Patent ID: 7815737

Claim:
A deposition source for forming deposition evaporation organic electroluminescent layers onto a substrate, by applying a vaporized deposition material generated therein onto the substrate, and by transferring heat to a vapor deposition material received therein onto the substrate, and by transferring heat to a vapor deposition material received therein, said deposition source comprising: a top plate that supplies heat to said deposition material and which has a vapor efflux aperture thereon; a baffle member fixed to the top plate by supporting members under the top plate; a sensing device disposed on said baffle member, sensing a height of said deposition material and generating sensing signals corresponding to the height of said deposition material wherein a backing surface of said sensing device faces said baffle member and a front surface of said sensing device faces the liquid surface of said vapor deposition material inside the container; a bottom plate; a side wall disposed between the top plate and the bottom plate; a plurality of heating coils disposed on an outer surface of the side wall from a first position corresponding to said sensing device in said deposition source to a second position corresponding to an inner bottom surface of the bottom plate, wherein the plurality of heating coils are electrically separated each other; a controller that selectively applies electric power to only a heating coil disposed on a position corresponding to the height of said deposition material according to the sensed signals.