Vertical CVD apparatus for forming silicon-germanium film

Abstract

A vertical CVD apparatus is arranged to process a plurality of target substrates all together to form a silicon germanium film. The apparatus includes a reaction container having a process field configured to accommodate the target substrates, and a common supply system configured to supply a mixture gas into the process field. The mixture gas includes a first process gas of a silane family and a second process gas of a germane family. The common supply system includes a plurality of supply ports disposed at different heights.

1 . A vertical CVD apparatus for processing a plurality of target substrates all together to form a silicon germanium film, the apparatus comprising: 
 a reaction container having a process field configured to accommodate the target substrates;    a holder configured to hold the target substrates stacked at intervals within the reaction container;    a heater configured to heat the process field;    an exhaust system configured to exhaust the reaction container;    a common supply system including a plurality of supply ports disposed at different heights and configured to supply a mixture gas into the process field, the mixture gas comprising a first process gas of a silane family and a second process gas of a germane family;    a first gas supply circuit configured to supply the first process gas into the common supply system; and    a second gas supply circuit configured to supply the second process gas into the common supply system.    
   
   
       2 . The apparatus according to  claim 1 , further comprising a dopant gas supply circuit configured to supply a dopant gas into the process field, the dopant gas being used for doping the silicon germanium film with a carrier impurity.  
   
   
       3 . The apparatus according to  claim 1 , wherein the common supply system comprises a plurality of injectors, which extend within the reaction container and respectively have uppermost supply ports at different heights.  
   
   
       4 . The apparatus according to  claim 1 , wherein the common supply system comprises a pipe, which vertically extends within the reaction container and has the plurality of supply ports formed thereon.  
   
   
       5 . The apparatus according to  claim 4 , wherein the plurality of supply ports have a larger hole size at a higher position.  
   
   
       6 . The apparatus according to  claim 1 , further comprising a control section configured to control an operation of the apparatus, wherein the control section executes 
 forming a silicon germanium film by CVD on the target substrates within the process field, while setting the process field at a first temperature and a first pressure, and supplying a mixture gas comprising the first and second process gases into the process field through the plurality of supply ports.    
   
   
       7 . The apparatus according to  claim 6 , wherein the control section sets the first temperature to be within a range of from 350 to 650° C., and sets the first pressure to be within a range of from 10 to 130 Pa.  
   
   
       8 . A vertical CVD method for processing a plurality of target substrates all together to form a silicon germanium film, the method comprising: 
 placing a holder in a process field within a reaction container, the holder holding the target substrates stacked at intervals; and    forming a silicon germanium film by CVD on the target substrates within the process field, while setting the process field at a first temperature and a first pressure, and supplying a mixture gas into the process field through a plurality of supply ports disposed at different heights, the mixture gas comprising a first process gas of a silane family and a second process gas of a germane family.    
   
   
       9 . The method according to  claim 8 , wherein the first temperature is set to be within a range of from 350 to 650° C., and the first pressure is set to be within a range of from 10 to 130 Pa.