Multi-Station Sputtering and Cleaning System

Abstract

A multi-chamber processing system is described for depositing materials on multiple workpieces (wafers, display panels, or any other workpieces) at a time in a vacuum chamber. The system includes a sputtering chamber and a separate pre-clean chamber, where wafers can be transferred between the two chambers by a robotic arm without breaking a vacuum. The wafers are mounted one-by-one onto a rotating first pallet in the pre-cleaning chamber through a single entrance/exit port. After a batch cleaning, the robotic arm transfers the wafers one-by-one to a rotating second pallet in a sputtering chamber through a single entrance/exit, where the wafers are subjected to a batch sputtering process. After the sputtering process, the robotic arm transfers the wafers one-by-one to a load lock.

1 . A method performed by a processing system comprising:
 receiving a plurality of workpieces in at least one first location;   creating a low pressure in the at least one first location significantly below ambient pressure;   rotating a first pallet in a cleaning chamber to successively align individual workpiece support areas on the first pallet with a first entrance into the cleaning chamber, each workpiece support area only supporting a single workpiece;   controlling a robotic arm in a transport module to move workpieces, one at a time, from the at least one first location to associated workpiece support areas on the first pallet through the first entrance into the cleaning chamber while the first pallet rotates to successively align the workpiece support areas with the first entrance into the cleaning chamber and while the at least one first location, the transport module, and the cleaning chamber are at the low pressure, the robotic arm only placing one workpiece over an associated workpiece support area;   controlling the cleaning chamber to etch all workpieces on the first pallet, while the workpieces are supported on the first pallet, for batch cleaning of the workpieces using a plasma,   wherein no additional workpieces are introduced into the cleaning chamber, and no workpieces are removed from the cleaning chamber, until batch cleaning of all the workpieces on the first pallet has been completed;   after the batch cleaning of all the workpieces in the cleaning chamber is completed, rotating the first pallet in the cleaning chamber to successively align each workpiece support area with the first entrance to the cleaning chamber while the robotic arm transports the workpieces, one at a time, from the first pallet to a rotating second pallet in a sputtering chamber through a second entrance into the sputtering chamber while the second pallet rotates to successively align workpiece support areas on the second pallet with the second entrance for receiving associated workpieces from the robotic arm and while the cleaning chamber, the transport module, and the sputtering chamber are at the low pressure, each workpiece support area on the second pallet only supporting a single workpiece, the robotic arm only placing one workpiece over an associated workpiece support area on the second pallet,   the sputtering chamber comprising at least one target for sputtering target material onto the workpieces using a plasma;   batch sputtering target material on the workpieces while the workpieces are supported on the second pallet,   wherein no additional workpieces are introduced into the sputtering chamber, and no workpieces are removed from the sputtering chamber, until batch sputtering on all the workpieces on the second pallet has been completed; and   after the batch sputtering, rotating the second pallet in the sputtering chamber to successively align each workpiece support area on the second pallet with the second entrance to the sputtering chamber while the robotic arm transports the workpieces, one at a time, from the second pallet to a different location.   
     
     
         2 . The method of  claim 1  wherein a base pressure in the cleaning chamber is lower than a pressure in the transport module during a cleaning operation. 
     
     
         3 . The method of  claim 1  wherein a base pressure in the sputtering chamber is lower than a pressure in the transport module during a sputtering operation. 
     
     
         4 . The method of  claim 1  wherein the workpieces are wafers. 
     
     
         5 . The method of  claim 1  wherein the workpieces are semiconductor substrates. 
     
     
         6 . The method of  claim 1  wherein there are the same number of workpiece support areas on the first pallet and second pallet. 
     
     
         7 . The method of  claim 1  wherein there are at least four workpiece support areas on the first pallet and second pallet. 
     
     
         8 . The method of  claim 1  further comprising:
 extending a plurality of pins from each of the workpiece support areas of the first pallet and the second pallet as each workpiece support area is aligned with the first entrance and the second entrance to temporarily support a workpiece delivered by the robotic arm through the first entrance and the second entrance; and 
 withdrawing the pins into the workpiece support areas after the robotic arm has positioned a workpiece on the pins to cause the workpiece to rest on an associated workpiece support area of the first pallet and second pallet. 
 
     
     
         9 . The method of  claim 1  wherein controlling the cleaning chamber to etch all workpieces on the pallet for batch cleaning of the workpieces using a plasma comprises creating an inductively coupled plasma in the cleaning chamber. 
     
     
         10 . The method of  claim 1  wherein the different location is the at least one first location. 
     
     
         11 . The method of  claim 1  wherein the different location is also at the low pressure. 
     
     
         12 . The method of  claim 1  wherein the at least one target is a plurality of targets, and the second pallet rotates to position the workpieces under different targets for sputtering different materials onto the workpieces. 
     
     
         13 . A processing system comprising:
 at least one first location containing a plurality of workpieces;   a cleaning chamber having a first entrance;   a first pallet in the cleaning chamber that is controllable to rotate to successively align individual workpiece support areas on the first pallet with the first entrance into the cleaning chamber, each workpiece support area only supporting a single workpiece, wherein a plurality of workpieces are simultaneously supported by the first pallet;   a transport module;   a robotic arm in the transport module controllable to move workpieces, one at a time, from the at least one first location to associated workpiece support areas on the first pallet through the first entrance into the cleaning chamber while the first pallet rotates to successively align the workpiece support areas with the first entrance into the cleaning chamber and while the at least one first location, the transport module, and the cleaning chamber are at a low pressure, the robotic arm being controllable to only place one workpiece over an associated workpiece support area;   the cleaning chamber being controllable to etch all workpieces on the first pallet, while the workpieces are supported on the first pallet, for batch cleaning of the workpieces using a plasma;   the robotic arm being controllable such that no additional workpieces are introduced into the cleaning chamber, and no workpieces are removed from the cleaning chamber, until batch cleaning of all the workpieces on the first pallet has been completed;   a sputtering chamber;   a second pallet in the sputtering chamber that is controllable to rotate to successively align individual workpiece support areas on the second pallet with a second entrance into the sputtering chamber, each workpiece support area on the second pallet only supporting a single workpiece, wherein a plurality of workpieces are simultaneously supported by the second pallet;   after the batch cleaning of all the workpieces in the cleaning chamber, the first pallet in the cleaning chamber being controllable to rotate to successively align each workpiece support area with the first entrance to the cleaning chamber while the robotic arm is controllable to transport the workpieces, one at a time, from the first pallet to the second pallet through the second entrance of the sputtering chamber while the second pallet rotates to successively align workpiece support areas on the second pallet with the second entrance for receiving associated workpieces from the robotic arm and while the cleaning chamber, the transport module, and the sputtering chamber are at the low pressure, each workpiece support area on the second pallet only supporting a single workpiece, the robotic arm being controllable to only place one workpiece over an associated workpiece support area on the second pallet,   the sputtering chamber comprising at least one target for sputtering target material onto the workpieces using a plasma so as to batch sputter target material on the workpieces while the workpieces are supported on the second pallet;   wherein the robotic arm is controllable such that no additional workpieces are introduced into the sputtering chamber, and no workpieces are removed from the sputtering chamber, until batch sputtering on all the workpieces on the second pallet has been completed; and   wherein the robotic arm and second pallet are controllable such that, after the batch sputtering, the second pallet in the sputtering chamber rotates to successively align each workpiece support area on the second pallet with the second entrance to the sputtering chamber while the robotic arm transports the workpieces, one at a time, from the second pallet to a different location.   
     
     
         14 . The system of  claim 13  wherein the workpieces are wafers. 
     
     
         15 . The system of  claim 13  wherein the workpieces are semiconductor substrates. 
     
     
         16 . The system of  claim 13  wherein there are the same number of workpiece support areas on the first pallet and second pallet. 
     
     
         17 . The system of  claim 13  wherein there are at least four workpiece support areas on the first pallet and second pallet. 
     
     
         18 . The system of  claim 13  wherein the different location is the at least one first location. 
     
     
         19 . The system of  claim 13  wherein the different location is also at the low pressure. 
     
     
         20 . The system of  claim 13  wherein the at least one target is a plurality of targets, and the second pallet rotates to position the workpieces under different targets for sputtering different materials onto the workpieces.