Reactive curing process for semiconductor substrates

Abstract

In some embodiments, a reactive curing process may be performed by exposing a semiconductor substrate in a process chamber to an ambient containing hydrogen peroxide, with the pressure in the process chamber at about 300 Torr or less. In some embodiments, the residence time of hydrogen peroxide molecules in the process chamber is about five minutes or less. The curing process temperature may be set at about 500° C. or less. The curing process may be applied to cure flowable dielectric materials and may provide highly uniform curing results, such as across a batch of semiconductor substrates cured in a batch process chamber.

1 - 31 . (canceled) 
     
     
         32 . A semiconductor processing system, comprising:
 a vertical furnace comprising a hot wall, batch process chamber configured to accommodate a plurality of semiconductor substrates in a wafer boat, wherein the semiconductor processing system is configured to:
 expose the semiconductor substrates in the process chamber to an ambient containing H 2 O 2 ; and 
 maintain a process chamber pressure at about 300 Torr or below while exposing the substrates to the ambient containing H 2 O 2 . 
   
     
     
         33 . The system of  claim 32 , wherein the semiconductor processing system is configured to maintain the process chamber pressure at about 150 Torr or below while exposing the substrates to the ambient containing H 2 O 2 . 
     
     
         34 . The system of  claim 32 , wherein the semiconductor processing system is configured to maintain a partial pressure of H 2 O 2  in the process chamber at about 1-100 Torr. 
     
     
         35 . The system of  claim 32 , wherein the semiconductor processing system is configured to maintain a process chamber temperature at about 50° to about 500° C. during exposing the semiconductor substrate. 
     
     
         36 . The system of  claim 32 , wherein the semiconductor processing system is configured to expose the semiconductor substrates in the process chamber to hydrogen while exposing the substrate to the ambient containing H 2 O 2 . 
     
     
         37 . The system of  claim 32 , further comprising:
 a liquid flow controller configured to meter the H 2 O 2  as a liquid upstream of the process chamber;   an evaporator configured to:
 receive the liquid from the liquid flow controller; and 
 evaporate the received liquid at an evaporator process temperature of 120° C. or below. 
   
     
     
         38 . The system of  claim 32 , wherein the ambient containing H 2 O 2  further comprises one or more additional oxidizing species different from H 2 O 2 , wherein the additional oxidizing species is chosen from the group consisting of ozone, oxygen, and H 2 O. 
     
     
         39 . The system of  claim 32 , wherein the semiconductor processing system is configured to reduce a pressure in the process chamber down to a curing pressure after loading the semiconductor substrates, wherein the process chamber is not evacuated below 50 Torr before commencing exposing the semiconductor substrates to the ambient containing H 2 O 2 . 
     
     
         40 . The system of  claim 32 , wherein the semiconductor processing system is configured to expose the semiconductor substrate to O 2  while loading the semiconductor substrate into the process chamber and/or during heat-up of the semiconductor substrate, and wherein the semiconductor processing system is configured to maintain a relatively low process chamber temperature while loading the semiconductor substrate, and to increase the process chamber temperature increases after starting exposing the semiconductor substrate. 
     
     
         41 . The system of  claim 32 , wherein the semiconductor processing system is configured to provide cyclically alternating oxidizing gases in the process chamber during exposing the semiconductor substrate,
 wherein providing cyclically alternating oxidizing gases comprises performing a plurality of cycles, each cycle comprising:
 sequentially exposing the semiconductor substrate to a first oxidizing gas comprising hydrogen peroxide and a second oxidizing gas comprising one or more gases selected from the group consisting of steam, ozone, and oxygen. 
   
     
     
         42 . A semiconductor processing system, comprising:
 a vertical furnace comprising a hot wall, batch process chamber configured to accommodate a plurality of semiconductor substrates in a wafer boat, wherein the semiconductor processing system is configured to:
 flow the H 2 O 2  species into the process chamber to expose the semiconductor substrates to an H 2 O 2  ambient, wherein the conditions of H 2 O 2  species flow rate, chamber pressure, and chamber temperature are such that an average residence time of the H 2 O 2  species in the process chamber is below about 5 minutes; and 
 exhaust gases of the H 2 O 2  ambient. 
   
     
     
         43 . The system of  claim 42 , wherein the semiconductor processing system is configured to establish conditions of H 2 O 2  species flow rate, chamber pressure, and chamber temperature such that the average residence time of the H 2 O 2  species in the reaction chamber is below about 2 minutes. 
     
     
         44 . The system of  claim 42 , wherein the semiconductor processing system is configured to deposit a dielectric material on the semiconductor substrate before flowing the H 2 O 2  species into the process chamber. 
     
     
         45 . The system of  claim 44 , wherein the semiconductor processing system is configured to reduce a pressure of the process chamber to a cure pressure during flowing the H 2 O 2  species, wherein the semiconductor processing system is configured to, before flowing the H 2 O 2  species, expose the semiconductor substrate only to pressures above the cure pressure. 
     
     
         46 . The system of  claim 42 , wherein the semiconductor processing system is configured to flow an oxidizing gas through the process chamber while loading the semiconductor substrates into the process chamber. 
     
     
         47 . The system of  claim 42 , wherein the process chamber is a batch process chamber configured to accommodate 20 or more substrates. 
     
     
         48 . The system of  claim 42 , wherein the semiconductor processing system is configured to anneal the semiconductor substrate after exhausting gases of the H 2 O 2  ambient. 
     
     
         49 . The system of  claim 48 , wherein the semiconductor processing system is configured to flow the H 2 O 2  species into the process chamber while maintaining the process chamber temperature at 300° C. or below, and wherein the semiconductor processing system is configured to anneal the semiconductor substrate at 400-800° C. 
     
     
         50 . The system of  claim 42 , wherein the semiconductor processing system is configured to, after annealing the substrate:
 flow H 2 O 2  species into the process chamber to expose the semiconductor substrate to an H 2 O 2  ambient; and   exhaust gases from the process chamber,   wherein the semiconductor processing system is configured to maintain an average residence time of the H 2 O 2  species in the process chamber at about 5 minutes or less.