Apparatus and method for depositing a material on a substrate
View Patent ↗Apparatus and a method for depositing a material on a substrate utilizes a distributor including a permeable member through which a carrier gas and a material are passed to provide a vapor that is deposited on a conveyed substrate. A secondary gas can be provided to promote uniform distribution of the material on the substrate.
1. A method for depositing a material on a substrate, comprising:
heating a permeable member, wherein the permeable member comprises an elongated tubular shape with a first end located opposite to a second end;
passing a carrier gas and a material to be deposited into the heated permeable member to provide a deposition vapor which exits along a length of the heated permeable member;
conveying the substrate adjacent to the heated permeable member for depositing the vapor exiting the heated permeable member as a layer of the material on the substrate, wherein the deposition vapor can produce a deposited material layer having a first region and a second region, where the thickness of the first region is greater than the thickness of the second region;
passing a secondary gas, free of material to be deposited, into at least the first end of the heated permeable member containing the carrier gas and the material to be deposited via a gas supply line contained within the heated permeable member, wherein the gas supply line is separate from the material supply conduits and has a plurality of orifices internal to the heated permeable member for introducing the secondary gas into the heated permeable member at locations corresponding to areas of the heated permeable member at which the deposition vapor produces the first region and the second region; and
controlling a thickness uniformity of the deposited material by providing a substantially uniform vapor flow from the heated permeable member, wherein the plurality of orifices of the gas supply line are configured to supply a higher flow of the secondary gas to locations corresponding to areas of the heated permeable member which produces the first region than supplied to locations corresponding to areas of the heated permeable member which produce the second region to thereby decrease a thickness variation across the first region and second region.
2. The method of claim 1 , wherein heating the permeable member includes applying an electrical voltage across the opposite ends of the permeable member.
3. The method of claim 2 , further comprising guiding the vapor around the exterior of the permeable member with a shroud and passing the vapor outwardly through an opening in the shroud for the deposition on the substrate.
4. The method of claim 3 , wherein the opening in the shroud is a slit-shaped opening having opposite ends between which the opening has a varying gap size.
5. The method of claim 1 , wherein the secondary gas is passed into the heated permeable member via a plurality of gas supply lines.
6. The method of claim 1 , wherein the plurality of orifices include a plurality of holes.
7. The method of claim 1 , wherein the plurality of orifices include a plurality of nozzles.
8. The method of claim 1 , wherein the gas supply line is generally tubular and the plurality of orifices occur at regular intervals along the gas supply line.
9. The method of claim 1 , wherein the gas supply line is generally tubular and the plurality of orifices occur at irregular intervals along the gas supply line.
10. The method of claim 1 , further comprising introducing the material as a powder into the carrier gas.
11. The method of claim 1 , wherein the material is introduced by a rotary screw.
12. The method of claim 1 , wherein the material is introduced by a vibratory feeder.
13. The method of claim 1 , wherein the substrate is conveyed in a horizontally extending orientation thereby providing the substrate with a downwardly facing surface and an upwardly facing surface.
14. The method of claim 13 , wherein the vapor deposits on the upwardly facing surface of the conveyed substrate.
15. The method of claim 1 , wherein the substrate is conveyed by a gas hearth in a generally horizontally extending orientation thereby providing the substrate with an upwardly facing surface and a downwardly facing surface, and the vapor deposits on the downwardly facing surface of the conveyed substrate.
16. The method of claim 1 , wherein the material is a semiconductor.
17. The method of claim 1 , wherein the carrier gas and the secondary gas are the same gas.
18. The method of claim 1 , wherein the carrier gas and the secondary gas are different gasses.
19. The method of claim 1 , wherein the secondary gas is a reactive gas.
20. The method of claim 1 , wherein the plurality of orifices are spaced linearly along the gas supply line internal to the permeable member.
21. The method of claim 1 , wherein the gas supply line extends an entire length of the permeable member.
22. The method of claim 21 , further comprising controlling a distribution of the vapor deposited along a length of the permeable member by passing the secondary gas from one of the opposite ends of the permeable member.