Evaporation source for evaporating an organic electroluminescent layer

Abstract

The present invention relates to an evaporation source for evaporating an organic electroluminescent layer. In particular, the present invention relates to the evaporation source preventing an aperture, through which a vaporized evaporation material is emitted, from being clogged by restricting heat transfer to outward. The evaporation source according to the present invention includes a cell retaining an evaporation material therein; a cell cap installed on the upper part of the cell and having a cell cap aperture for emitting a vaporized evaporation material; an external wall placed in the outside of the cell to support a heating means set up at the outside of the cell; a cover placed above the cell cap, fixed to the upper end of the external wall, and having a cover aperture corresponding to the cell cap aperture; and a shut-off plate placed between the cover and the cell cap and having a shut-off plate aperture corresponding to the cell cap aperture and the cover aperture in the center of the shut-off plate.

1 . An evaporation source heated by applied electric power, heating an evaporation material retained in the evaporation source, and emitting a vaporized evaporation material to form an evaporation material layer on a substrate, comprising: 
 a cell retaining the evaporation material therein;    a cell cap installed on the upper part of the cell, and having a cell cap aperture for emitting the vaporized evaporation material;    an external wall placed in the outside of the cell to support a heating means set up at the outside of the cell;    a cover placed above the cell cap, fixed to the upper end of the external wall, and having a cover aperture corresponding to the cell cap aperture; and    a shut-off plate placed between the cover and the cell cap, having a shut-off plate aperture corresponding to the cell cap aperture and the cover aperture in the center of the shut-off plate.    
     
     
         2 . The evaporation source of  claim 1 , wherein the outer circumferential surface of the shut-off plate is fixed to the inner circumferential surface of the cover.  
     
     
         3 . The evaporation source of  claim 1  or  claim 2 , wherein the shut-off plate is made of low conductivity material.  
     
     
         4 . The evaporation source of  claim 3 , wherein the shut-off plate is made of SUS material or tantalum.  
     
     
         5 . An evaporation source heated by applied electric power, heating an evaporation material retained in the evaporation source, and emitting a vaporized evaporation material to form an evaporation material layer on a substrate, comprising: 
 a cell retaining the evaporation material therein;    a cell cap installed on the upper part of the cell, and having a cell cap aperture for emitting the vaporized evaporation material;    an external wall placed in the outside of the cell to support a heating means set up at the outside of the cell;    a cover placed on the cell cap, fixed to the upper end of the external wall, and having a cover aperture corresponding to the cell cap aperture; and    an upper reflector and a lower reflector having an upper aperture and a lower aperture corresponding to the cover aperture in the center thereof, and placed above the cover to prevent heat from being emitted to the outside of the cover, wherein the upper reflector is placed above the lower reflector.    
     
     
         6 . The evaporation source of  claim 5 , wherein the upper reflector has a plurality of projections on the lower surface thereof, and the lower reflector has a plurality of recesses on the upper surface thereof to retain the projections of the upper reflector.  
     
     
         7 . The evaporation source of  claim 6 , wherein the recess of the lower reflector is of elliptical shape in which a long principal axis is circumferentially oriented and a short principal axis is radially oriented.  
     
     
         8 . The evaporation source of  claim 6 , wherein the projection of the upper reflector contacts the recess of the lower reflector at a point.  
     
     
         9 . The evaporation source of  claim 6 , wherein at least more than three pairs of the projections and recesses each are formed on the upper reflector and the lower reflector.  
     
     
         10 . An evaporation source heated by applied electric power, heating an evaporation material retained in the evaporation source, and emitting a vaporized evaporation material to form an evaporation material layer on a substrate, comprising: 
 a cell retaining the evaporation material therein;    a cell cap installed on the upper part of the cell, and having a cell cap aperture for emitting the vaporized evaporation material;    an external wall placed in the outside of the cell to support a heating means set up at the outside of the cell; and    a reflector comprising a body placed above the cell cap, a metal layer placed on the lower surface of the body, and a supporting member mounted on the body to contact the surface of the cell cap, wherein the body made of low conductivity material has a reflector aperture corresponding to the cell cap aperture in the center thereof, and the metal layer has a low emissivity value.    
     
     
         11 . The evaporation source of  claim 10 , wherein the body and the supporting member are made of ZrO 2 , Al 2 O 3 , TiO 2 , Mn, or Ti.  
     
     
         12 . The evaporation source of  claim 10 , wherein the supporting member and the body are formed integrally or separately.  
     
     
         13 . The evaporation source of  claim 10 , wherein the metal layer is made of Au, Ag, or Al.  
     
     
         14 . The evaporation source of  claim 13 , wherein the metal layer is formed on the lower surface of the body by the thermal spray method, ECM (Electro Chemical Metalizing) method, or the electro plating method, wherein the thermal spray method comprises the flame spray method, the plasma spray method, or HVOF (High Velocity Oxigen-Fuel).  
     
     
         15 . An evaporation source heated by applied electric power, heating an evaporation material retained in the evaporation source, and emitting a vaporized evaporation material to form an evaporation material layer on a substrate, comprising: 
 a cell retaining the evaporation material therein;    a cell cap installed on the upper part of the cell, and having a cell cap aperture for emitting the vaporized evaporation material;    an external wall placed in the outside of the cell to support a heating means set up at the outside of the cell; and    a cover contacting the upper surface of the cell cap, fixed to the upper end of the external wall, and having a cover aperture corresponding to the cell cap aperture.    
     
     
         16 . The evaporation source of  claim 15 , wherein the cover aperture and the cell cap aperture have the same size.  
     
     
         17 . The evaporation source of  claim 16 , wherein the thickness of the cover is decreased in the direction of the cover aperture.  
     
     
         18 . The evaporation source of  claim 15 , further including a shut-off layer formed on the upper surface of the cover, and having a shut-off layer aperture corresponding to the cover aperture.  
     
     
         19 . The evaporation source of  claim 18 , wherein the shut-off layer aperture has a larger size than the cover aperture.  
     
     
         20 . The evaporation source of  claim 18 , wherein the shut-off layer aperture and the cover aperture have the same size.  
     
     
         21 . The evaporation source of  claim 20 , wherein the thickness of the shut-off layer is decreased in the direction of the shut-off layer aperture.  
     
     
         22 . The evaporation source of  claim 20 , wherein the shut-off layer is formed by the electro plating method.  
     
     
         23 . The evaporation source of  claim 20 , wherein the shut-off layer is made of low conductivity material.  
     
     
         24 . The evaporation source of  claim 18 , wherein the shut-off layer is made of ceramic material or metal material, wherein the ceramic material comprises Al 2 O 3 , TiO 2 , SiC, or ZrO 2 , and the metal material comprises Mn or Ti.