Film forming method, film forming apparatus and control unit for the film forming apparatus

Abstract

The invention reduces generation of particles. An embodiment of the preset invention includes a target holder ( 6 ) for holding a target ( 4 ), a power source ( 12 ) for applying a power to the target holder ( 6 ), a substrate holder ( 7 ), a first shutter ( 14 ) capable of opening and closing between the target ( 4 ) and the substrate holder ( 7 ), a second shutter ( 19 ) located closer to the substrate holder ( 7 ) than to the first shutter ( 14 ), and capable of opening and closing between the target holder ( 6 ) and the substrate holder ( 7 ), and a controller (con) for controlling the power source ( 12 ) and the first and second shutters ( 14 ), ( 19 ). The controller (con) applies a first power to the target holder ( 6 ) in the state where the first shutter ( 14 ) is closed, then opens the first shutter ( 14 ), and further applies a second power higher than the first power to the target holder ( 6 ) in the state where the second shutter ( 19 ) is closed.

1 . A film forming method for forming a film on a substrate by sputtering a target, the method comprising:
 a first step of applying a first power to a target holder holding the target to cause discharge in a first discharge space, the first power being lower than a film forming power applied upon film formation from a power source connected to the target holder;   a second step of changing the location of discharging from the first discharge space to a second discharge space larger than the first discharge space while continuing the discharge caused in the first step;   a third step of applying a second power higher than the first power to the target holder from the power source in the second discharge space; and   a fourth step of exposing the substrate, which is shielded against the second discharge space, to the second discharge space.   
     
     
         2 . The film forming method according to  claim 1 , wherein:
 the first discharge space is formed when a first shielding member is located at a first position, the first shielding member being movable between the first position that shields between the target holder and a substrate holder holding the substrate and a second position that does not shield between the target holder and the substrate holder; and   in the second step, the first shielding member is moved from the first position to the second position.   
     
     
         3 . The film forming method according to  claim 1 , wherein:
 prior to the fourth step, the substrate is shielded against the second discharge space by a second shielding member which is movable between a third position that shields between the target holder and the substrate holder and a fourth position that does not shield between the target holder and the substrate holder; and   in the fourth step, the second shielding member is moved from the third position to the fourth position.   
     
     
         4 . The film forming method according to  claim 1 , wherein in the third step, a power applied to the target holder is increased from the first power to the second power. 
     
     
         5 . The film forming method according to  claim 4 , wherein in the third step, the power applied to the target holder is increased stepwise or continuously. 
     
     
         6 . The film forming method according to  claim 1 , wherein after the fourth step, the film is continuously formed on the substrate. 
     
     
         7 . A film forming apparatus comprising:
 a target holder for holding a target;   a power applying means for applying a power to the target holder;   a substrate holder for holding a substrate;   a shield which is grounded, has a hollow portion formed so as to surround the target holder, and has an opening formed for causing the hollow portion to communicate with outside the shield;   a first shielding member configured to be movable between a first position that shields between the target holder and the substrate holder by covering the opening and a second position that does not shield between the target holder and the substrate holder;   a second shielding member configured to be movable between a third position that shields between the target holder and the substrate holder by covering at least a substrate holding surface of the substrate holder and a fourth position that does not shield between the target holder and the substrate holder; and   a control means for controlling the power applying means and movement of the first and second shielding members, wherein   the control means controls the power applying means so as to apply a first power lower than a film forming power applied to the target holder upon film formation in a state where the first shielding member is located at the first position and the second shielding member is located at the third position, then controls movement of the first shielding member so as to move the first shielding member from the first position to the second position in a state where the second shielding member is located at the third position, and then controls the power applying means so as to apply a second power higher than the first power to the target holder.   
     
     
         8 . The film forming apparatus according to  claim 7 , wherein:
 the shield has conductivity; and   a surface of a hollow portion of the shield facing the target holder is coated with an insulating film formed through thermal spray.   
     
     
         9 . The film forming apparatus according to  claim 7 , wherein
 the control means controls, when the second power is applied, the power applying means so as to increase a power applied to the target holder from the first power to the second power.   
     
     
         10 . A control unit for controlling a film forming apparatus provided with a target holder for holding a target, a power applying means for applying a power to the target holder, a substrate holder for holding a substrate, a shield which is grounded, has a hollow portion formed so as to surround the target holder, and has an opening for causing the hollow portion to communicate with outside the shield; a first shielding member configured to be movable between a first position that shields between the target holder and the substrate holder by covering the opening and a second position that does not shield between the target holder and the substrate holder; and a second shielding member configured to be movable between a third position that shields between the target holder and the substrate holder by covering at least a substrate holding surface of the substrate holder and a fourth position that does not shield between the target holder and the substrate holder, the control unit comprising:
 a means for controlling the power applying means so as to apply a first power lower than a film forming power applied to the target holder upon film formation in a state where the first shielding member is located at the first position and the second shielding member is located at the third position;   a means for controlling movement of the first shielding member so as to move the first shielding member from the first position to the second position in a state where the second shielding member is located at the third position by applying the first power to the target holder while continuing discharge caused in a first discharge space between the hollow portion and the first shielding member; and   a means for controlling the power applying means so as to apply a second power higher than the first power to the target holder in a state where the first shielding member is located at the second position and the second shielding member is located at the third position.   
     
     
         11 . A computer program causing a computer to function as the control unit according to  claim 10 . 
     
     
         12 . A storage medium for storing a computer readable program, which stores the computer program according to  claim 11 .