Plasma Etching Chamber

Abstract

Disclosed is an apparatus of dry cleaning a film and particles deposited at a periphery of a wafer. The apparatus comprises a housing providing a space isolated from an outside and having an upper surface opened/closed by a cover; an upper electrode assembly mounted in the housing being separated from the cover so that its position is maintained when opening and closing the cover; a lower electrode assembly mounted below the upper electrode assembly to be moveable vertically in the housing; and means for moving the lower electrode assembly vertically. In addition, transparent observation windows are provided at a center of an upper assembly so that it is possible to check an alignment state of the wafer from the outside.

1 . A plasma etching chamber comprising:
 a housing providing a space isolated from an outside and having an upper surface opened and closed by a cover;   an upper electrode assembly mounted in the housing with being separated from the cover so that its position is maintained when opening and closing the cover;   a lower electrode assembly mounted below the upper electrode assembly to be moveable vertically in the housing, a wafer resting on the lower electrode assembly; and   means for moving the lower electrode assembly vertically.   
     
     
         2 . The plasma etching chamber according to  claim 1 , wherein the lower electrode assembly comprises a wafer chuck on which the wafer rests and a ring-shaped lower electrode that is disposed at a periphery of the wafer chuck. 
     
     
         3 . The plasma etching chamber according to  claim 1 , wherein the lower electrode assembly comprises a wafer chuck on which the wafer rests, and the wafer chuck is made of ceramics and has a space therein in which a center fan formed with poly-imide is accommodated. 
     
     
         4 . The plasma etching chamber according to  claim 2 , wherein a ring-shaped discharge electrode grounded via a switching means is mounted at an edge of the wafer chuck, and an electrostatic electrode to which power is applied through a DC generator is disposed in the center fan to chuck or de-chuck the wafer with electrostatic charges. 
     
     
         5 . The plasma etching chamber according to  claim 1 , further comprising an in-situ monitoring tool that is disposed in a vent passage of the housing and detects particles remaining in gases generated with the plasma etching, wherein the in-situ monitoring tool comprises a light-emitting part and a light-receiving part that are disposed to be opposite. 
     
     
         6 . The plasma etching chamber according to  claim 1 , wherein the upper electrode assembly rests on a step formed on a side wall of the housing and is fixed with an engagement means. 
     
     
         7 . The plasma etching chamber according to  claim 1 , wherein the vertically moving means comprises a shaft downwardly extending from the lower electrode assembly and protruding to an outside of the housing; a screw driven by a servo motor; a carrier vertically moving along the screw as the screw rotates; and a support rod connecting the shaft and the carrier. 
     
     
         8 . The plasma etching chamber according to  claim 1 , wherein a sealing is interposed between the housing and the cover. 
     
     
         9 . The plasma etching chamber according to  claim 1 , wherein a bellows for maintaining an air-tight state is further mounted to a periphery of the shaft. 
     
     
         10 . The plasma etching chamber according to  claim 1 , wherein the upper electrode assembly comprises an upper electrode body detachably mounted in the housing, a ring-shaped upper electrode fixedly attached to a bottom surface of the upper electrode body, a gas distribution plate forming a reaction gas passage at an inner side of the upper electrode, and a baffle plate forming an inert gas passage at a bottom surface of the gas distribution plate. 
     
     
         11 . The plasma etching chamber according to  claim 10 , wherein horizontal passages that communicate with the outside and the inert gas passage are provided to a sidewall of the housing and the upper electrode body. 
     
     
         12 . The plasma etching chamber according to  claim 10 , wherein an introduction hole through which the reaction gas is introduced is formed at an upper sidewall of the housing and the reaction gas is directly introduced to the reaction gas passage through a vertical passage formed at the upper electrode body. 
     
     
         13 . The plasma etching chamber according to  claim 6 , wherein the engagement means comprises a bolt or a pin, and a through-hole through which the bolt or pin passes is formed at the upper electrode assembly, and a size of the through-hole is larger than that of the bolt or pin. 
     
     
         14 . A plasma etching chamber comprising:
 a housing providing a space isolated from an outside and having an upper surface opened and closed by a cover;   an upper electrode assembly mounted in the housing;   a lower electrode assembly mounted below the upper electrode assembly to be moveable vertically in the housing, a wafer resting on the lower electrode assembly;   means for moving the lower electrode assembly vertically; and   a transparent observation window provided at a center of the upper electrode assembly.   
     
     
         15 . The plasma etching chamber according to  claim 14 , wherein a transparent observation window is further provided at a center of an upper surface of the housing. 
     
     
         16 . The plasma etching chamber according to  claim 14 , wherein a CCD camera is further provided above the observation window formed on the center of the upper electrode assembly. 
     
     
         17 . The plasma etching chamber according to  claim 15 , wherein a CCD camera is further provided above the observation window formed on the center of the upper surface of the housing. 
     
     
         18 . The plasma etching chamber according to  claim 14 , wherein an alignment mark is respectively formed on a center of the observation window and a center of the lower electrode assembly, so that an alignment of the upper and lower electrode assemblies is checked according to whether the alignment marks are matched each other. 
     
     
         19 . The plasma etching chamber according to  claim 18 , wherein the alignment mark is cross-shaped. 
     
     
         20 . The plasma etching chamber according to  claim 14 , wherein the transparent material includes quartz or sapphire. 
     
     
         21 . The plasma etching chamber according to  claim 3  wherein a ring-shaped discharge electrode grounded via a switching means is mounted at an edge of the wafer chuck, and an electrostatic electrode to which power is applied through a DC generator is disposed in the center fan to chuck or de-chuck the wafer with electrostatic charges.