Systems and methods for oscillating exposure of a semiconductor workpiece to multiple chemistries

Abstract

Systems and methods for oscillating exposure of a semiconductor workpiece to multiple chemistries are disclosed. A method in accordance with one embodiment includes sequentially exposing a portion of a semiconductor workpiece surface to a first chemistry having a first chemical composition and a second chemistry having a second chemical composition different than the first. Prior to rinsing the portion of the workpiece surface, the portion is sequentially exposed to the first and second chemistries again. The first and second chemistries are removed from the portion, and, after sequentially exposing the portion to each of the first and second chemistries at least twice, and removing the first and second chemistries, the portion is rinsed and dried.

1 . An apparatus for processing a semiconductor workpiece, comprising:
 a workpiece support;   a process head, at least one of the workpiece support and the process head being linearly movable relative to the other, the process head including at least one fluid delivery port and at least one fluid removal port;   a valve coupled in fluid communication with a first source of chemistry, a second source of chemistry, and the at least one fluid delivery port; and   a controller operatively coupled to the valve and programmed with instructions directing the valve to change between a first state and a second state at intervals of ten seconds or less, with the valve in the first state directing first fluid from the first source to exit through the process head, and with the valve in the second state directing second fluid from the second source to exit through the process head.   
     
     
         2 . The apparatus of  claim 1  wherein the controller is programmed with instructions directing the valve to change between the first state and the second state at intervals of two seconds or less. 
     
     
         3 . The apparatus of  claim 1  wherein the valve is carried by the process head. 
     
     
         4 . The apparatus of  claim 1  wherein the valve includes a rotary valve. 
     
     
         5 . The apparatus of  claim 1  wherein the valve directs both the first and second fluids to exit through the same fluid delivery port. 
     
     
         6 . The apparatus of  claim 1  wherein the valve directs the first fluid through a first fluid delivery port and the second fluid through a second fluid delivery port different than the first. 
     
     
         7 . The apparatus of  claim 1  wherein the valve is one of two valves, with a first valve coupled to the first source and a second valve coupled to the second source, each of the first and second valves being changeable between a first state in which the valve is closed and a second state in which the valve is open. 
     
     
         8 . The apparatus of  claim 1 , further comprising the first source and the second source, and wherein the first source includes a first liquid having a first pH and the second source includes a second liquid having a second pH different than the first pH. 
     
     
         9 . The apparatus of  claim 8  wherein one of the first and second liquids has a pH less than 5 and the other of the first and second fluids has a pH greater than 7. 
     
     
         10 . An apparatus for processing a semiconductor workpiece, comprising:
 a workpiece support;   a process head, at least one of the workpiece support and the process head being linearly movable relative to the other along a motion axis, the process head including multiple pairs of fluid delivery ports arranged along the motion axis, with each pair including at least one first fluid delivery port coupled to a source of a first chemistry, at least one second fluid delivery port coupled to a source of a second chemistry, and at least one fluid removal port positioned between the at least one first fluid delivery port and the at least one second fluid delivery port; and   a controller operatively coupled to the head and the support and programmed with instructions directing the relative movement between the head and the support while the at least one fluid removal port, the at least one first fluid delivery port, and the at least one second fluid delivery port are simultaneously active.   
     
     
         11 . The apparatus of  claim 10  wherein the controller is programmed with instructions to vary a frequency with which a point on a workpiece carried by the support is exposed to the first and second chemistries by controlling a relative speed between the head and the support. 
     
     
         12 . The apparatus of  claim 10  wherein the controller is programmed with instructions to control the number of active pairs of fluid delivery ports.