Organic semicounductor device, process for producing the same, and organic semiconductor apparatus

Abstract

The present invention provides an organic semiconductor device, which can be produced uniformly on a large substrate, having a high mobility and capable of greatly modulating the drain current by varying the voltage applied to a gate electrode. The present invention provides an organic semiconductor device having at least a substrate, an organic semiconductor, a gate insulating film and conductors, and having electrodes for applying bias, wherein a polymer layer, which is different from the gate insulating film, is provided in contact with the organic semiconductor, and the polymer layer is formed of a copolymer of methyl methacrylate and divinylbenzene, or the like; a process for producing the organic semiconductor device; and an organic semiconductor apparatus using the organic semiconductor device.

1 . An organic semiconductor device comprising a substrate, an organic semiconductor, a gate insulating film and conductors, wherein a polymer layer, which is different from the gate insulating film, is provided in contact with the organic semiconductor, and the polymer layer contains a copolymer of methyl methacrylate and divinylbenzene.  
     
     
         2 . The organic semiconductor device according to  claim 1 , wherein the copolymer of methyl methacrylate (A) and divinylbenzene (B) has a monomer unit ratio of A:B=1:0.001 to 0.04.  
     
     
         3 . The organic semiconductor device according to  claim 1 , wherein the polymer layer has a thickness of 5 nm or more and 30 nm or less.  
     
     
         4 . The organic semiconductor device according to  claim 1 , wherein the polymer layer is provided between the organic semiconductor and the gate insulating film, and the gate insulating film has a surface with a surface roughness Ra of 5 nm or less, the surface being in contact with the polymer layer.  
     
     
         5 . An organic semiconductor device comprising a substrate, a organic semiconductor, a gate insulating film and conductors, wherein a polymer layer, which is different from the gate insulating film, is provided in contact with the organic semiconductor, and the polymer layer contains a polymer represented by the following formula (1) or (2):  
       
         
           
           
               
               
           
         
       
       wherein R 11  represents a hydrogen atom or an alkyl group, R 12  represents a naphthyl group which may be substituted, a carbazoyl group which may be substituted, or a biphenyl group which may be substituted, and n denotes polymerization degree; or  
       
         
           
           
               
               
           
         
       
       wherein R 21  represents a hydrogen atom or an alkyl group, the aromatic ring may be substituted, and n denotes polymerization degree.  
     
     
         6 . The organic semiconductor device according to  claim 5 , wherein the polymer layer contains a polymer represented by the following formula (3):  
       
         
           
           
               
               
           
         
       
       wherein R 31  represents a hydrogen atom or an alkyl group, R 32  represents a naphthyl or carbazoyl group, and n denotes polymerization degree.  
     
     
         7 . The organic semiconductor device according to  claim 5 , wherein the polymer layer has a thickness of 10 nm or more and 100 nm or less.  
     
     
         8 . The organic semiconductor device according to  claim 1 , wherein a gate electrode, the gate insulating film, the polymer layer, the organic semiconductor and source/drain electrodes are provided on the substrate in this order.  
     
     
         9 . The organic semiconductor device according to  claim 1 , wherein a gate electrode, the gate insulating film, the polymer layer, source/drain electrodes and the organic semiconductor are provided on the substrate in this order.  
     
     
         10 . The organic semiconductor device according to  claim 1 , wherein a gate electrode, the gate insulating film, source/drain electrodes, the polymer layer and the organic semiconductor are provided on the substrate in this order.  
     
     
         11 . The organic semiconductor device according to  claim 1 , wherein a gate electrode, the gate insulating film, one of source/drain electrodes, the organic semiconductor and the other of the source/drain electrodes are provided on the substrate in this order, and wherein the polymer layer is provided in contact with the organic semiconductor.  
     
     
         12 . The organic semiconductor device according to  claim 1 , wherein source/drain electrodes, the polymer layer, the organic semiconductor, the gate insulating film and a gate electrode are provided on the substrate in this order.  
     
     
         13 . The organic semiconductor device according to  claim 1 , wherein the polymer layer, source/drain electrodes, the organic semiconductor, the gate insulating film and a gate electrode are provided on the substrate in this order.  
     
     
         14 . The organic semiconductor device according to  claim 1 , wherein the polymer layer, the organic semiconductor, source/drain electrodes, the gate insulating film and a gate electrode are provided on the substrate in this order.  
     
     
         15 . The organic semiconductor device according to  claim 1 , wherein one of source/drain electrodes, the organic semiconductor, the other of the source/drain electrodes, the gate insulating film and a gate electrode are provided on the substrate in this order, and wherein the polymer layer is provided in contact with the organic semiconductor.  
     
     
         16 . The organic semiconductor device according to  claim 1 , wherein the polymer layer is formed by any one of spin coating, spray coating and dip coating.  
     
     
         17 . The organic semiconductor device according to  claim 1 , wherein the device is a field effect transistor.  
     
     
         18 . An organic semiconductor apparatus using the organic semiconductor device according to  claim 1 .  
     
     
         19 . A process for producing an organic semiconductor device, comprising the steps of: 
 forming an insulating film on a substrate having a surface, at least a part of the surface being conductive,    forming a polymer layer composed of a copolymer of methyl methacrylate and divinylbenzene on the insulating film, and    forming an organic semiconductor layer on the polymer layer.    
     
     
         20 . The process for producing the organic semiconductor device according to  claim 19 , further comprising a step of forming at least one pair of electrodes apart from each other on a part of the polymer layer.  
     
     
         21 . The process for producing the organic semiconductor device according to  claim 19 , further comprising a step of forming at least one pair of electrodes apart from each other on a part of the organic semiconductor layer.  
     
     
         22 . A process for producing the organic semiconductor device, comprising the steps of: 
 forming a polymer layer composed of a copolymer of methyl methacrylate and divinylbenzene,    forming an organic semiconductor layer on the polymer layer, and    forming an insulating film on the organic semiconductor layer.    
     
     
         23 . A process for producing the organic semiconductor device, comprising the steps of: 
 forming an insulating film on a substrate having a surface, at least a part of the surface being conductive,    forming, on the insulating film, a polymer layer composed of a polymer represented by the following formula (1) or (2):                          wherein R 11  represents a hydrogen atom or an alkyl group, R 12  represents a naphthyl group which may be substituted, a carbazoyl group which may be substituted, or a biphenyl group which may be substituted, and n denotes polymerization degree; or                          wherein R 21  represents a hydrogen atom or an alkyl group, the aromatic ring may be substituted, and n denotes polymerization degree, and    forming an organic semiconductor layer on the polymer layer.    
     
     
         24 . The process for producing the organic semiconductor device according to  claim 23 , further comprising a step of forming at least one pair of electrodes apart from each other on a part of the polymer layer.  
     
     
         25 . The process for producing the organic semiconductor device according to  claim 23 , further comprising a step of forming at least one pair of electrodes apart from each other on a part of the organic semiconductor layer.  
     
     
         26 . A process for producing the organic semiconductor device, comprising the steps of: 
 forming, on a substrate, a polymer layer composed of a polymer represented by the following formula (1) or (2):                          wherein R 11  represents a hydrogen atom or an alkyl group, R 12  represents a naphthyl group which may be substituted, a carbazoyl group which may be substituted, or a biphenyl group which may be substituted, and n denotes polymerization degree; or                          wherein R 21  represents a hydrogen atom or an alkyl group, the aromatic ring may be substituted, and n denotes polymerization degree,    forming an organic semiconductor layer on the polymer layer, and    forming an insulating film on the organic semiconductor layer.    
     
     
         27 . The process for producing the organic semiconductor device according to  claim 19 , wherein the polymer layer is formed by any one of spin coating, spray coating and dip coating.