Apparatus for etching substrate and method of fabricating thin-glass substrate

Abstract

Methods of fabricating devices including a TFT array substrate are provided. For example, a method of fabricating a TFT array substrate may comprise adhering a protection film onto an upper surface of a glass substrate containing silicon dioxide as a principal constituent on which a thin film transistor (TFT) array has been fabricated; and etching the glass substrate through a lower surface thereof such that the glass substrate has a thickness greater than 0 micrometer, but equal to or smaller than 200 micrometers. The etching may comprise preparing an apparatus for etching a substrate; and etching said glass substrate at an etching rate equal to or higher than 2 micrometers per a minute by means of the apparatus.

What is claimed is: 
     
         1 . A method of fabricating a TFT array substrate, comprising:
 (A) adhering a protection film onto an upper surface of a glass substrate containing silicon dioxide as a principal constituent on which a thin film transistor (TFT) array has been fabricated; and   (B) etching said glass substrate through a lower surface thereof such that said glass substrate has a thickness greater than 0 micrometer, but equal to or smaller than 200 micrometers,   said step (B) comprising:   preparing an apparatus for etching a substrate; and   etching said glass substrate at an etching rate equal to or higher than 2 micrometers per a minute by means of said apparatus,   said apparatus comprising:   (a) a nozzle system including at least one nozzle through which acid solution containing at least hydrofluoric acid is sprayed onto said substrate;   (b) a mover which moves at least one of said nozzle system and said substrate relative to the other in a predetermined direction in such a condition that said substrate and said nozzle system face each other;   (c) a filter system which filters off particles out of said acid solution having been sprayed onto said substrate, said filter system including:
 a container which temporarily contains said acid solution before said acid solution is supplied to said nozzle mechanism after said acid solution was sprayed onto said substrate; 
 a rotator which produces vortex in said acid solution in said container; and; 
 a particle collector which collects particles precipitating at an inner edge of said container; and 
   (d) a circulation system which circulates said acid solution having been sprayed onto said substrate, to said filter system, and further, to said nozzle system from said filter system.   
     
     
         2 . A method of fabricating a TFT array substrate, comprising:
 (A) adhering a protection film onto an upper surface of a glass substrate containing silicon dioxide as a principal constituent on which an etching stopper film having an etching rate five times or more slower than an etching rate of glass to hydrofluoric acid, and a thin film transistor array have been formed in this order; and   (B) etching said glass substrate through a lower surface thereof to entirely remove said glass substrate,   said step (B) comprising:   preparing an apparatus for etching a substrate; and   etching said glass substrate at an etching rate equal to or higher than 2 micrometers per a minute by means of said apparatus,   said apparatus comprising:   (a) a nozzle system including at least one nozzle through which acid solution containing at least hydrofluoric acid is sprayed onto said substrate;   (b) a mover which moves at least one of said nozzle system and said substrate relative to the other in a predetermined direction in such a condition that said substrate and said nozzle system face each other;   (c) a filter system which filters off particles out of said acid solution having been sprayed onto said substrate, said filter system including:
 a container which temporarily contains said acid solution before said acid solution is supplied to said nozzle mechanism after said acid solution was sprayed onto said substrate; 
 a rotator which produces vortex in said acid solution in said container; and; 
 a particle collector which collects particles precipitating at an inner edge of said container; and 
   (d) a circulation system which circulates said acid solution having been sprayed onto said substrate, to said filter system, and further, to said nozzle system from said filter system.   
     
     
         3 . The method as set forth in  claim 2 , wherein said etching stopper film contains at least one of gold, platinum, silver, copper, lead, tungsten, molybdenum, tantalum, chromium, oxide of these metals, fluoride of these metals, nitride of these metals, and chloride of these metals. 
     
     
         4 . A method of fabricating a device, comprising:
 (A) fabricating a device by adhering a pair of glass substrates to each other, each glass substrate containing silicon dioxide as a principal constituent, a thin film device having been fabricated on each of upper surfaces of said glass substrates, said glass substrates being adhered to each other such that said upper surfaces face each other; and   (B) etching said glass substrates through lower surfaces thereof,   said step (B) comprising:   preparing an apparatus for etching a substrate; and   etching said glass substrate at an etching rate equal to or higher than 2 micrometers per a minute by means of said apparatus,   said apparatus comprising:   (a) a nozzle system including at least one nozzle through which acid solution containing at least hydrofluoric acid is sprayed onto said substrate;   (b) a mover which moves at least one of said nozzle system and said substrate relative to the other in a predetermined direction in such a condition that said substrate and said nozzle system face each other;   (c) a filter system which filters off particles out of said acid solution having been sprayed onto said substrate, said filter system including:
 a container which temporarily contains said acid solution before said acid solution is supplied to said nozzle mechanism after said acid solution was sprayed onto said substrate; 
 a rotator which produces vortex in said acid solution in said container; and; 
 a particle collector which collects particles precipitating at an inner edge of said container; and 
   (d) a circulation system which circulates said acid solution having been sprayed onto said substrate, to said filter system, and further, to said nozzle system from said filter system.   
     
     
         5 . The method as set forth in  claim 4 , wherein a thin film transistor array is fabricated on one of said glass substrates, and a color filter is fabricated on the other.