Gas distributor with pre-chambers arranged in planes
View Patent ↗A gas distributor for a CVD or OVPD reactor comprises two or more gas volumes ( 1, 2 ) into each of which opens a feed pipe ( 3, 4 ) for a process gas, each gas volume ( 1, 2 ) being connected to a plurality of corresponding process gas outlets ( 6, 7 ) which open into the bottom ( 5 ) of the gas distributor. In order to increase the homogeneity of the gas composition, the two gas volumes ( 1, 2 ) comprise pre-chambers ( 10, 10′, 11 ) located in a first common plane ( 8 ) and a plurality of gas distribution chambers ( 12, 13 ) each associated with a gas volume are provided in a second plane ( 9 ′) adjacent to the bottom of the gas distributor. The pre-chambers ( 10, 10′, 11 ) and gas distribution chambers ( 12, 13 ) associated with each gas volume ( 1, 2 ) are connected with connection channels ( 14, 15 ).
1. A gas distributor in a CVD or OVPD reactor with two or more gas volumes ( 1 , 2 ), into each of which a supply line ( 3 , 4 ) for a process gas opens out, each gas volume ( 1 , 2 ) being connected to a multiplicity of outlet openings ( 6 , 7 ) for a respective one of the process gases, which open out in a bottom ( 5 ) of the gas distributor, the process gases respectively being first distributed in a radial direction in a first plane ( 8 ), remote from the bottom ( 5 ), and then distributed in a circumferential direction in a second plane ( 9 ′), adjacent to the bottom ( 5 ), and flowing through connecting channels ( 14 , 15 ), which are located in a third plane ( 9 ) disposed between the first plane and the second plane, and a multiplicity of gas distributing chambers ( 12 , 13 ) that are respectively associated with the gas volumes ( 1 , 2 ) and are connected to the outlet openings ( 6 , 7 ) being provided in the second plane ( 9 ′), the gas distributor characterized in that the gas volumes ( 1 , 2 ) have pre-chambers ( 10 , 10 ′, 11 ), at least one pre-chamber of one gas volume and at least one pre-chamber of another gas volume lying at a common elevation in the first plane ( 8 ), the pre-chambers ( 10 , 10 ′, 11 ) of the two gas volumes ( 1 , 2 ) forming continuations like prongs of a comb that extend in the radial direction and engage with one another in a manner of prongs of a comb, the comb-like continuations that lie next to one another in the circumferential direction being separated from one another by a wall ( 17 ).
2. The gas distributor according to claim 1 , further characterized in that pre-chambers ( 10 , 10 ′, 11 ) associated with one of the gas volumes ( 1 , 2 ) are at different radial distances from a center of the gas distributor.
3. The gas distributor according to claim 1 , further characterized in that different ones of the pre-chambers ( 10 ) of a first one of the gas volumes are disposed separately from one another in the circumferential direction.
4. The gas distributor according to claim 1 , further characterized in that each pre-chamber ( 10 , 10 ′, 11 ) is fed by more than one supply line ( 3 , 4 ).
5. The gas distributor according to claim 1 , further characterized in that a first one of the gas volumes is provided for feeding a gaseous, in particular metal-containing or semiconductor-containing, starting material and a second one of the gas volumes is provided for a chemically reactive gas, in particular an oxygen, nitrogen or hydrogen compound.
6. The gas distributor according to claim 1 , further characterized in that the gas distributing chambers ( 12 , 13 ) concentrically surround a center of the gas distributor.
7. The gas distributor according to claim 1 , further characterized in that one or more of the gas distributing chambers ( 12 , 13 ) are connected to a number of the pre-chambers ( 10 , 10 ′, 11 ) by the connecting channels ( 14 , 15 ).
8. The gas distributor according to claim 1 , further characterized in that at least one of the pre-chambers is connected to a number of the gas distributing chambers by the connecting channels.
9. The gas distributor according to claim 1 , further characterized in that the gas distributing chambers ( 12 , 13 ) are disposed at different elevations within the second plane ( 9 ′).
10. The gas distributor according to claim 1 , further characterized in that a temperature of the gas distributor is controlled.
11. The gas distributor according to claim 1 , further characterized in that the gas distributor is produced from solid metal parts, which form a thermal mass for temperature homogenization.
12. The gas distributor according to claim 1 , further characterized in that the gas distributor comprises a number of disks placed on one another, into which the pre-chambers ( 10 , 10 ′, 11 ), the gas distributing chambers ( 12 , 13 ), the connecting channels ( 14 , 15 ) and the outlet openings ( 6 , 7 ) are machined.
13. The gas distributor according to claim 1 , further characterized in that portions of the at least one pre-chamber of one gas volume and portions of the at least one pre-chamber of another gas volume alternate with one another in a circumferential direction of the gas distributor.
14. The gas distributor according to claim 1 , further characterized in that the gas distributing chambers of one gas volume and the gas distributing chambers of another gas volume alternate with one another in a radial direction of the gas distributor.