Etching method and etching apparatus

Abstract

An etching method which uses an apparatus having a chamber in which an etching gas is excited by plasma; a table arranged in the chamber which heats a substrate mounted thereon; and a frame member which includes etching-endurable material which is arranged around the table, and which has an upper surface arranged at a position lower than an upper surface of the table, the etching method including: arranging the substrate on the upper surface of the table such that a peripheral part of the substrate projects above the table; and arranging the substrate such that a ratio of a height from the upper surface of the frame member to a bottom surface of the substrate and a projecting length from a side surface of the table to an outer circumference of the substrate is 1.5 or more

1 . An etching method which uses an apparatus having:
 a chamber in which an etching gas is excited by a plasma;   a table arranged in the chamber which heats a subject substrate mounted thereon; and   a frame member which includes an etching-endurable material arranged around the table, and which has an upper surface arranged at a position lower than an upper surface of the table, the etching method comprising:
 arranging the subject substrate on the upper surface of the table such that a peripheral part of the subject substrate projects above the table; and 
 arranging the subject substrate such that a ratio H/G of a height from the upper surface of the frame member to a bottom surface of the subject substrate and a projecting length from a side surface of the table to an outer circumference of the subject substrate is 1.5 or more. 
   
   
   
       2 . The etching method according to  claim 1 , wherein the table includes a material having aluminum nitride as a major component. 
   
   
       3 . The etching method according to  claim 1 , further comprising:
 arranging the subject substrate such that the height from the upper surface of the frame member to the bottom surface of the subject substrate becomes  1 . 0 mm or more.   
   
   
       4 . The etching method according to  claim 1 , further comprising:
 etching a noble metal coating and a ferroelectric film formed on the subject substrate by the etching gas.   
   
   
       5 . The etching method according to  claim 4 , wherein the noble metal coating and the ferroelectric film configure a storage device of a ferroelectric memory. 
   
   
       6 . The etching method according to  claim 4 , wherein the noble metal coating includes at least one of Pt (platinum), Ir (iridium), IrO 2  (iridium oxide), and SrRuO 3  (strontium ruthenium oxide). 
   
   
       7 . The etching method according to  claim 4 , wherein the ferroelectric film includes at least one of PZT (Pb(Zr,Ti)O 3 , lead zirconate titanate), SBT (SrBi 2 Ta 2 O 9 ; strontium bismuth tantalate), BTO (Bi 4 Ti 3 O 12 ; bismuth titanate), and BLT ((Bi,La) 4 Ti 3 O 12 ; bismuth lanthanum titanate). 
   
   
       8 . An etching apparatus comprising:
 a chamber in which an etching gas is excited by plasma;   a table arranged in the chamber, the table heating a subject substrate which is mounted on the table; and   a frame member arranged around the table which includes etching-endurable material, wherein:
 the frame member has an upper surface which is arranged at a position lower than an upper surface of the table; and 
 an external form of the table is configured such that, above the frame member, a peripheral part of the subject substrate arranged on the upper surface of the table projects, and is configured such that a ratio H/G of a height G from the upper surface of the frame member to a bottom surface of the subject substrate and a projecting length H from a side surface of the table to an outer circumference of the subject substrate is 1.5 or more.