Apparatus and method for in-situ cleaning of borosilicate (BSG) and borophosphosilicate (BPSG) films from CVD chambers

Abstract

A method for cleaning borosilicate (BSG) and borophosphosilicate (BPSG) films from CDV chambers including controlling the pressure within the chamber, introducing Ar into the chamber, introducing NF 3 into the chamber, adjustably spacing a heater relative to the chamber, and adjusting the temperature within the chamber.

What is claimed is:  
     
         1 . A method for cleaning a CVD reaction chamber, comprising the steps of: 
 controlling the pressure within the chamber;    introducing Ar into the chamber;    introducing NF 3  into the chamber;    adjustably spacing a heater relative to the chamber; and    adjusting the temperature within the chamber.    
     
     
         2 . The method of  claim 1 , wherein the pressure is controlled between 2.5 Torr and 4.5 Torr.  
     
     
         3 . The method of  claim 1 , wherein the pressure is controlled at about 3 Torr.  
     
     
         4 . The method of  claim 1 , wherein the Ar is introduced at a rate of about 1,500 sccm to about 1,800 sccm.  
     
     
         5 . The method of  claim 1 , wherein the Ar is introduced at a rate of about 1,600 sccm to about 1,750 sccm.  
     
     
         6 . The method of  claim 1 , wherein the NF 3  is introduced at a rate of about 1,100 sccm to about 1,200 sccm.  
     
     
         7 . The method of  claim 1 , wherein the NF 3  is introduced at a rate of about 1,150 sccm.  
     
     
         8 . The method of  claim 1 , wherein spacing the heater relative to the chamber comprises spacing the heater from greater than 600 mils to about 1,500 mils relative to a showerhead.  
     
     
         9 . The method of  claim 1 , wherein adjusting the temperature within the chamber comprises adjusting the temperature to be substantially identical to the temperature used in the deposition process.  
     
     
         10 . The method of  claim 1 , including the step of cleaning a backside of a throttle valve comprising setting a pressure set point to throttle to 1600 steps, introducing Ar at a rate of about 1,600 sccm into the chamber and introducing NF 3  at a rate of 1,150 sccm into the chamber.  
     
     
         11 . The method of  claim 1 , including the step of optimizing the clean duration for a specific film comprising correlating a clean endpoint with a change in a slope of a foreline pressure versus time plot graph.  
     
     
         12 . The method of  claim 11 , wherein said specific film includes one of Borosilicate (BSG) film and Borophosphosilicate (BPSG) film.  
     
     
         13 . The method of  claim 1 , including the step of optimizing the clean duration for a specific film comprising correlating a clean endpoint with a stabilization of a species selected from the group consisting of HF, SiFx, BF 3 , and F x .  
     
     
         14 . The method of  claim 13 , wherein said specific film includes one of Borosilicate (BSG) film and Borophosphosilicate (BPSG) film.  
     
     
         15 . The method of  claim 1 , including the step of optimizing the clean duration for a specific film comprising correlating the time to clean a window within a CVD reaction chamber with a second peak in a foreline pressure versus time plot graph.  
     
     
         16 . The method of  claim 15 , wherein said specific film includes one of Borosilicate (BSG) film and Borophosphosilicate (BPSG) film.  
     
     
         17 . An apparatus for cleaning a CVD reaction chamber, the apparatus comprising: 
 servo device for controlling the pressure within the chamber using PID methodology;    first mass-flow device for introducing Ar into the chamber;    second mass-flow device for introducing NF 3  into the chamber;    heater spacing device for adjustably spacing a heater relative to the chamber; and    temperature control device for adjusting the temperature within the chamber.    
     
     
         18 . A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for cleaning a CVD reaction chamber, the method steps comprising: 
 controlling the pressure within the chamber;    introducing Ar into the chamber;    introducing NF 3  into the chamber;    adjustably spacing a heater relative to the chamber; and    adjusting the temperature within the chamber.