Advanced multi-pressure workpiece processing

Abstract

Workpiece processing uses a transfer chamber in cooperation with a process chamber. The workpiece is to be heated to a treatment temperature, at a preheating pressure, and subsequently exposed to a plasma at a treatment pressure, which is less than the preheating pressure. The process chamber pressure does not exceed the preheating pressure, yet very rapid pressure increases can be induced in the process chamber in transitioning from the treatment pressure to the preheating pressure. The transfer chamber pressure can be maintained at the treatment pressure, the preheating pressure or raised to a selected pressure to backfill the process chamber to the preheating pressure. A backfill arrangement can selectively induce rapid pressure increases in the process chamber. A bypass arrangement provides selective pressure communication between the transfer and process chambers and can be used for backfilling the process chamber from the transfer chamber.

1 . In a system for treating at least one workpiece using a treatment process, said system having at least a transfer chamber and a processing chamber such that a transfer chamber pressure, in the transfer chamber, and a processing chamber pressure, in the processing chamber, can each vary and the workpiece can be moved between the transfer chamber and the processing chamber, said system further including a process gas regulation arrangement for providing process gas to said processing chamber at least during a plasma treatment process at a given flow rate and which is capable of providing said process gas at a maximum flow rate, a method comprising: 
 a) equalizing the transfer chamber pressure and the processing chamber pressure to a treatment pressure at which the workpiece is to be subjected to a plasma treatment process;    b) transferring the workpiece from the transfer chamber to the processing chamber at the treatment pressure;    c) preheating the workpiece to a treatment temperature, in cooperation with raising the processing chamber pressure to a preheating pressure at a pressure rise rate resulting at least in part from using an additional process chamber gas input flow at an input flow rate which causes an overall input rate to the processing chamber to be greater than said maximum flow rate, without raising the transfer chamber pressure;    d) reducing the processing chamber pressure to the treatment pressure; and    e) exposing the workpiece to said plasma treatment process at least approximately at said treatment pressure and at said treatment temperature.    
   
   
       2 . The method of  claim 1  wherein said pressure rise rate is at least 15 Torr per second.  
   
   
       3 . The method of  claim 1  wherein said workpiece supports a photoresist layer and wherein said preheating and exposing cooperate in removing the photoresist layer using said plasma treatment process.  
   
   
       4 . The method of  claim 3  wherein said plasma treatment process produces a plasma which is customized for removing said photoresist layer from the substrate at said treatment temperature.  
   
   
       5 . The method of  claim 1  wherein said workpiece is supported by a susceptor and including heating the susceptor for use in preheating the workpiece.  
   
   
       6 . The method of  claim 5  wherein heating includes heating the susceptor to an at least approximately fixed temperature.  
   
   
       7 . The method of  claim 1  wherein said treatment pressure is in a range from approximately 0.01 to 10 Torr.  
   
   
       8 . The method of  claim 1  wherein said treatment pressure is approximately 1 Torr.  
   
   
       9 . The method of  claim 1  wherein said preheating pressure is in a range from approximately 25 to 250 Torr.  
   
   
       10 . The method of  claim 1  wherein said preheating pressure is at least approximately 60 Torr.  
   
   
       11 . The method of  claim 1  wherein preheating includes introducing a preheating gas mixture into the processing chamber for enhancing a rate of temperature increase of the workpiece.  
   
   
       12 . The method of  claim 11  including using helium gas as at least a portion of the preheating gas mixture.  
   
   
       13 . The method of  claim 1  including configuring a backfill reservoir arrangement for selective pressure communication with said processing chamber for use in selectively producing a pressure increase in said processing chamber by causing said additional process chamber input flow, and preheating the workpiece in cooperation with raising the processing chamber pressure includes backfilling the processing chamber to said preheating pressure using the additional process chamber gas input flow from the backfill reservoir arrangement.  
   
   
       14 . The method of  claim 13  wherein backfilling includes using a gas diffuser for introducing the additional process chamber gas input flow into the processing chamber from said backfill reservoir arrangement.  
   
   
       15 . The method of  claim 14  including generating a plasma, as part of said plasma treatment process, using the process gas, and the gas diffuser is further used for introducing the process gas into the processing chamber.  
   
   
       16 . The method of  claim 13  wherein said backfill reservoir arrangement is configured to include a backfill reservoir and storing a backfill gas in the backfill reservoir at a pressure that is greater than a target pressure to which the processing chamber is to be backfilled.  
   
   
       17 . The method of  claim 16  wherein the target pressure is selected as the preheating pressure for use during heating the workpiece and heating the workpiece to a treatment temperature for subsequent use during treating the workpiece.  
   
   
       18 . The method of  claim 13  including causing a backfill pressure in the backfill reservoir to rise to a selected value, with the processing chamber at a treatment pressure that is lower than the selected value and which treatment pressure is also lower than a preheating pressure at which the workpiece is to be heated to a treatment temperature and, thereafter, backfilling includes placing the backfill reservoir in pressure communication with the processing chamber in a way which causes the backfill pressure and the treatment chamber pressure to equalize at least approximately to the preheating pressure for subsequent use in enhancing a heating rate of the workpiece.  
   
   
       19 . The method of  claim 18  wherein said process gas regulation arrangement provides at least approximately no process gas during said backfilling.  
   
   
       20 . The method of  claim 13  wherein said pressure rise rate in the processing chamber is in a range of approximately 15 to 150 Torr per second.  
   
   
       21 . The method of  claim 13  wherein backfilling includes inducing said pressure rise rate in the processing chamber at approximately 30 Torr per second.  
   
   
       22 . The method of  claim 1  including simultaneously treating a pair of workpieces according to steps (a) through (e).  
   
   
       23 . The method of  claim 1  including processing a series of workpieces according to steps (a) through (e).  
   
   
       24 . In a system for treating at least one workpiece, said system having at least a transfer chamber and a processing chamber such that a transfer chamber pressure, in the transfer chamber, and a processing chamber pressure, in the processing chamber, can each vary and the workpiece can be moved between the transfer chamber and the processing chamber, said system further including a process gas regulation arrangement for providing process gas to said processing chamber at least during a plasma treatment process at a given flow rate and which is capable of providing said process gas at a maximum flow rate, an apparatus comprising: 
 a first arrangement at least for controlling the processing chamber pressure to reduce the processing chamber pressure to a treatment pressure at which the workpiece is to be subjected to a plasma treatment process and for selectively raising the processing chamber pressure, in cooperation with said process gas regulation arrangement, to a preheating pressure, which is higher than the treatment pressure, at a pressure rise rate resulting at least in part from using an additional process chamber gas input flow at an input flow rate which causes an overall input rate to the processing chamber to be greater than said maximum flow rate, without raising the transfer chamber pressure; and    a second arrangement in said processing chamber for preheating the workpiece to a treatment temperature in cooperation with raising the processing chamber pressure from said treatment pressure to said preheating pressure, using said first arrangement, and with said transfer chamber pressure remaining, at least approximately, at said treatment pressure such that the processing chamber pressure can then be reduced to the treatment pressure and the workpiece exposed to said plasma treatment process at least approximately at said treatment pressure and at said treatment temperature.    
   
   
       25 . In a system for treating at least one workpiece, said system having at least a transfer chamber and a processing chamber such that a transfer chamber pressure, in the transfer chamber, and a processing chamber pressure, in the processing chamber, can each be controlled and the workpiece can be moved between the transfer chamber and the processing chamber, said system further including a process gas regulation arrangement for providing process gas to said processing chamber at least during a plasma treatment process at a given flow rate and which is otherwise capable of providing said process gas at a maximum flow rate, a method comprising: 
 manipulating at least the processing chamber pressure and cooperatively moving the workpiece between the transfer chamber and the processing chamber such that the workpiece is exposed to a preheating pressure in the processing chamber for use in heating the workpiece to a treatment temperature and so that the workpiece is subjected to a treatment process in the processing chamber, at least approximately at a treatment pressure that is lower than the preheating pressure, after having at least approximately reached the treatment temperature, in a way which produces a maximum processing chamber pressure of no more than approximately the preheating pressure using a value of the preheating pressure that is less than atmospheric pressure, and using a rate of pressure increase in the processing chamber from the treatment pressure to the preheating pressure resulting at least in part from using an additional process chamber gas input flow at an input flow rate which causes an overall input rate to the processing chamber to be greater than said maximum flow rate, without raising the transfer chamber pressure.