Apparatus for depositing an organic layer and method for controlling a heating unit thereof
An apparatus for depositing an organic layer and a method for controlling the heating unit thereof are provided. The apparatus includes a crucible positioned in a deposition chamber and containing materials for evaporation. The apparatus also includes a heating unit having first and second heat sources for heating the crucible. A housing isolates the heat emitted from the heating unit and an outer wall anchors the crucible. A nozzle sprays the materials evaporated from the crucible. The first and second heat sources are positioned on first and second sides of the crucible, respectively, and are independently controlled to minimize the time required to stabilize the deposition rate.
1. An apparatus for depositing an organic layer, the apparatus comprising:
a crucible positioned in a deposition chamber, the crucible being adapted to contain organic materials for evaporation,
a heating unit including first and second heat sources for applying heat to the crucible, wherein the first heat source is positioned near a first side of the crucible and the second heat source is positioned near a second side of the crucible, wherein a temperature of the second heat source is lower than the glass transition temperature of the organic materials in the crucible, the heating unit further comprising a first power source for supplying power to the first heat source, a second power source for supplying power to the second heat source, and a controller for independently controlling the first and second power sources, and for comparing a measured deposition rate to a reference deposition rate using a sensor unit, wherein the controller is configured to fix the power supplied to the second heat source and adjust the power supplied to the first heat source when the measured deposition rate reaches about 10% to about 70% of the reference deposition rate,
a first housing generally surrounding the heating unit and the crucible for isolating the heat emitted from the heating unit,
an outer housing generally surrounding the first housing, the outer housing configured to anchor the crucible, and
a nozzle for spraying the materials contained in the crucible onto a substrate.
2. The apparatus according to claim 1 , wherein the first and second heat sources each comprise a plate-type resistive heating source.
3. The apparatus according to claim 2 , wherein the plate-type resistive heating source is selected from the group consisting of carbon composites, SiC, and graphite.
4. The apparatus according to claim 2 , wherein the plate-type resistive heating source has a heating temperature ranging from about 150° C. to about 500° C.
5. The apparatus according to claim 1 , wherein each of the first and second heat sources comprises a heater and a reflector between the first housing and the heater, wherein the reflector prevents heat from transferring from the heaters to the outer wall.
6. The apparatus according to claim 1 , wherein each of the first and second heat sources comprises 2 reflectors or less.
7. An apparatus for depositing an organic layer, the apparatus comprising:
a crucible positioned in a deposition chamber, the crucible being adapted to contain organic materials for evaporation,
a heating unit including first and second heat sources for applying heat to the crucible, wherein the first heat source is positioned near a first side of the crucible and the second heat source is positioned near a second side of the crucible, wherein a temperature of the second heat source is lower than the glass transition temperature of the organic materials in the crucible, the heating unit further comprising a first power source for supplying power to the first heat source, a second power source for supplying power to the second heat source, and a controller for independently controlling the first and second power sources, and for comparing a measured deposition rate to a reference deposition rate using a sensor unit, wherein the controller is configured to fix the power supplied to the second heat source and adjust the power supplied to the first heat source when the measured deposition rate reaches about 10% to about 70% of the reference deposition rate,
a first housing generally surrounding the heating unit and crucible for isolating the heat emitted from the heating unit,
an outer housing generally surrounding the first housing, the outer housing configured to anchor the crucible, and
a nozzle for spraying the materials contained in the crucible onto a substrate.