Process and installation for doping an etched pattern of resistive elements

Abstract

A process for selectively doping predetermined resistive elements on an electronic chip is provided. The resistive elements are arranged in a pattern, and there are three phases in the process. The first phase electrically charges selected elements of the pattern. The second phase adds doping atoms to the charged elements as a function of their state of charge. The third phase anneals the electronic chip to cause penetration of the doping agents and to activate them.

1 - 14 . (canceled)  
   
   
       15 . An apparatus for selectively doping a pattern of electrically isolated resistive elements, the apparatus comprising: 
 a main lock; and    a plurality of chambers accessible through said main lock, said plurality of chambers comprising a first chamber for charging at least one selected element in the pattern, a second chamber for doping the at least one charged element as a function of charge, and a third chamber for annealing the pattern after doping.    
   
   
       16 . An apparatus according to  claim 15 , wherein the pattern of electrically isolated resistive elements are on a wafer.  
   
   
       17 . An apparatus according to  claim 16 , wherein said first chamber comprises an electron beam generator directed at the wafer.  
   
   
       18 . An apparatus according to  claim 16 , wherein said second chamber comprises a plasma generator for generating doping ions for the wafer.  
   
   
       19 . An apparatus according to  claim 16 , wherein said third chamber comprises a heater for annealing the wafer.  
   
   
       20 . An apparatus according to  claim 16 , further comprising first, second and third secondary locks associated with respective ones of said first, second and third chambers for receiving the wafer from said main lock.  
   
   
       21 . An apparatus according to  claim 15 , wherein said first chamber electrically charges all of the elements in the pattern, and discharges elements other than the one corresponding to the at least one selected element using a laser beam.  
   
   
       22 . An apparatus according to  claim 15 , wherein said second chamber causes ions to be absorbed on a surface of the charged elements.  
   
   
       23 . An apparatus according to  claim 22 , wherein the ions are produced using a plasma; and wherein the ions comprise at least one of boron, aluminum, indium, phosphorus, arsenic and antimony.  
   
   
       24 . An apparatus according to  claim 15 , wherein the at least one selected element comprises polysilicon.  
   
   
       25 . An apparatus for selectively doping a pattern of electrically isolated resistive elements on a wafer, the apparatus comprising: 
 a main lock; and    a plurality of chambers accessible through said main lock for receiving the wafer and comprising    a first chamber comprising an electron beam generator for charging at least one selected element in the pattern,    a second chamber comprising a plasma generator for generating doping ions for doping the at least one charged element as a function of charge, and    a third chamber comprising a heater for annealing the wafer after doping.    
   
   
       26 . An apparatus according to  claim 25 , further comprising first, second and third secondary locks associated with respective ones of said first, second and third chambers for receiving the wafer from said main lock.  
   
   
       27 . An apparatus according to  claim 25 , wherein said first chamber electrically charges all of the elements in the pattern, and discharges elements other than the one corresponding to the at least one selected element using a laser beam.  
   
   
       28 . An apparatus according to  claim 25 , wherein said second chamber causes ions to be absorbed on a surface of the charged elements.  
   
   
       29 . An apparatus according to  claim 28 , wherein the ions are produced using a plasma; and wherein the ions comprise at least one of boron, aluminum, indium, phosphorus, arsenic and antimony.  
   
   
       30 . An apparatus according to  claim 25 , wherein the at least one selected element comprises polysilicon.  
   
   
       31 . An apparatus for selectively doping a pattern of electrically isolated resistive elements, the apparatus comprising: 
 a main lock;    first, second and third secondary locks in selective communication with said main lock;    a first chamber associated with said first secondary lock for charging at least one selected element in the pattern;    a second chamber associated with said second secondary lock for doping the at least one charged element as a function of charge; and    a third chamber associated with said third secondary lock for annealing the pattern after doping.    
   
   
       32 . An apparatus according to  claim 31 , wherein the pattern of electrically isolated resistive elements are on a wafer.  
   
   
       33 . An apparatus according to  claim 31 , wherein said first chamber comprises an electron beam generator; wherein said second chamber comprises a plasma generator; and wherein said third chamber comprises a heater.  
   
   
       34 . An apparatus according to  claim 31 , wherein the at least one selected element comprises polysilicon.