Ashing device

Abstract

An ashing device that prevents the ashing rate from changing over time. The ashing device ashes organic material on a substrate including an exposed metal in a processing chamber. The ashing device includes a path, which is formed in the processing chamber and through which active species supplied to the processing chamber pass. The path is defined by a surface on which the metal scattered from the substrate by the active species is collectible, with the surface being formed so as to expose a metal that is of the same kind.

1 . An ashing device for ashing organic material on a substrate including an exposed metal in a processing chamber, the ashing device comprising:
 a path through which active species supplied to the processing chamber pass;   wherein the path is defined by a surface on which the metal scattered from the substrate by the active species is collectible, with the surface being formed so as to expose the same kind of metal as the metal exposed from the substrate.   
   
   
       2 . The ashing device according to  claim 1 , further comprising:
 a stage which holds the substrate; and   a diffusion plate attached to an inner surface of the processing chamber so as to face toward the stage and form a gap with the inner surface of the processing chamber, in which the diffusion plate diffuses the active species supplied to the processing chamber through the gap and includes a through hole through which the active species pass;   wherein the surface defining the path includes:
 at least part of the inner surface of the processing chamber that faces toward the substrate; and 
 a surface of the diffusion plate that faces toward the substrate. 
   
   
   
       3 . The ashing device according to  claim 2 , further comprising:
 a diffusion prevention wall which is cylindrical and which surrounds the diffusion plate, in which the diffusion prevention wall prevents unnecessary diffusion of the active species to the substrate held on the stage;   wherein the surface defining the path further includes an inner circumferential surface and bottom surface of the diffusion prevention wall.   
   
   
       4 . The ashing device according to  claim 3 , wherein the diffusion prevention wall is formed from the same kind of metal as the metal exposed from the substrate. 
   
   
       5 . The ashing device according to  claim 2 , wherein the processing chamber is formed from the same kind metal as the metal exposed from the substrate. 
   
   
       6 . The ashing device according to  claim 2 , wherein:
 the stage is connected to a high frequency power supply which applies a high frequency bias to the stage; and   the surface defining the path functions as an electrically opposite electrode of the stage.   
   
   
       7 . The ashing device according to  claim 2 , wherein the diffusion plate includes a surface supplied with the active species, and a passivation film is formed on the surfaced supplied with the active species. 
   
   
       8 . The ashing device according to  claim 7 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a metal oxide layer functioning as the passivation film being formed on the second surface. 
   
   
       9 . The ashing device according to  claim 7 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a fluoride layer functioning as the passivation film being formed on the second surface. 
   
   
       10 . The ashing device according to  claim 3 , wherein the processing chamber is formed from the same kind of metal as the metal exposed from the substrate. 
   
   
       11 . The ashing device according to  claim 10 , wherein:
 the stage is connected to a high frequency power supply which applies a high frequency bias to the stage; and   the surface defining the path functions as an electrically opposite electrode of the stage.   
   
   
       12 . The ashing device according to  claim 11 , wherein the diffusion plate includes a surface supplied with the active species, and a passivation film is formed on the surfaced supplied with the active species. 
   
   
       13 . The ashing device according to  claim 12 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a metal oxide layer functioning as the passivation film being formed on the second surface. 
   
   
       14 . The ashing device according to  claim 12 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a fluoride layer functioning as the passivation film being formed on the second surface. 
   
   
       15 . The ashing device according to  claim 3 , wherein:
 the stage is connected to a high frequency power supply which applies a high frequency bias to the stage; and   the surface defining the path functions as an electrically opposite electrode of the stage.   
   
   
       16 . The ashing device according to  claim 15 , wherein the diffusion plate includes a surface supplied with the active species, and a passivation film is formed on the surfaced supplied with the active species. 
   
   
       17 . The ashing device according to  claim 16 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a metal oxide layer functioning as the passivation film being formed on the second surface. 
   
   
       18 . The ashing device according to  claim 16 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a fluoride layer functioning as the passivation film being formed on the second surface. 
   
   
       19 . The ashing device according to  claim 3 , wherein the diffusion plate includes a surface supplied with the active species, and a passivation film is formed on the surfaced supplied with the active species. 
   
   
       20 . The ashing device according to  claim 19 , wherein the diffusion plate is a metal plate formed from the same kind of metal as the metal exposed from the substrate, in which the metal plate includes a first surface facing toward the substrate and a second surface supplied with the active species, with a metal oxide layer functioning as the passivation film being formed on the second surface.