Susceptor system
The present invention relates to a susceptor system for an apparatus of the type adapted to treat substrates and/or wafers; the susceptor system is provided with a cavity ( 1 ) which acts as a chamber for the treatment of the substrates and/or wafers and which extends in a longitudinal direction and is delimited by an upper wall ( 2 ), by a lower wall ( 3 ), by a right-hand side wall ( 4 ), and by a left-hand side wall ( 5 ); the upper wall ( 2 ) is constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction; the lower wall ( 3 ) is constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction; the right-hand side wall ( 4 ) is constituted by at least one piece of inert, refractory and electrically insulating material; the left-hand side wall ( 5 ) is constituted by at least one piece of inert, refractory and electrically insulating material; the piece of the upper wall ( 2 ) is thus electrically well insulated from the piece of the lower wall ( 3 ).
1. A susceptor system for an apparatus of the type adapted to treat substrates and/or wafers, the susceptor system being provided with a cavity ( 1 ) which acts as a chamber for the treatment of the substrates and/or wafers and which extends in a longitudinal direction and is delimited by an upper wall ( 2 ), by a lower wall ( 3 ), by a right-hand side wall ( 4 ), and by a left-hand side wall ( 5 ), the upper wall ( 2 ) being constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction, the lower wall ( 3 ) being constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction, the right-hand side wall ( 4 ) being made in its entirety by at least one piece of inert, refractory material and preventing conduction of electrical current there through, the left-hand side wall ( 5 ) being made in its entirety by at least one piece of inert, refractory material and preventing conduction of electrical current there through, the right-hand side wall ( 4 ) and the left-hand side wall ( 5 ) each separating the upper wall ( 2 ) from the lower wall ( 3 ) SO that the or each piece of the upper wall ( 2 ) is electrically insulated from the or each piece of the lower wall ( 3 ), the walls ( 2 , 3 , 4 , 5 ) being included in the susceptor system.
2. A susceptor system according to claim 1 in which each of the right-hand wall ( 4 ) and the left-hand wall ( 5 ) is constituted by a single piece.
3. A susceptor system according to claim 1 in which the or each piece of the upper wall ( 2 ) and of the lower wall ( 3 ) is made of graphite or similar electrically conducting material and is coated with a layer of silicon, tantalum, niobium, or boron carbide, or of silicon, boron, or aluminum nitride, or of similar inert and refractory material, at least in the areas adjacent the cavity ( 1 ).
4. A susceptor system according to claim 1 in which the external shape of the cross-section of the susceptor system is substantially uniform in the longitudinal direction and is substantially circular or elliptical.
5. A susceptor system according to claim 1 in which the shape of the cross-section of the cavity ( 1 ) is substantially uniform in the longitudinal direction.
6. A susceptor system according to claim 1 in which the average width of the cavity ( 1 ) is at least three times, more preferably at least five times, the average height of the cavity ( 1 ).
7. A susceptor system according to claim 1 in which the pieces of the side walls ( 4 , 5 ) have cross-sections of substantially rectangular or trapezoidal shape.
8. A susceptor system according to claim 1 in which the piece of the upper wall ( 2 ) and/or the piece of the lower wall ( 3 ) have cross-sections having the external shape substantially of a segment of a circle or a segment of an ellipse.
9. A susceptor system according to claim 1 in which the piece of the upper wall ( 2 ) and/or the piece of the lower wall ( 3 ) have grooves ( 22 , 32 ) and/or ribs in the longitudinal direction for joining with the pieces of the side walls ( 4 , 5 ).
10. A susceptor system according to claim 1 in which the piece of the upper wall ( 2 ) and/or the piece of the lower wall ( 3 ) is hollow so as to have at least one hole ( 21 , 31 ), preferably a through-hole, which extends in the longitudinal direction.
11. A susceptor system according to claim 1 comprising a slide ( 6 ) mounted inside the cavity ( 1 ) and suitable for supporting at least one substrate or at least one wafer, the slide ( 6 ) being slidable in guided manner in the longitudinal direction.
12. A susceptor system according to claim 11 in which the lower wall ( 3 ) has a guide ( 33 ) which is suitable for receiving the slide ( 6 ) and which extends in the longitudinal direction so that the slide ( 6 ) can slide along the guide ( 33 ).
13. A susceptor system according to claim 11 in which the slide ( 6 ) comprises at least one disc ( 61 ) suitable for supporting at least one substrate or at least one wafer, and is provided with a recess ( 62 ) suitable for housing the disc ( 61 ) rotatably.
14. Apparatus of the type adapted to treat substrates and/or wafers, characterized in that it comprises at least one susceptor system ( 2 , 3 , 4 , 5 ) according to claim 1 .
15. Apparatus according to claim 14 , comprising a first refractory and thermally insulating structure ( 7 ) which surrounds the susceptor system ( 2 , 3 , 4 , 5 ) and is constituted substantially by a tube of high-porosity graphite or similar material and which extends in the longitudinal direction.
16. Apparatus according to claim 15 in which the first structure ( 7 ) is divided, in the longitudinal direction, into two half-tubes ( 71 , 72 ) and the first structure ( 7 ) further comprises two elements ( 73 ) of refractory, thermally insulating and preferably electrically insulating material which extend in the longitudinal direction and are disposed between the two half-tubes ( 71 , 72 ).
17. Apparatus according to claim 15 comprising a second, hermetic structure ( 8 ) suitable for surrounding the first structure ( 7 ).
18. Apparatus according to claim 14 comprising electrical conduction means ( 9 ) which are suitable for heating the susceptor system by electromagnetic induction and which are wound around the first structure ( 7 ) or around the second structure ( 8 ).
19. Apparatus according to any one of claims 14 to 18 , comprising means for causing at Icast one gas-flow to flow in at least one through-hole ( 21 , 31 ) of the susceptor system.
20. Apparatus according to claim 14 characterized in that it is a reactor for the epitaxial growth of silicon carbide or similar material on substrates.
21. Apparatus according to claim 14 characterized in that it is an apparatus for the high-temperature thermal treatment of wafers.
22. A susceptor system for an apparatus of the type adapted to treat substrates and/or wafers, the susceptor system being provided with a cavity ( 1 ) which acts as a chamber for the treatment of the substrates and/or wafers and which extends in a longitudinal direction and is delimited by an upper wall ( 2 ), by a lower wall ( 3 ), by a right-hand side wall ( 4 ), and by a left-hand side wall ( 5 ), the upper wall ( 2 ) being constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction, the lower wall ( 3 ) being constituted by at least one piece of electrically conducting material suitable for being heated by electromagnetic induction, the right-hand side wall ( 4 ) being made in its entirety by at least one piece of inert, refractory material and preventing conduction of electrical current there through, the left-hand side wall ( 5 ) being made in its entirety by at least one piece of inert, refractory material and preventing conduction of electrical current there through, the right-hand side wall ( 4 ) and left- hand side wall ( 5 ) each separating the upper wall ( 2 ) from the lower wall ( 3 ) so that the or each piece of the upper wall ( 2 ) is electrically insulated from the or each piece of the lower wall ( 3 ), the walls ( 2 , 3 , 4 , 5 ) being included in the susceptor system, the susceptor system further comprising a first refractory and thermally insulating structure ( 7 ) which surrounds the susceptor system ( 2 , 3 , 4 , 5 ) and which extends in the longitudinal direction.
23. A susceptor system according to claim 1 in which the or each piece of the side walls ( 4 , 5 ) is made of one or more of silicon carbide and boron nitride.
24. A susceptor system according to claim 22 in which the or each piece of the side walls ( 4 , 5 ) is made of one or more of silicon carbide and boron nitride.
25. A susceptor system according to claim 1 in which each of the walls ( 2 , 3 , 4 , 5 ) is constituted by a single piece.
26. A susceptor system according to claim 22 in which each of the right-hand wall ( 4 ) and the left-hand wall ( 5 ) is constituted by a single piece.
27. A susceptor system according to claim 22 in which each of the walls ( 2 , 3 , 4 , 5 ) is constituted by a single piece.