Oxidation apparatus and method for semiconductor process

Abstract

An oxidation apparatus for a semiconductor process includes a process container having a process field configured to accommodate target substrates at intervals vertically, a heater configured to heat the process field; an exhaust system configured to exhaust gas from inside the process field; an oxidizing gas supply circuit configured to supply an oxidizing gas to the process field; and a deoxidizing gas supply circuit configured to supply a deoxidizing gas to the process field. The oxidizing gas supply circuit includes an oxidizing gas nozzle extending over a vertical length corresponding to the process field, and having gas spouting holes arrayed over the vertical length corresponding to the process field. The deoxidizing gas supply circuit includes deoxidizing gas nozzles having different heights respectively corresponding to zones of the process field arrayed vertically, and each having a gas spouting hole formed at height of a corresponding zone.

1 . An oxidation apparatus for a semiconductor process, the apparatus comprising:
 a process container having a process field configured to accommodate a plurality of target substrates at intervals in a vertical direction,   a heater configured to heat the process field;   an exhaust system configured to exhaust gas from inside the process field;   an oxidizing gas supply circuit configured to supply an oxidizing gas to the process field; and   a deoxidizing gas supply circuit configured to supply a deoxidizing gas to the process field,   wherein the oxidizing gas supply circuit comprises an oxidizing gas nozzle extending over a vertical length corresponding to the process field, and having a plurality of gas spouting holes arrayed over the vertical length corresponding to the process field, and   the deoxidizing gas supply circuit comprises a plurality of deoxidizing gas nozzles having different heights respectively corresponding to a plurality of zones of the process field arrayed vertically, and each having a gas spouting hole formed at height of a corresponding zone.   
     
     
         2 . The apparatus according to  claim 1 , wherein the gas spouting holes of the oxidizing gas nozzle are arrayed essentially at regular intervals. 
     
     
         3 . The apparatus according to  claim 1 , wherein the gas spouting hole of each of the deoxidizing gas nozzles comprises a set of gas spouting holes arrayed within a corresponding zone. 
     
     
         4 . The apparatus according to  claim 1 , wherein the deoxidizing gas nozzles are configured to respectively control flow rates of the deoxidizing gas. 
     
     
         5 . The apparatus according to  claim 1 , wherein the oxidizing gas nozzle comprises a first portion extending from a first side to a second side in a vertical direction and a second portion extending from the second side to the first side in a vertical direction, and the first and second portion are connected through a bent portion. 
     
     
         6 . The apparatus according to  claim 5 , wherein the first portion is connected to a supply source of the oxidizing gas on the first side, and the second portion is closed on the first side. 
     
     
         7 . The apparatus according to  claim 6 , wherein the first portion has a plurality of first gas spouting holes formed at predetermined intervals, and the second portion has a plurality of second gas spouting holes respectively formed at centers between the first gas spouting holes. 
     
     
         8 . The apparatus according to  claim 7 , wherein the first and second gas spouting holes are directed to opposite sides. 
     
     
         9 . The apparatus according to  claim 7 , wherein the first gas spouting holes have the same opening surface area each other, and the second gas spouting holes have the same opening surface area each other. 
     
     
         10 . The apparatus according to  claim 1 , wherein each of the gas spouting holes has a gas spouting direction set in a tangential direction to a contour of the target substrate or in a direction outside the tangential direction. 
     
     
         11 . The apparatus according to  claim 10 , wherein each of the gas spouting holes has a gas spouting direction set to form an angle of 90° or more relative to a line connecting a center of a corresponding gas nozzle and a center of a corresponding target substrate. 
     
     
         12 . The apparatus according to  claim 1 , wherein the oxidizing gas comprises one or more gases selected from the group consisting of O 2 , N 2 O, NO, NO 2 , and O 3 , and the deoxidizing gas comprises one or more gases selected from the group consisting of H 2 , NH 3 , CH 4 , HCl, and deuterium. 
     
     
         13 . An oxidation method for a semiconductor process, the method comprising:
 placing a plurality of target substrates at intervals in a vertical direction within a process field of a process container;   respectively supplying an oxidizing gas and a deoxidizing gas to the process field, while heating the process field;   causing the oxidizing gas and the deoxidizing gas to react with each other, thereby generating oxygen radicals and hydroxyl group radicals within the process field; and   performing an oxidation process on a surface of the target substrates by use of the oxygen radicals and the hydroxyl group radicals,   wherein the oxidizing gas is supplied from an oxidizing gas nozzle extending over a vertical length corresponding to the process field, and having a plurality of gas spouting holes arrayed over the vertical length corresponding to the process field, and   the deoxidizing gas is supplied from a plurality of deoxidizing gas nozzles having different heights respectively corresponding to a plurality of zones of the process field arrayed vertically, and each having a gas spouting hole formed at height of a corresponding zone.   
     
     
         14 . The method according to  claim 13 , wherein each of the gas spouting holes has a gas spouting direction set in a tangential direction to a contour of the target substrate or in a direction outside the tangential direction. 
     
     
         15 . The method according to  claim 14 , wherein each of the gas spouting holes has a gas spouting direction set to form an angle of 90° or more relative to a line connecting a center of a corresponding gas nozzle and a center of a corresponding target substrate. 
     
     
         16 . The method according to  claim 13 , wherein the target substrates are held on a support member within the process field to fill the most upstream side of the support member, where the number of target substrates is smaller than that in a full load state of the support member. 
     
     
         17 . The method according to  claim 13 , wherein the oxidizing gas comprises one or more gases selected from the group consisting of O 2 , N 2 O, NO, NO 2 , and O 3 , and the deoxidizing gas comprises one or more gases selected from the group consisting of H 2 , NH 3 , CH 4 , HCl, and deuterium. 
     
     
         18 . The method according to  claim 13 , wherein the method further comprises:
 obtaining reference conditions of the oxidation process for reference substrates each having a reference surface area, while satisfying a predetermined level of inter-substrate uniformity, each of the target substrates having a surface area with a certain ratio relative to the reference surface area; and   determining actual conditions of the oxidation process to be used for the target substrates from the reference conditions, while adjusting essentially merely a process time thereof, as a function of the certain ratio.   
     
     
         19 . The method according to  claim 18 , wherein the inter-substrate uniformity is determined with reference to inter-substrate uniformity of thickness of a film formed by the oxidation process. 
     
     
         20 . The method according to  claim 18 , wherein the reference conditions include flow rates of the oxidizing gas and the deoxidizing gas.