Process and device for upgrading current emission

Abstract

An art is provided to realize a current emitting device capable of emitting current of higher density under the same or lower onset emission voltage. The current emitting device is preferably an array of carbon nanotubes or a film including carbon nanotubes. The art is based on using O 2 , and/or O 3 , and/or CO 2 , and/or NO 2 , and/or SO 2 , and/or SO 3 to oxidize a current emitting device composed of material including carbon, until the current emitting device has at least part thereof changed in shape. The current emitting device thus processed works better with a display, or becomes capable of emitting current of higher density under the same or lower onset emission voltage. As far as experiments showed, the emitted current density achieved by the art can be eight times the amount emitted by an array of nanotubes having not been processed according to the art, and the onset emission voltage can be lowered by the art from 0.8 V/μm to 0.5 V/μm.

1 . A process applied to a current emitting device having an exposed portion and being composed of material including carbon, comprising: 
 oxidizing said current emitting device at an operating temperature until the shape of at least part of said exposed portion changes, said operating temperature being higher than ambient temperature.    
     
     
         2 . The process according to  claim 1  wherein said current emitting device is in the shape of a tube.  
     
     
         3 . The process according to  claim 1  wherein said current emitting device is in the shape of a ball.  
     
     
         4 . The process according to  claim 1  wherein said current emitting device is a carbon nanotube.  
     
     
         5 . The process according to  claim 1  wherein said operating temperature is at least 70° C.  
     
     
         6 . The process according to  claim 1  wherein at least part of said exposed portion is exposed to one type of gaseous material.  
     
     
         7 . The process according to  claim 6  wherein said gaseous material is at least one selected from among O 2 , O 3 , CO 2 , NO 2 , SO 2 , and SO 3 .  
     
     
         8 . The process according to  claim 1  wherein the shape of said exposed portion changes in such a way that at least part of said exposed portion becomes to be in the shape of a tip.  
     
     
         9 . The process according to  claim 1  wherein the shape of said exposed portion changes in such a way that at least part of said exposed portion is depressed.  
     
     
         10 . A process applied to a current emitting device composed of material including carbon, comprising: 
 oxidizing said current emitting device by a fluid including O 3  until said current emitting device has at least part thereof changed in shape.    
     
     
         11 . The process according to  claim 10  wherein said current emitting device is oxidized at a temperature which is at least negative 50° C.  
     
     
         12 . The process according to  claim 10  wherein said current emitting device has the shape thereof changed in such a way that at least part thereof becomes to be in the shape of a tip.  
     
     
         13 . The process according to  claim 10  wherein said current emitting device has the shape thereof changed in such a way that at least part thereof is depressed.  
     
     
         14 . A process applied to a current emitting device composed of material including carbon, comprising: 
 splitting some C═C double bonds of carbon in said current emitting device until the shape of at least part of said current emitting device changes in such a way that the current emission capability of said current emitting device increases.    
     
     
         15 . A current emitting device comprising an array of carbon nanotubes, wherein said nanotube comprises: 
 a first portion for connecting a carrier; and    a second portion with a surface including at least a depression and having an oxygenated group thereon.    
     
     
         16 . The current emitting device according to  claim 15  wherein said oxygenated group includes at least one of alcohol group (—>COH), ester group (—COO—), ether group (C—O—C linear structure), and epoxide group (COC).  
     
     
         17 . The current emitting device according to  claim 15  wherein said oxygenated group includes at least one of carboxylic acid group (—COOH), hydroxyl group (—OH), ketone group (>C═O), and aldehyde group (—CHO).  
     
     
         18 . A current emitting device comprising an array of carbon nanotubes, wherein said nanotube comprises: 
 a first portion for connecting a carrier; and    a second portion with a surface including at least a tip and having an oxygenated group thereon.    
     
     
         19 . The current emitting device according to  claim 18  wherein said oxygenated group includes at least one of alcohol group (—>COH), ester group (—COO—), ether group (C—O—C linear structure), and epoxide group (COC tricyclic ring).  
     
     
         20 . The current emitting device according to  claim 18  wherein said oxygenated group includes at least one of carboxylic acid group (—COOH), hydroxyl group (—OH), ketone group (>C═O), and aldehyde group (—CHO).