Method of decontamination of process chamber after in-situ chamber clean

Abstract

A method and apparatus for removing deposition products from internal surfaces of a processing chamber, and for preventing or slowing growth of such deposition products. A halogen containing gas is provided to the chamber to etch away deposition products. A halogen scavenging gas is provided to the chamber to remove any residual halogen. The halogen scavenging gas is generally activated by exposure to electromagnetic energy, either inside the processing chamber by thermal energy, or in a remote chamber by electric field, UV, or microwave. A deposition precursor may be added to the halogen scavenging gas to form a deposition resistant film on the internal surfaces of the chamber. Additionally, or alternately, a deposition resistant film may be formed by sputtering a deposition resistant metal onto internal components of the processing chamber in a PVD process.

1 . A method of cleaning group III nitride deposits formed on a gas distributor during a processing run in a deposition chamber, the method comprising:
 forming a sacrificial coating on the gas distributor prior to the processing run;   after the processing run, exposing the group III nitride deposits and the sacrificial coating to an activated halogen containing gas; and   etching the sacrificial coating and the group III nitride deposits, wherein the sacrificial coating is etched faster than the group III nitride deposits.   
     
     
         2 . The method of  claim 1 , wherein the sacrificial coating comprises aluminum, silicon, or both. 
     
     
         3 . The method of  claim 1 , wherein etching the group III nitride deposits comprises converting the group III nitride deposits to group III halide solids and removing the group III halide solids. 
     
     
         4 . The method of  claim 1 , wherein the halogen gas is activated by heating to a temperature above 600° C. 
     
     
         5 . The method of  claim 1 , wherein the sacrificial coating comprises nitrogen and at least one of silicon and aluminum. 
     
     
         6 . The method of  claim 1 , wherein providing a sacrificial coating on the gas distributor comprises reacting an organoaluminum compound, an organosilicon compound, or a mixture thereof with a nitrogen containing compound to deposit a layer comprising nitrogen and at least one of silicon and aluminum on the gas distributor. 
     
     
         7 . The method of  claim 6 , wherein the organoaluminum and organosilicon compounds are provided to the deposition chamber through a first pathway and the nitrogen containing compound is provided to the deposition chamber through a second pathway. 
     
     
         8 . The method of  claim 7 , wherein one of the first pathway and the second pathway bypasses the gas distributor. 
     
     
         9 . The method of  claim 6 , wherein the gas distributor comprises a first gas pathway and a second gas pathway, the organosilicon or organoaluminum compounds are flowed through the first gas pathway at a first volumetric flow rate, an inert gas is flowed through the second gas pathway at a second volumetric flow rate, and the first and second volumetric flow rates are substantially equal. 
     
     
         10 . The method of  claim 9 , wherein the nitrogen containing compound is flowed through a third gas pathway that bypasses the gas distributor. 
     
     
         11 . The method of  claim 3 , wherein converting the group III nitride deposits to group III halide solids comprises reacting the activated halogen containing gas with the group III nitride deposits and the sacrificial coating at a temperature above about 600° C. 
     
     
         12 . The method of  claim 3 , wherein removing the group III halide solids comprises heating the group III halide solids to a temperature above about 1,000° C. at a pressure below about 50 Torr. 
     
     
         13 . The method of  claim 3 , wherein the converting and removing are repeated. 
     
     
         14 . A method of removing group III nitride deposits from a gas distributor in a process chamber, comprising:
 exposing the gas distributor to a halogen containing gas;   reacting the halogen containing gas with the group III nitride deposits to form volatile species; and   exposing the gas distributor to an active nitrogen containing gas.   
     
     
         15 . The method of  claim 14 , wherein the halogen containing gas is a mixture of chlorine gas and a carrier gas. 
     
     
         16 . The method of  claim 14 , wherein the active nitrogen containing gas comprises ammonia, hydrazine, nitrogen gas, or any mixture thereof heated to at least about 500° C. 
     
     
         17 . The method of  claim 16 , wherein the active nitrogen containing gas comprises ammonia heated to at least about 1,000° C. 
     
     
         18 . The method of  claim 14 , further comprising exposing the gas distributor to a plasma formed from an inert gas and exposing the gas distributor to an activated scavenging gas. 
     
     
         19 . A method of operating a deposition chamber having a gas distributor with a surface exposed to the processing environment, the method comprising:
 forming a sacrificial coating on the surface of the gas distributor;   depositing a group III nitride material on a substrate in the deposition chamber and on the coated surface of the gas distributor by providing a group III metal precursor and a nitrogen containing precursor to the deposition chamber;   purging the group III metal precursor from the deposition chamber using the nitrogen containing precursor;   providing a halogen containing gas to the deposition chamber;   activating the halogen containing gas by heating the halogen containing gas to a temperature above about 600° C.;   reacting the active halogen containing gas with the sacrificial layer and with the group III nitride deposits on the sacrificial coating at a pressure between about 100 Torr and about 200 Torr to remove the sacrificial coating and convert the group III nitride deposits to group III halide deposits;   removing the group III halide deposits by increasing the temperature to at least about 1,000° C. and reducing the pressure to less than about 50 Torr; and   heat-soaking the gas distributor at a temperature above about 1,000° C. under an inert atmosphere.   
     
     
         20 . The method of  claim 19 , wherein reacting the active halogen containing gas with the sacrificial layer and with the group III nitride deposits and removing the group III halide deposits are repeated. 
     
     
         21 . The method of  claim 20 , wherein depositing a group III nitride material on a substrate is repeated. 
     
     
         22 . The method of  claim 21 , wherein purging the group III metal precursor from the deposition chamber comprises cycling the chamber pressure.