VAPOR DEPOSITION APPARATUS AND METHOD FOR COATING A SUBSTRATE IN A VACUUM CHAMBER
A crucible for flash evaporation of a liquid material is described. The crucible includes one or more sidewalls and a reservoir portion below the one or more sidewalls, the reservoir portion of having a first cross-section of a first size and a second cross-section above the first cross-section of a second size, the second size being larger than the first size.
1 . A crucible for flash evaporation of a liquid material, comprising:
one or more sidewalls; and
a reservoir portion below the one or more sidewalls, the reservoir portion having a first cross-section of a first size and a second cross-section above the first cross-section of a second size, the second size being larger than the first size.
2 . The crucible for flash evaporation of a liquid material according to claim 1 , further comprising:
an opening for a conduit guiding the liquid material in the crucible.
3 . The crucible for flash evaporation of a liquid material according to claim 2 , wherein the opening is provided in the one or more sidewalls or at the bottom of the reservoir portion.
4 . The crucible for flash evaporation of a liquid material according to claim 1 , wherein the one or more sidewalls and the reservoir portion are integrally formed.
5 . The crucible for flash evaporation of a liquid material according to claim 1 , wherein the crucible comprises or consists of stainless steel, Mo, Ta or combinations thereof.
6 . The crucible for flash evaporation of a liquid material according to claim 1 , further comprising:
a vapor passage for the evaporated material, the vapor passage being provided at an upper end of the one or more sidewalls.
7 . The crucible for flash evaporation of a liquid material according to claim 1 , wherein the reservoir portion has a further cross-section being selected from the group consisting of:
a semi-circular cross-section, a cross-section corresponding to a portion of an oval, and a tapered cross-section.
8 . The crucible for flash evaporation of a liquid material according to claim 1 , wherein at least one of the first cross-section and the second cross-section is a circle, an oval, or a polygon.
9 . The crucible for flash evaporation of a liquid material according to claim 1 , wherein the first size of the first cross-section is a first perimeter of the first cross-section and the second size of the second cross-section is a second perimeter of the second cross-section.
10 . A vapor deposition apparatus, comprising:
a crucible according to claim 1 .
11 . The vapor deposition apparatus according to claim 10 , further comprising:
a flow meter with a measuring unit external to a conduit for guiding the liquid material.
12 . The vapor deposition apparatus according to claim 11 , wherein the flow meter is a Coriolis flow meter.
13 . The vapor deposition apparatus according to claim 10 , further comprising:
a flow valve having a regulating element external to the conduit for the liquid material.
14 . The vapor deposition apparatus according to claim 13 , further comprising:
a control valve configured to adjust a gas pressure at the flow valve.
15 . The vapor deposition apparatus according to claim 14 , further comprising:
a flow restriction element configured to reduce the gas pressure at the flow valve.
16 . The vapor deposition apparatus according to claim 14 , further comprising:
a controller configured to provide a closed loop control, the controller being connected to the flow meter and the control valve.
17 . A vapor deposition apparatus configured to evaporate one of the group consisting of an alkali metal and alkaline earth metals, comprising:
a flow meter with a measuring unit external to a conduit for the liquid material.
18 . The vapor deposition apparatus configured to evaporate one of the group consisting of an alkali metal and alkaline earth metals according to claim 17 , further comprising:
a flow valve having a regulating element external to the conduit for the liquid material.
19 . The vapor deposition apparatus according to claim 10 , further comprising:
a vapor distribution enclosure in fluid communication with the crucible, the vapor distribution enclosure having a plurality of nozzles.
20 . A method of coating a substrate in a vacuum chamber, comprising:
guiding a liquid material into a crucible according to claim 1 for flash evaporation;
flash evaporating the liquid material in the crucible; and
measuring a flow rate of the liquid material to control a deposition rate of the material on the substrate.