Controlling the vaporization of organic material

Abstract

A method for controlling the deposition of vaporized organic material onto a substrate surface, includes providing a manifold having at least one aperture through which vaporized organic material passes for deposition onto the substrate surface; and providing a volume of organic material and maintaining the temperature of such organic material in a first condition so that its vapor pressure is below that needed to effectively form a layer on the substrate, and in a second condition heating a volume percentage of the initial volume of such organic material so that the vapor pressure of the heated organic material is sufficient to effectively form a layer.

1 . A method for controlling the deposition of vaporized organic material onto a substrate surface, comprising: 
 a) providing a manifold having at least one aperture through which vaporized organic material passes for deposition onto the substrate surface;    b) providing a volume of organic material and maintaining the temperature of such organic material in a first condition so that its vapor pressure is below that needed to effectively vaporize and form a layer on the substrate, and in a second condition heating a volume percentage of the initial volume of such organic material so that the vapor pressure of the heated organic material causes such material to vaporize and pass through the aperture in the manifold to form a layer on the substrate surface; and    c) providing a rotatable auger and metering by using such auger the organic material from the position where such organic material is in the first condition to the position where it is in the second condition to control the rate of vaporization.    
     
     
         2 . The method of  claim 1  wherein heating the volume percentage of the initial volume of organic material includes applying radiation onto an exposed surface of the organic material.  
     
     
         3 . The method of  claim 1  further providing a heating device that heats organic material to be in the second condition and stopping the vaporization by separating the heating device from the organic material.  
     
     
         4 . The method of  claim 1  further including heating the volume percentage of the initial volume by providing a permeable heating element in a temperature-controlled region and using such heated permeable heating element to vaporize organic material adjacent to such permeable heating element so that the vaporized organic material passes through the permeable heating element and into the manifold and out through the manifold aperture.  
     
     
         5 . (canceled)  
     
     
         6 . Apparatus for controlling the vaporization of organic materials in a vaporization source onto a substrate surface, which comprises: 
 a) first heating means for heating the organic material in a first temperature-controlled region until it is at a temperature below the vaporization temperature of the organic material;    b) second heating means for heating the organic material above the vaporization temperature in a second temperature-controlled region;    c) means for metering the organic material from the first temperature-controlled region to the second temperature-controlled region, whereby organic material vaporizes and forms on the substrate surface; and    d) means for controlling the temperature applied at the second temperature-controlled region.    
     
     
         7 . The apparatus of  claim 6  wherein the temperature controlling means includes means for separating the second heating device from the organic material, or means for decreasing the heat provided by the second heating device applied to the organic material, or both.  
     
     
         8 . The apparatus of  claim 6  wherein the second heating device includes a permeable heating element.  
     
     
         9 . The apparatus of  claim 6  wherein the second heating device includes means for applying radiation onto a surface of the organic material in the second temperature controlled region.  
     
     
         10 . The method of  claim 1  wherein during vaporization, less than 10% of the provided volume of organic material is heated to the second condition.