Low-temperature selective epitaxial growth of silicon for device integration

Abstract

An epitaxy method includes providing an exposed crystalline region of a substrate material. Silicon is epitaxially deposited on the substrate material in a low temperature process wherein a deposition temperature is less than 500 degrees Celsius. A source gas is diluted with a dilution gas with a gas ratio of dilution gas to source gas of less than 1000.

What is claimed is: 
     
         1 . An epitaxy method, comprising:
 providing an exposed crystalline region of a III-V substrate material; and   epitaxially depositing silicon on the substrate material in a low temperature process wherein a deposition temperature is less than 500 degrees Celsius, by:   diluting a source gas with a dilution gas including at least one of H 2 , HCl, Cl 2  and Ar with a gas ratio of dilution gas to source gas of less than 1000.   
     
     
         2 . The method as recited in  claim 1 , wherein the epitaxially depositing silicon includes a radio frequency or direct current plasma enhanced chemical vapor deposition process. 
     
     
         3 . The method as recited in  claim 1 , wherein the source gas includes one of SiH 4 , dichlorosilane (DCS), SiF 4  or SiCl 4 . 
     
     
         4 . The method as recited in  claim 1 , wherein the deposition temperature is less than 250 degrees Celsius. 
     
     
         5 . The method as recited in  claim 1 , wherein the substrate material includes one of Si, Ge, and III-V materials. 
     
     
         6 . The method as recited in  claim 1 , wherein diluting includes diluting SiH 4  with H 2  with a gas ratio of over 5. 
     
     
         7 . The method as recited in  claim 1 , further comprising introducing a dopant with a gas ratio which provides a doped epitaxial silicon. 
     
     
         8 . The method as recited in  claim 7 , wherein the doped epitaxial silicon includes at least one of carbon, germanium, phosphorus, arsenic or boron. 
     
     
         9 . An epitaxy method, comprising:
 providing an exposed crystalline region of a germanium containing substrate material; and   epitaxially depositing silicon on the substrate material in a low temperature process wherein a deposition temperature is less than 500 degrees Celsius, by:   diluting a source gas with a dilution gas including at least one of H 2 , HCl, Cl 2  and Ar with a gas ratio of dilution gas to source gas of less than 1000.   
     
     
         10 . The method as recited in  claim 9 , wherein the epitaxially depositing silicon includes a radio frequency or direct current plasma enhanced chemical vapor deposition process. 
     
     
         11 . The method as recited in  claim 9 , wherein the source gas includes one of SiH 4 , dichlorosilane (DCS), SiF 4  or SiCl 4 . 
     
     
         12 . The method as recited in  claim 9 , wherein the deposition temperature is less than 250 degrees Celsius. 
     
     
         13 . The method as recited in  claim 9 , wherein the substrate material includes one of Si, Ge, and III-V materials. 
     
     
         14 . The method as recited in  claim 9 , wherein diluting includes diluting SiH 4  with H 2  with a gas ratio of over 5. 
     
     
         15 . The method as recited in  claim 9 , further comprising introducing a dopant with a gas ratio which provides a doped epitaxial silicon. 
     
     
         16 . The method as recited in  claim 15 , wherein the doped epitaxial silicon includes at least one of carbon, germanium, phosphorus, arsenic or boron. 
     
     
         17 . An epitaxy method, comprising:
 providing an exposed crystalline region of a type III-V substrate material;   epitaxially depositing crystalline silicon directly on the substrate material that is crystalline in a low temperature process wherein a deposition temperature is less than 500 degrees Celsius, the epitaxial depositing crystalline silicon including introducing a phosphorus dopant with a phosphine (PH 3 ) gas ratio to silicon containing gas of SiH 4  that ranges from 5 to 8 which provides doped epitaxial crystalline silicon, and   diluting the silicon containing gas of SiH 4 , with a gas ratio of the dilution gas of H 2  to the silicon containing gas of SiH 4  of 5 to 10, wherein said phosphorus dopant is present at a concentration in the crystalline silicon ranging from substantially 1×10 20  atoms/cm −3  to substantially 1×10 21  atoms/cm −3  to provide a sheet resistance ranging from substantially 1 KΩ/sq to 0.1 KΩ/sq, wherein a level of electrically active dopants is equal to said concentration of the phosphorus dopant in the crystalline silicon.   
     
     
         18 . The method as recited in  claim 17 , wherein the epitaxially depositing silicon includes a radio frequency or direct current plasma enhanced chemical vapor deposition process. 
     
     
         19 . The method as recited in  claim 17 , wherein the deposition temperature is less than 250 degrees Celsius. 
     
     
         20 . The method as recited in  claim 17 , wherein the doped epitaxial crystalline silicon includes at least one of carbon, germanium and combinations thereof.