Ion source cleaning in semiconductor processing systems

Abstract

Cleaning of an ion implantation system or components thereof, utilizing a reactive cleaning reagent enabling growth/etching of the filament in an ion source of the arc chamber, by appropriate control of temperature in the arc chamber to effect the desired filament growth or alternative filament etching. Also described is the use of reactive gases such as XeFx, WFx, AsFx, PFx and TaFx, wherein x has a stoichioimetrically appropriate value or range of values, for cleaning regions of ion implanters, or components of implanters, in in situ or ex situ cleaning arrangements, under ambient temperature, elevated temperature or plasma conditions. Among specific reactive cleaning agents, BrF3 is described as useful for cleaning ion implant systems or component(s) thereof, in in situ or ex situ cleaning arrangements. Also described is a method of cleaning the forelines of an ion implant system for at least partial removal of ionization-related deposit from said forelines, comprising contacting said forelines with a cleaning gas wherein said cleaning gas is chemically reactive with said deposit. Also described is a method of improving the performance and extending the lifetime of an ion implant system, comprising contacting the cathode with a gas mixture.

1 .- 49 . (canceled) 
     
     
         50 . A method of enhancing performance of an ion implantation tool, comprising periodically cleaning in situ at least one component of said ion implantation tool selected from the group consisting of (i) ion implant vacuum system forelines, (ii) ion implant vacuum system vacuum pumps, (iii) ion source turbo pumps, and (iv) ion source turbo pump forelines, by periodically contacting said at least one component with a cleaning composition that is effective to at least partially remove from said at least one component, material deposited thereon in ion implantation operation of the ion implantation tool, wherein periodicity of said contacting is according to a predetermined time cycle or in response to a determination of an operational variable indicative of deposition of material on said at least one component. 
     
     
         51 . The method of  claim 50 , wherein said at least one component of said ion implantation tool comprises an ion implant vacuum system foreline. 
     
     
         52 . The method of  claim 50 , wherein said at least one component of said ion implantation tool comprises an ion implant vacuum system vacuum pump. 
     
     
         53 . The method of  claim 50 , wherein said at least one component of said ion implantation tool comprises an ion source turbo pump. 
     
     
         54 . The method of  claim 50 , wherein said at least one component of said ion implantation tool comprises an ion source turbo pump foreline. 
     
     
         55 . The method of  claim 50 , wherein the cleaning composition comprises a cleaning agent selected from the group consisting of XeF 2 , XeF 4 , XeF 6 , GeF 4 , SiF 4 , BF 3 , AsF 5 , AsF 3 , PF 5 , PF 3 , F 2 , TaF 3 , TaF 5 , WF 6 , WF 5,  WF 4 , NF 3 , IF 5 , IF 7 , KrF 2 , SF 6 , C 2 F 6 , CF 4 , Cl 2 , HCl, ClF 3 , ClO 2 , N 2 F 4 , N 2 F 2 , N 3 F, NFH 2 , NH 2 F, HOBr, Br 2 , BrF 3 , C 3 F 8 , C 4 F 8 , C 5 F 8 , CHF 3 , CH 2 F 2 , CH 3 F, COF 2 , HF, C 2 HF 5 , C 2 H 2 F 4 , C 2 H 3 F 3 , C 2 H 4 F 2 , C 2 H 5 F, C 3 F 6 , COCl 2 , CCl 4 , CHCl 3 , CH 2 Cl 2 , and CH 3 Cl. 
     
     
         56 . The method of  claim 50 , wherein the cleaning composition comprises XeF 2 , N 2 F 4 , F 2 , or other fluorinated species which is reactive with said material deposited in ion implantation operation of the ion implantation tool. 
     
     
         57 . The method of  claim 50 , wherein the cleaning composition comprises XeF 2 . 
     
     
         58 . The method of  claim 57 , wherein periodicity of said contacting is according to a predetermined time cycle. 
     
     
         59 . The method of  claim 58 , wherein said contacting is carried out for a period of from 15 minutes to 30 minutes. 
     
     
         60 . The method of  claim 57 , wherein the XeF 2  is flowed through the component in the contacting, at a flow rate in a range of from 50 to 100 sccm. 
     
     
         61 . The method of  claim 57 , wherein the component is filled with XeF 2  to a first predetermined pressure for the contacting. 
     
     
         62 . The method of  claim 61 , wherein pressure in the component filled with XeF 2  is thereafter monitored until a second predetermined pressure is reached, whereupon the contacting is terminated. 
     
     
         63 . The method of  claim 61 , wherein temperature of the component filled with XeF 2  is thereafter monitored until a predetermined temperature is reached, whereupon the contacting is terminated. 
     
     
         64 . The method of  claim 57 , wherein the component comprises a foreline, and said contacting comprises continuous flow of the XeF 2  through the foreline. 
     
     
         65 . The method of  claim 57 , wherein the component comprises a foreline, the ion implantation tool further comprises a roughing pump and an ion source turbo pump, and said contacting comprises flow of the XeF 2  through the foreline with the turbo pump off and the roughing pump on. 
     
     
         66 . The method of  claim 57 , wherein the component comprises a foreline, and said contacting comprises repetitive pulsed flow and evacuation of the XeF 2 . 
     
     
         67 . The method of  claim 57 , wherein said XeF 2  is supplied for said contacting from a supply vessel positioned in a gas box of the ion implantation tool. 
     
     
         68 . The method of  claim 57 , wherein a xenon-containing effluent is produced by said contacting, and the xenon-containing effluent is processed for recovery of xenon therefrom. 
     
     
         69 . The method of  claim 57 , wherein the cleaning composition effects exothermic reaction with the deposited material, and the cleaning is monitored with a temperature detector.