Apparatus for fabricating tungsten contacts with tungsten nitride barrier layers in semiconductor devices

Abstract

A method forming a tungsten contact can include forming a contact hole in an interlayer dielectric layer to expose a portion of an underlying silicon based substrate and to form a side wall of the contact hole. A tungsten silicide layer can be formed on at least on the exposed portion of the substrate. A tungsten nitride layer can be conformally formed on a surface of the interlayer dielectric layer, on the tungsten silicide layer and on the side wall. A contact tungsten layer can be formed on the tungsten nitride layer to fill the contact hole. Related apparatus and contacts are also disclosed.

1 . An apparatus for forming a tungsten contact, comprising: 
 a load lock chamber configured to contain a wafer having a contact hole formed therein;    a transfer chamber connected to the load lock chamber and having a robot arm included therein configured to transfer the wafer between different chambers connected to the transfer chamber;    a pre-cleaning chamber connected to the transfer chamber and configured to contain the wafer during cleaning;    a first process chamber connected to the transfer chamber and configured for use in forming a tungsten silicide layer on the wafer;    a second process chamber connected to the transfer chamber and configured for use in forming a tungsten nitride layer on the wafer; and    a third process chamber connected to the transfer chamber and configured for use in forming a contact tungsten layer on the wafer.    
   
   
       2 . An apparatus according to  claim 1  wherein the first process chamber comprises an atomic layer deposition (ALD) chamber.  
   
   
       3 . An apparatus according to  claim 1  wherein the first process chamber comprises: 
 a supply means to supply a tungsten fluoride (WF 6 ) gas; and    a supply means to supply a silane (SiH 4 ) gas.    
   
   
       4 . An apparatus according to  claim 3  wherein the first process chamber further comprises a supply means to supply borane (B 2 H 6 ) gas.  
   
   
       5 . An apparatus according to  claim 1  wherein the second process chamber comprises an atomic layer deposition chamber.  
   
   
       6 . An apparatus according to  claim 8  wherein the second process chamber comprises: 
 a supply means to supply a borane (B 2 H 6 ) gas;    a supply means to supply a tungsten fluoride (WF 6 ) gas; and    a supply means to supply an ammonia (NH 3 ) gas.    
   
   
       7 . An apparatus according to  claim 1  wherein the third process chamber comprises a chemical vapor deposition (CVD) chamber.  
   
   
       8 . An apparatus according to  claim 1  wherein the pre-cleaning chamber comprises a dry cleaning chamber configured for use of a fluoride gas and/or an inert gas.  
   
   
       9 . An apparatus for forming a tungsten contact, comprising: 
 a load lock chamber configured to contain a wafer having a contact hole formed therein;    a transfer chamber connected to the load lock chamber and having a robot arm included therein configured to transfer the wafer between different chambers connected to the transfer chamber;    a pre-cleaning chamber connected to the transfer chamber and configured to contain the wafer during cleaning;    a first process chamber connected to the transfer chamber and configured for use in forming a tungsten silicide layer on the wafer;    a second process chamber connected to the transfer chamber and configured for use in forming a tungsten nitride layer on the wafer;    a third process chamber connected to the transfer chamber and configured for use in forming a contact tungsten layer on the wafer; and    a fourth process chamber connected to the transfer chamber and configured for use in conformally forming a tungsten layer on the wafer.    
   
   
       10 . An apparatus according to  claim 9  wherein the fourth process chamber comprises an atomic layer deposition chamber.  
   
   
       11 . An apparatus according to  claim 10  wherein the fourth process chamber comprises: 
 a supply means to supply a borane (B 2 H 6 ) gas; and    a supply means to supply a tungsten fluoride (WF 6 ) gas.    
   
   
       12 . An apparatus for forming a tungsten contact, comprising: 
 a load lock chamber configured to contain a wafer having a contact hole formed therein;    a transfer chamber connected to the load lock chamber and having a robot arm included therein configured to transfer the wafer between different chambers connected to the transfer chamber;    a pre-cleaning chamber connected to the transfer chamber and configured to contain the wafer during cleaning;    a first process chamber connected to the transfer chamber and configured for use in forming a tungsten silicide layer on the wafer;    a second process chamber connected to the transfer chamber and configured for use in forming a tungsten nitride layer on the wafer;    a third process chamber connected to the transfer chamber and configured for use in forming a contact tungsten layer on the wafer; and    a fourth process chamber connected to the transfer chamber and configured for use in conformally forming an adhesive tungsten layer on the wafer, wherein the adhesive tungsten layer is configured to improve adhesion force between the tungsten silicide layer and the tungsten nitride layer.    
   
   
       13 . An apparatus according to  claim 12  wherein the fourth process chamber is configured to form the adhesive tungsten layer using atomic layer deposition.