System and method for depositing a material on a substrate
View Patent ↗A method and apparatus for depositing a film on a substrate includes introducing a material and a carrier gas into a heated chamber. The material may be a semiconductor material, such as a cadmium chalcogenide. A resulting mixture of vapor and carrier gas containing no unvaporized material is provided. The mixture of vapor and carrier gas are remixed to achieve a uniform vapor/carrier gas composition, which is directed toward a surface of a substrate, such as a glass substrate, where the vapor is deposited as a uniform film.
1. A method for depositing a material on a substrate, comprising:
introducing a material including a powder and a carrier gas into a first chamber including an interior, wherein the first chamber is tubular and comprises:
a heating element positioned within the interior of the first chamber and heated by resistive heating to a temperature high enough that at least a portion of the powder vaporizes into a vapor; and a plurality of distribution holes,
wherein the first chamber is permeable to vapor but impermeable to powder, to ensure that powder is unable to pass through the first chamber;
heating the material such that at least a portion of the material vaporizes into a vapor and passes through the first chamber;
passing the vapor through at least one of the plurality of distribution holes in the first chamber into a second chamber, wherein the second chamber is tubular and is positioned outside the first chamber so that the second tubular chamber sheaths at least a portion of the first tubular chamber, and the second chamber is positioned to provide a material flow for the vapor that is sufficiently indirect to mix the vapor and the carrier gas into a substantially uniform vapor/carrier gas composition; and
directing the substantially uniform vapor/carrier gas composition through an outlet proximate to the second chamber and toward a surface of a substrate proximate to the second chamber and having a temperature lower than the vapor.
2. The method of claim 1 , wherein the second chamber comprises a plurality of distribution holes.
3. The method of claim 1 , wherein the material is a cadmium chalcogenide.
4. The method of claim 3 , wherein the material is cadmium telluride or cadmium sulfide.
5. The method of claim 1 , wherein heating includes maintaining the first chamber at a temperature of at least 500 degrees C.
6. The method of claim 5 , wherein the material is a cadmium chalcogenide and heating includes maintaining the first chamber at a temperature of at least 700 degrees C.
7. The method of claim 1 , wherein the first chamber comprises a distribution hole.
8. The method of claim 7 , wherein the first chamber comprises a plurality of distribution holes.