Sputtering apparatus

Abstract

The present invention provides a means capable of determining the surface state of the target to execute accurate and quick cleaning of necessary part. The means includes: a magnet unit capable of forming a magnetic field on the surface of a target; a rotary system capable of driving the magnet unit of change the magnetic field pattern; and an ammeter configured to measure target current when the magnetic field is formed by the magnet unit and discharge voltage is applied to a target electrode to which the target is attached. The position of the magnet unit is variously changed by the rotary system, and the target current is measured at each position and compared with a reference value. It is then determined whether cleaning is necessary at each position, so that cleaning can be performed only for necessary part.

1 . A sputtering apparatus, comprising:
 a magnet unit capable of forming a magnetic field on a surface of a target;   a changing unit capable of driving the magnet unit to change a magnetic field pattern including a position and intensity of the magnetic field formed on the surface of the target;   a discharge state measuring unit configured to measure a discharge stare value when discharge voltage is applied to a target electrode to which the target is attached;   a memory unit configured to store a reference discharge state value acquired corresponding to each magnetic field pattern producible by the changing unit;   a determination unit configured to determine a state of the surface of the target based on a comparison between the discharge state value measured by the discharge state measuring unit at a first magnetic field pattern and a discharge state reference value corresponding to the first magnetic field pattern stored in the memory unit; and   a controller configured to select a second magnetic field pattern, which is different from the first magnetic field pattern, based on the result of determination by the determination unit, control the changing unit to produce the second magnetic field pattern, and execute sputter cleaning,   
     
     
         2 . The sputtering apparatus according to  claim 1 , wherein the second magnetic field pattern is selected so that an erosion pattern in which the surface of the target is removed with the first magnetic field pattern cancels out an erosion pattern in which the surface of the target is removed with the second magnetic field pattern. 
     
     
         3 . The sputtering apparatus according to  claim 1 , wherein the controller sets discharge power at measurement of a discharge state value by the discharge state measuring unit smaller than that at execution of sputter cleaning based on the result of determination by the determination unit. 
     
     
         4 . The sputtering apparatus according to  claim 1 , wherein the changing unit revolves the magnet unit around the central axis of the target at discharge to form a magnetic field moving along the target and changes the radius of the revolution to change the magnetic field pattern. 
     
     
         5 . The sputtering apparatus according to  claim 1 , wherein the changing unit changes a distance between the magnetic unit and the target to change the magnetic field pattern. 
     
     
         6 . The sputtering apparatus according to  claim 1 , wherein the discharge state measuring unit measures current flowing through the target as the discharge state value. 
     
     
         7 . The sputtering apparatus according to  claim 1 , wherein the discharge state reference value stored in the memory unit is a discharge state value measured by the discharge state measuring unit using an unused target. 
     
     
         8 . The sputtering apparatus according to  claim 1 , wherein the determination unit determines that sputter cleaning for the target is required when the discharge state value is out of a predetermined range around the discharge state reference value.