Ex parte FUJII et al. - Page 2




               Appeal No. 1997-1696                                                                                                   
               Application 08/180,770                                                                                                 


               through 43 and 45, all of the claims pending in the  present application.                                              



                       Claims 1 through 19,  29, 35 and 44 have been canceled.                                                        

                       The invention relates to the method of testing input circuits, such as data-in buffer circuits or              

               address buffers, for a semiconductor device.  In particular, the method utilizes a test wherein a negative             

               potential is applied to the semiconductor device.  The method overcomes the prior art problem of                       

               generating minority carriers at a junction between the layer 22 and p-well region 26 as shown in figure 2              

               of the present application when a negative potential is applied V  .  On pages 8 and 9 of the                          
                                                                                   in                                                 
               specification, Appellants disclose that figure 4 shows a well region 16 is supplied with a potential which             

               is lower and has a greater magnitude than the potential of input signal V .  Appellants disclose that this             
                                                                                           in                                         
               arrangement prevents minority carriers generated when the potential V   is negative.  On pages 10                      
                                                                                         in                                           
               through 12 of the specification, Appellants disclose another embodiment shown in figure 6 in which a                   

               first power source potential V  is applied to the well regions 4 and 9 and a second power source                       
                                               ss                                                                                     
               potential V  is applied to a well region 14.  Appellants disclose that the first power source potential Vcc                                                                                      ss          
               is ground and the second power source potential V  is a potential greater than 0.  Appellants disclose                 
                                                                    cc                                                                
               that under this arrangement the minority carriers generated at the junction portion between layers 4 and               

               6 when V  is negative flow into well region 14.  This overcomes the problem of the reduction to Vin                                                                                     ref            
               due to the injection of minority carriers.                                                                             


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