Ex parte SHANFIELD et al. - Page 2

          Appeal No. 95-0926                                                          
          Application 08/026,222                                                      

                    This is a decision on appeal from the final rejection             
          of claims 9, 10 and 12 through 18, all of the claims pending in             
          the application.                                                            
                    The invention is directed to a semiconductor device.              
          More particularly, a negative surface potential is provided on an           
          exposed surface of the semiconductor between the gate electrode             
          and the source and/or drain.  The surface is then covered with a            
          passivating layer.  It is disclosed that by incorporating an                
          electro-negative species into the semiconductor surface, the                
          negative charge in the surface can be maintained after                      
          passivation, thus minimizing reductions in reverse breakdown                
                    Representative independent claim 9 is reproduced as               
                    9.   A field effect transistor comprising:                        
                    a substrate supporting an active layer comprising a               
          Group III-V material having a dopant concentration with a source            
          electrode and a drain electrode disposed thereover and with a               
          gate electrode disposed between said source and drain electrodes            
          in Schottky barrier contact to said active layer;                           
                    a surface layer portion of said active layer having               
          anions to provide a negatively charged surface potential disposed           
          between said drain and gate electrodes comprised of said Group              
          III-V material and oxygen having a thickness in the range of 25D            
          to 35D ; and                                                                
                    a layer of passivation material disposed at least on              
          said surface layer portion of said active layer.                            


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