Apparatus and method for selective oxidation at lower temperature using remote plasma source

Abstract

Devices and methods for selectively oxidizing silicon are described herein. An apparatus for selective oxidation of exposed silicon surfaces includes a thermal processing chamber with a plurality of walls, first inlet connection and a second inlet connection, wherein the walls define a processing region within the processing chamber, a substrate support within the processing chamber, a hydrogen source connected with the first inlet connection, a heat source connected with the hydrogen source, and a remote plasma source connected with the second inlet connection and an oxygen source. A method for selective oxidation of non-metal surfaces, can include positioning a substrate in a processing chamber at a temperature less than 800° C., flowing hydrogen into the processing chamber, generating a remote plasma comprising oxygen, mixing the remote plasma with the hydrogen gas in the processing chamber to create an activated processing gas, and exposing the substrate to the activated gas.

1 . An apparatus for selective oxidation of exposed silicon surfaces, comprising:
 a thermal processing chamber with a plurality of walls having a first inlet connection and a second inlet connection, wherein the plurality of walls define a processing region within the processing chamber;   a substrate support within the processing chamber;   a hydrogen source in fluid connection with the first inlet connection of the processing chamber;   a heat source in connection with the hydrogen source;   a remote plasma source in fluid connection with the second inlet connection of the processing chamber; and   an oxygen source in fluid connection with the remote plasma source.   
     
     
         2 . The apparatus of  claim 1 , wherein the heat source connects the hydrogen source to the first inlet connection of the processing chamber. 
     
     
         3 . The apparatus of  claim 1 , wherein the heat source is a resistive heat source. 
     
     
         4 . The apparatus of  claim 1 , further comprising:
 a hot wire apparatus formed in fluid communication between the hydrogen source and the processing chamber, such that the hydrogen gas is activated by the hot wire apparatus prior to entering the processing chamber.   
     
     
         5 . The apparatus of  claim 1 , wherein the fluid connection with the hydrogen source comprises tubing which comprises an inert material. 
     
     
         6 . A method for selective oxidation of non-metal surfaces, comprising:
 positioning a substrate in a processing chamber, wherein the processing chamber is maintained at a temperature less than 800° C.;   flowing hydrogen into the processing chamber;   generating a remote plasma comprising oxygen;   flowing the remote plasma into the processing chamber, wherein the remote plasma mixes with the hydrogen gas to create an activated processing gas; and   exposing the substrate to the activated gas.   
     
     
         7 . The method of  claim 6 , wherein hydrogen comprises at least 70 atomic percent as compared to oxygen. 
     
     
         8 . The method of  claim 7 , wherein hydrogen comprises at most 95 atomic percent of the activated processing gas. 
     
     
         9 . The method of  claim 6 , further comprising soaking the substrate in hydrogen prior to generating a remote plasma comprising oxygen. 
     
     
         10 . The method of  claim 9 , wherein the soak process is maintained at a temperature between 600° C. and 800° C. for at least 45 seconds. 
     
     
         11 . The method of  claim 9 , wherein the flow rates of hydrogen gas are from about 3.33 sccm/cm 2  to about 16.67 sccm/cm 2 . 
     
     
         12 . The method of  claim 9 , wherein the flow rates of hydrogen gas are from about 3.33 sccm/cm 2  to about 33.33 sccm/cm 2 . 
     
     
         13 . A method for selective oxidation of non-metal surfaces, comprising:
 positioning a substrate in a processing chamber, wherein the processing chamber is maintained at a temperature less than 800° C.;   flowing hydrogen in proximity to a hot wire apparatus to generate activated hydrogen;   flowing the activated hydrogen into the processing chamber;   generating a remote plasma comprising oxygen;   mixing the remote plasma with the hydrogen gas in the processing chamber to create an activated processing gas;   exposing the substrate to the activated gas to oxidize a desired amount of silicon, wherein the activated gas oxidizes silicon surfaces and reduces metal surfaces; and   cooling the substrate.   
     
     
         14 . The method of  claim 13 , wherein hydrogen comprises at least 70 atomic percent as compared to oxygen. 
     
     
         15 . The method of  claim 14 , wherein hydrogen comprises at most 95 atomic percent of the activated processing gas. 
     
     
         16 . The method of  claim 13 , further comprising soaking the substrate in hydrogen prior to generating a remote plasma comprising oxygen. 
     
     
         17 . The method of  claim 16 , wherein the soak process is maintained at a temperature between 600° C. and 800° C. for at least 45 seconds. 
     
     
         18 . The method of  claim 13 , wherein the flow rates of hydrogen gas are from about 3.33 sccm/cm 2  to about 16.67 sccm/cm 2 . 
     
     
         19 . The method of  claim 13 , wherein the flow rates of hydrogen gas are from about 3.33 sccm/cm 2  to about 33.33 sccm/cm 2 .