Plasma processing apparatus and method of cleaning the apparatus

Abstract

A plasma processing apparatus comprises a plasma generating chamber including a side wall and a roof-plate to cover the upper part of the side wall, in which plasma is generated; a plurality of magnets, one group of the magnets being arranged on the roof-plate in concentric circles, with the polarity of each magnets in each circle being alternated, and the other group of the magnets being arranged around the side wall of the plasma generating chamber in rings, with the polarity of each magnet in each ring being alternated, to form a cusped magnetic field to confine the plasma in the plasma generating chamber; and a holding device which is provided in the plasma generating chamber, to hold a substrate to be processed with the plasma; wherein the magnet means arranged on the roof-plate and the magnet means arranged around the side wall are held in such a way that then can be moved up and down.

What is claimed is:  
     
         1 . A plasma processing apparatus comprising: 
 a plasma generating chamber in which plasma is generated;    magnet means including a plurality of magnets which are arranged around said plasma generating chamber, with the polarity of each magnet being alternated, to form a cusped magnetic field to confine said plasma in said plasma generating chamber; and    holding means which is provided in said plasma generating chamber, for holding a substrate to be processed with said plasma;    wherein said magnet means is movably held such that it can move said formed cusped magnetic field.    
     
     
         2 . A plasma processing apparatus comprising: 
 a plasma generating chamber including a substantially cylindrical side wall and a roof-plate to cover the upper part of said side wall, in which plasma is generated;    a plurality of magnets, one group of said magnets being arranged on said roof-plate in concentric circles, with the polarity of each magnet in each circle being alternated, and the other group of said magnets being arranged around said side wall of said plasma generating chamber in rings, with the polarity of each magnet in each ring being alternated, to form a cusped magnetic field to confine said plasma in said plasma generating chamber; and    holding means which is provided in said plasma generating chamber, for holding a substrate to be processed with said plasma;    wherein said magnet means arranged on said roof-plate and said magnet means arranged around said side wall are movably held such that they can be moved up and down.    
     
     
         3 . A plasma processing apparatus according to    claim 2   , wherein said group of said permanent magnets arranged on said roof-plate is supported by a moving mechanism which moves up and down, and said other group of said permanent magnets arranged around said side wall of said plasma generating chamber is supported by a swing mechanism to reciprocally move said other group of said permanent magnets up and down.  
     
     
         4 . A plasma processing apparatus comprising: 
 a plasma generating chamber including a substantially cylindrical side wall and a roof-plate to cover the upper part of said side wall, in which plasma is generated;    a plurality of magnets, one group of said magnets being arranged on said roof-plate in concentric circles, with the polarity of each magnets in each circle being alternated, and the other group of said magnets being arranged around said side wall of said plasma generating chamber in rings, the polarity of each magnet in each ring being alternated, to form a cusped magnetic field to confine said plasma in said plasma generating chamber; and    holding means which is provided in said plasma generating chamber, for holding a substrate to be processed with said plasma;    wherein said group of said permanent magnets arranged on said roof-plate is rotatably held eccentric to the central axis of said plasma generating chamber, and said other group of said permanent magnets arranged around said side wall of said plasma generating chamber is movably held such that is can be moved up and down.    
     
     
         5 . A plasma processing apparatus comprising: 
 a plasma generating chamber including a substantially cylindrical side wall and a roof-plate to cover the upper part of said side wall, in which plasma is generated;    a plurality of magnets, one group of said magnets being arranged on said roof-plate in concentric circles, with the polarity of each magnet in each circle being alternated, and the other group of said magnets being arranged around said side wall of said plasma generating chamber in rings, with the polarity of each magnet in each ring being alternated, to form a cusped magnetic field to confine said plasma in said plasma generating chamber; and    holding means which is provided in said plasma generating chamber, for holding a substrate to be processed with said plasma;    wherein said group of said permanent magnets arranged on said roof-plate are composed so that the magnetic field strength is alternately changed in the peripheral direction, with being rotatably held, and said other group of said permanent magnets arranged around said side wall of said plasma generating chamber is movably held such that it can be moved up and down.    
     
     
         6 . A plasma processing apparatus comprising: 
 a microwave generating source;    a vacuum chamber into which a microwave is introduced from said microwave generating source;    a magnetic field generating coil for generating a magnetic field to generate plasma by using electron cyclotron resonance with said microwave:    a plurality of permanent magnets arranged around said vacuum chamber with alternating polarities for each of said magnets, for confining said plasma; and    holding means which is provided in said vacuum chamber, for holding a substrate to be processed with said plasma;    wherein at least one of said magnetic field generating coil and said plurality of said permanent magnets is movably held such that it can be moved up and down.    
     
     
         7 . A plasma processing apparatus comprising: 
 a vacuum chamber with a dome in the side wall of said chamber, a roof-plate being located on the upper part of said side wall;    plasma inducing coils arranged around said side wall; and    holding means which is provided in said vacuum chamber, for holding a substrate to be processed with said plasma generated by said plasma inducing coils;    wherein a plurality of permanent magnets to confine said plasma is arranged outside said plasma inducing coils, with the polarity of each of said permanent magnets being alternated, and is movably held such that it can be moved.    
     
     
         8 . A method of cleaning the inside of a plasma processing chamber, comprising the steps of: 
 forming a cusped magnetic field with a plurality of permanent magnets arranged around said plasma processing chamber, with the polarity of each of said permanent magnets being alternated;    confining plasma generated in said chamber with said cusped magnetic field; and    removing deposits adhering to the inside wall of said chamber by moving the cusp points of said cusped magnetic field.    
     
     
         9 . A method of cleaning the inside of a plasma processing chamber, comprising the steps of: 
 forming a cusped magnetic field with a plurality of permanent magnets arranged around said plasma processing chamber, with the polarity of each of said permanent magnets being alternated;    confining plasma generated in said chamber with said cusped magnetic field; and    removing deposits adhering to the inside wall of said chamber by injecting ions in said plasma, while moving the cusp points of said cusped magnetic field, which contact the inside wall of said chamber.