Granted Patent B2

US 12,281,407 · App. 18/028,682 · Granted Apr 22, 2025

Inventors: Robert Ebner (Leonding, AT); Kanaparin Ariyawong (Leonding, AT); Ghassan Barbar (Neunkirchen, DE); Chih-Yung Hsiung (Leonding, AT)

Assignee: EBNER Industrieofenbau GmbH

C30B23/066C30B29/36

Abstract

Claims (17)

1. A method for producing single crystals of silicon carbide with a device comprising a furnace ( 401 ) and a chamber ( 402 ) with a crucible ( 403 ), the chamber ( 402 ) being accommodated in the furnace ( 401 ), wherein a seed crystal and a base material ( 407 ) containing silicon carbide is arranged in the crucible ( 403 ), wherein the base material ( 407 ) contains a mixture of silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ),

wherein the silicon carbide powder ( 411 ) has a grain size with a value from a range of 300 μm to 1000 μm

and the silicon carbide lumps ( 410 ) have a grain size with a value from a range of 1 mm to 10 mm,

and wherein in a first, lower third of the height ( 412 ) of the base material ( 407 ), silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ) are contained in a mix ratio selected from a range between 55% silicon carbide powder ( 411 ) to 45% silicon carbide lumps ( 410 ) and 70% silicon carbide powder ( 411 ) to 30% silicon carbide lumps ( 410 ),

and in a second, middle third of the height ( 412 ) of the base material ( 407 ), silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ) are contained in a mix ratio selected from a range between 40% silicon carbide powder ( 411 ) to 60% silicon carbide lumps ( 410 ) and 55% silicon carbide powder ( 411 ) to 45% silicon carbide lumps ( 410 ),

and in a third, upper third of the height ( 412 ) of the base material ( 407 ), silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ) are contained in a mix ratio selected from a range between 25% silicon carbide powder ( 411 ) to 75% silicon carbide lumps ( 410 ) and 40% silicon carbide powder ( 411 ) to 60% silicon carbide lumps ( 410 ).

2. The method according to claim 1 , wherein, based on a total mass, the base material ( 407 ) contains silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ) in a mix ratio, which is selected from a range between 25 wt. % silicon carbide powder ( 411 ) to 75 wt. % silicon carbide lumps ( 410 ) and 55 wt. % silicon carbide powder ( 411 ) to 45 wt. % silicon carbide lumps ( 410 ).

3. The method according to claim 2 , wherein, based on the total mass, the base material ( 407 ) contains silicon carbide powder ( 411 ) and silicon carbide lumps ( 410 ) in a mix ratio of 40 wt. % silicon carbide powder ( 411 ) to 60 wt. % silicon carbide lumps ( 410 ).

4. The method according to claim 1 , wherein the silicon carbide ( 410 , 411 ) of the base material ( 407 ) has a material purity of greater than 5 N.

5. The method according to claim 1 , wherein the base material ( 407 ) is produced in the form of a pellet ( 413 ).

6. The method according to claim 1 , wherein elementary silicon ( 414 ) is in addition to the silicon carbide added to the base material ( 407 ).

7. The method according to claim 6 , wherein the elementary silicon ( 414 ) is contained in the form of silicon powder ( 411 ).

8. The method according to claim 6 , wherein the elementary silicon ( 414 ) is formed into the base material ( 407 ) in the form of one or multiple stores.

9. The method according to claim 6 , wherein the store with the elementary silicon ( 414 ) is formed into a continuous ring.

10. The method according to claim 6 , wherein the elementary silicon ( 414 ) constitutes a proportion from a range of 5 wt. % to 50 wt. % of a total mass of the base material ( 407 ).

11. The method according to claim 6 , wherein, for this purpose, a storage container ( 417 ) for the powdery, elementary silicon ( 414 ) and a feed line ( 418 ) leading into the crucible ( 403 ) are used.

12. The method according to claim 1 , wherein the crucible ( 403 ) is made from graphite.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (75)