
• multiple SiC production reactors,
• wherein each SiC production reactor at least comprises
• a process chamber,
• a gas inlet unit for feeding a feed-medium or multiple feed-mediums into the process chamber
• a SiC growth substrate arranged inside the process chamber,
• a first power connection and a second power connection,
• wherein the SiC growth substrate is coupled between the first power connection and the second power connection for heating the SiC growth substrate due to resistant heating, and
• a gas outlet unit for outputting vent gas
• a vent gas recycling unit,
• wherein the vent gas recycling unit is connected to the gas outlet units of the SiC production reactors,
• wherein the vent gas recycling unit comprises
• a separator unit for separating the vent gas into a first fluid and into a second fluid,
• wherein the first fluid is a liquid and wherein the second fluid is a gas.

A PVT source material production method for the production of a PVT source material consisting of SiC, at least comprising the steps of:

• Providing a source medium inside a process chamber,
• wherein a gas outlet unit for outputting vent gas out of the process chamber and a vent gas recycling unit are provided,
• wherein the vent gas recycling unit is connected to the gas outlet unit,
• wherein the vent gas recycling unit comprises
• a separator unit for separating the vent gas into a first fluid and into a second fluid, wherein the first fluid is a liquid and wherein the second fluid is a gas,
• wherein the vent gas recycling unit comprises a further separator unit for separating the first fluid into at least two parts, wherein the two parts are
• a mixture of chlorosilanes and
• a mixture of HCl, H2 and at least one C-bearing molecule,
• or alternatively into at least three parts, wherein the three parts are
• a mixture of chlorosilanes
• HCl and
• a mixture of H2 and at least one C-bearing molecule,
• wherein the first storage and/or conducting element connects the separator unit with the further separator unit, wherein the further separator unit is coupled with a mixture or chlorosilanes storage and/or conducting element,
• wherein the mixture of chlorosilanes storage and/or conducting element forms a section of a mixture of chlorosilanes mass flux path for conducting the mixture of chlorosilanes into the process chamber
• Feeding the mixture of chlorosilanes via the mixture of chlorosilanes mass flux path into the process chamber for providing at least one part of the source medium,
• Electrically energizing at least one SiC growth substrate, disposed in the process chamber to heat the SiC growth substrate/s to a temperature in the range between 1300 °C and 2000 °C,
• wherein each SiC growth substrate comprises a first power connection and a second power connection,
• wherein the first power connections are first metal electrodes and wherein the second power connections are second metal electrodes,
• and
• Setting a deposition rate for removing Si and C from the source medium and for depositing the removed Si and C as SiC on the SiC growth substrate/s.

A method for the production of at least one SiC crystal

• comprising the steps:
• providing a PVT reactor for the production of at least one SiC crystal,
• wherein the PVT reactor comprises
• a furnace unit,
• wherein the furnace unit comprises a furnace housing with an outer surface and an inner surface,
• at least one crucible unit
• wherein the crucible unit is arranged inside the furnace housing,
• wherein the crucible unit comprises a crucible housing,
• wherein the crucible housing has an outer surface and an inner surface, wherein the inner surface at least partially defines a crucible volume,
• wherein a receiving space for receiving a source material is arranged or formed inside the crucible volume,
• wherein a seed holder unit for holding a defined seed wafer is arranged inside the crucible volume, wherein the seed wafer holder holds a seed wafer,
• wherein the furnace housing inner wall and the crucible housing outer wall define a furnace volume,
• at least one heating unit for heating the source material,
• wherein the receiving space for receiving the source material is at least in parts arranged above the heating unit and below the seed holder unit,
• adding PVT source material as source material into the receiving space,
• sublimating the added PVT source material and
• depositing the sublimated SiC on the seed wafer and thereby forming the at least one or exactly one SiC crystal,
• wherein
• the PVT reactor comprises a crucible gas flow unit, wherein the crucible gas flow unit comprises a crucible gas inlet tube for conducting gas into the crucible volume, wherein the crucible gas inlet tube is arranged in vertical direction below the receiving space
• and the step
• conducting gas via the crucible gas flow unit into the crucible housing.