Single reactor, multi-pressure chemical vapor deposition for semiconductor devices

Abstract

An apparatus and method for forming at least a portion of an electronic device include a High Vacuum-Chemical Vapor Deposition (UHV-CVD) system and a Low Pressure-Chemical Vapor Deposition (LPCVD) system using a common reactor. The invention overcomes the problem, of silicon containing wafers being dipped in HF acid prior to CVD processing, and the problem of surface passivation between processes in multiple CVD reactors.

1 - 12 . (canceled)  
   
   
       13 . A method for forming at least a portion of a semiconductor device, said method comprising steps of: 
 heating in a reaction chamber a substrate on which said semiconductor device is to be formed;    supplying a first treating gas to said reaction chamber from a first gas source;    maintaining said reaction chamber at a first vacuum pressure with a first pumping system during the supplying of said first treating gas to said reaction chamber;    stopping the supplying of said first treating gas and supplying a second treating gas to said reaction chamber from a second gas source;    maintaining said reaction chamber at the first vacuum pressure with the first pumping system during the supplying of said second treating gas to said reaction chamber,    supplying a third treatment gas and transitioning said reaction chamber between said first vacuum pressure and said second vacuum pressure using a third pumping system; and    supplying a fourth treatment gas at a second pressure and temperature.    
   
   
       14 . A method according to  claim 13 , wherein said first treating gas and said first vacuum pressure in said reaction chamber provide a low pressure chemical vapor deposition of a layer of silicon on said substrate.  
   
   
       15 . A method according to  claim 14 , wherein said first vacuum pressure is in the range of 100 to 500 mT.  
   
   
       16 . A method according to  claim 14 , wherein said fourth treating gas and said second vacuum pressure in said reaction chamber provide an ultra high vacuum deposition of a layer of Ge, Si or SiGe on said substrate.  
   
   
       17 . A method according to  claim 16 , wherein said second vacuum pressure is in the range of about 0.1 to 1.0 mT.  
   
   
       18 . A method according to  claim 13 , wherein said fourth treating gas and said second vacuum pressure in said reaction chamber provide an ultra high vacuum deposition of a layer of Ge, Si or SiGe on said substrate.  
   
   
       19 . A method according to  claim 13 , wherein said third pumping system is coupled to said reaction chamber and comprises a cryopump and a scroll pump arranged in series to remove contaminates from said reaction chamber after the supplying of said first treating gas.  
   
   
       20 . A method according to  claim 13 , wherein said first pumping system comprises a roots blower and a mechanical pump in series; wherein said second pumping system comprises a turbomolecular pump, a roots blower and a mechanical pump in series; and wherein said first pumping system and said second pumping system share the same roots blower and mechanical pump.