Semiconductor configuration with an Ohmic contact-connection and method for contacting a semiconductor configuration

Abstract

A semiconductor configuration with an ohmic contact-connection includes a p-conducting semiconductor region made of silicon carbide. A p-type contact region serves for the contact-connection. The p-type contact region is composed of a material containing at least nickel and aluminum. A substantially uniform material composition is present in the entire p-type contact region. A method for contact-connecting p-conducting silicon carbide with a material containing at least nickel and aluminum is also provided. The two components nickel and aluminum are applied simultaneously on the p-conducting semiconductor region.

We claim:  
     
         1 . A semiconductor configuration with an ohmic contact-connection, comprising: 
 at least one p-conducting semiconductor region composed of silicon and carbon in a form of silicon carbide;    at least one p-type contact region adjoining said at least one p-conducting semiconductor region and composed of a material having nickel as a first material component and aluminum as a second material component, said at least one p-type contact region having a substantially uniform material composition throughout; and    a boundary region extending into said at least one p-conducting semiconductor region and into said at least one p-type contact region, said boundary region being composed substantially exclusively of said silicon and said carbon of said at least one p-conducting semiconductor region and of said nickel and said aluminum of said at least one p-type contact region.    
     
     
         2 . The semiconductor configuration according to    claim 1   , wherein said aluminum contained in said material has a proportion by volume of from 0.1% to 50%.  
     
     
         3 . The semiconductor configuration according to    claim 1   , wherein said aluminum contained in said material has a proportion by volume of from 20% to 50%.  
     
     
         4 . The semiconductor configuration according to    claim 1   , wherein said at least one p-conducting semiconductor region has a dopant concentration of between 10 17  cm −3  and 10 20  cm −3 .  
     
     
         5 . A method for contacting a semiconductor configuration, the method which comprises: 
 providing at least one p-conducting semiconductor region formed of silicon carbide; and    applying a material having nickel as a first material component and aluminum as a second material component on the at least one p-conducting semiconductor region for forming at least one substantially homogeneous p-type contact region on the at least one p-conducting semiconductor region, by simultaneously applying both, the first material component and the second material component such that a given mixture ratio of the first material component and the second material component is established at an interface between the at least one p-conducting semiconductor region and the at least one p-type contact region prior to a heat-treatment process.    
     
     
         6 . The method according to    claim 5   , which comprises providing the aluminum with a proportion by volume of from 0.1% to 50% in the material.  
     
     
         7 . The method according to    claim 5   , which comprises providing the aluminum with a proportion by volume of from 20% to 50% in the material.  
     
     
         8 . The method according to    claim 5   , which comprises providing a dopant concentration of between 10 17  cm −3  and 10 20  cm −3  in the at least one p-conducting semiconductor region.  
     
     
         9 . The method according to    claim 5   , which comprises applying the material by simultaneously vaporizing from two separate sources of the first and second material components.  
     
     
         10 . The method according to    claim 5   , which comprises applying the material by simultaneously sputtering from two separate sources of the first and second material components.  
     
     
         11 . The method according    claim 5   , which comprises: 
 preparing in advance a source material from the first and second material components; and    subsequently applying the material by sputtering the source material.    
     
     
         12 . The method according to    claim 5   , which comprises heat-treating a semiconductor configuration having the at least one p-conducting semiconductor region and the at least one p-type contact region by heating to a maximum temperature of at least 500° C.  
     
     
         13 . The method according to    claim 5   , which comprises heat-treating a semiconductor configuration having the at least one p-conducting semiconductor region and the at least one p-type contact region by heating to a maximum temperature of substantially 1000° C.  
     
     
         14 . The method according to    claim 12   , which comprises keeping the maximum temperature substantially constant for a duration of at most 2 hours.  
     
     
         15 . The method according to    claim 12   , which comprises keeping the maximum temperature substantially constant for a duration of at most 2 minutes.  
     
     
         16 . The method according to    claim 13   , which comprises keeping the maximum temperature substantially constant for a duration of at most 2 hours.  
     
     
         17 . The method according to    claim 13   , which comprises keeping the maximum temperature substantially constant for a duration of at most 2 minutes.