Methods and apparatuses for roll-on coating

Abstract

Methods and apparatuses for a deposition system are provided to deposit a thin coating layer on flat substrates, such as semiconductors or panels. In an embodiment, liquid supplied rollers accepting liquid media provide liquid chemicals to the substrates for coating the substrates. The liquid delivery system can control the flow and the pressure of the liquid to achieve optimum process condition with minimum excess waste. In another embodiment, rollers with non-uniform distribution of liquid media provide a non-uniform thickness profile on the substrates, which can be used to compensate for the non-uniformity of subsequent processes.

What is claimed is: 
     
         1 . A method comprising:
 rotating a first roller to produce a first liquid coating layer on a substrate surface;   rotating a second roller to produce a second liquid coating layer on the substrate surface,   wherein the first liquid coating layer and the second liquid coating layer comprise different materials,   wherein the first liquid coating layer and the second liquid coating layer mix to form a liquid mixture.   
     
     
         2 . A method as in  claim 1  further comprising:
 drying the liquid mixture by at least one of drying rollers and IR lamp heaters. 
 
     
     
         3 . A method as in  claim 1  further comprising
 rotating a third roller to produce a third liquid coating layer on a substrate surface, 
 wherein the first liquid coating layer and the third liquid coating layer comprise a same material, 
 wherein the third roller is adjacent to the first roller or adjacent to the second roller, 
 wherein the third liquid coating layer is under or on the first and second liquid coating layers. 
 
     
     
         4 . A method as in  claim 1  further comprising
 rotating a third roller to produce a third liquid coating layer on a substrate surface, 
 wherein the second liquid coating layer and the third liquid coating layer comprise a same material, 
 wherein the third roller is adjacent to the first roller or adjacent to the second roller, 
 wherein the third liquid coating layer is under or on the first and second liquid coating layers. 
 
     
     
         5 . A method as in  claim 1  further comprising
 exposing the first and second coatings to a lamp heater, wherein the lamp heater is disposed adjacent to the first or second roller. 
 
     
     
         6 . A method as in  claim 1  further comprising
 exposing the first and second coatings to first and second lamp heaters, wherein the first lamp heater is disposed between the first and second rollers, and the second lamp heater is disposed outside of the first and second rollers. 
 
     
     
         7 . A method comprising:
 rotating a roller to produce a coating layer on a substrate surface;   wherein the coating layer has a non-uniform thickness profile in a direction along a length of the roller,   wherein the non-uniform thickness profile is configured to compensate for a non-uniform subsequent process so that after the non-uniform subsequent process, a layer having a uniform property is achieved from the combination of the non-uniform coating and the non-uniform subsequent process.   
     
     
         8 . A method as in  claim 7   wherein the roller is configured to accept a fluid to be transferred to a portion of the outer surface of the roller.   
     
     
         9 . A method as in  claim 7   wherein the roller is configured to accept a fluid at an end of the roller, wherein the fluid is transferred to a portion of the outer surface of the roller.   
     
     
         10 . A method as in  claim 7   wherein the non-uniform thickness profile has a thickness thicker at two edges of the coating layer in the direction along the length of the roller than that at the middle of the coating layer.   
     
     
         11 . A method as in  claim 7   wherein the non-uniform thickness profile has a thickness thinner at two edges of the coating layer in the direction along the length of the roller than that at the middle of the coating layer.   
     
     
         12 . A method as in  claim 7   wherein the subsequent process comprises a process of annealing the coating layer, wherein the anneal process comprises a non-uniform heating profile, wherein the non-uniform thickness profile is configured to provide a uniform doping profile after the annealing process.   
     
     
         13 . A method as in  claim 7   wherein the subsequent process comprises a heating process, wherein the heating process comprises a non-uniform heating profile, wherein the non-uniform thickness profile is configured to provide a uniform doping profile after the heating process.   
     
     
         14 . A method as in  claim 7  further comprising
 rotating a second roller to produce a second coating layer on the coating layer. 
 
     
     
         15 . A method as in  claim 7  further comprising
 exposing the coating layer to a lamp heater, wherein the lamp heater is disposed adjacent to the roller. 
 
     
     
         16 . A method comprising:
 forming a coating layer on a substrate surface;   wherein the coating layer has a non-uniform thickness profile,   wherein the non-uniform thickness profile is configured to compensate for a non-uniform subsequent process so that after the non-uniform subsequent process, a uniform coating layer is achieved from the combination of the non-uniform coating and the non-uniform subsequent process.   
     
     
         17 . A method as in  claim 16   wherein the non-uniform thickness profile has a thickness thicker at an edge of the coating layer than that at the middle of the coating layer.   
     
     
         18 . A method as in  claim 16   wherein the non-uniform thickness profile has a thickness thinner at an edge of the coating layer than that at the middle of the coating layer.   
     
     
         19 . A method as in  claim 16   wherein the subsequent process comprises a heating process, wherein the heating process comprises a non-uniform heating profile, wherein the non-uniform thickness profile is configured to provide a uniform doping profile after the heating process.   
     
     
         20 . A method as in  claim 16  further comprising
 exposing the coating layer to a lamp heater, wherein the lamp heater is disposed adjacent to the roller.