Semiconductor device and method for manufacturing the same

Abstract

It is made possible to provide a semiconductor device and a method for manufacturing the semiconductor device that have the highest possible permittivity and can be produced at low production costs. A method for manufacturing a semiconductor device, includes: forming an amorphous film containing (Hf z Zr 1−z ) x Si 1−x O 2−y (0.81≦x≦0.99, 0.04≦y≦0.25, 0≦z≦1) on a semiconductor substrate, the ranges of composition ratios x, y, and z being values measured by XPS; and transforming the amorphous film into an insulating film containing (Hf z Zr 1−z ) x Si 1−x O 2 as tetragonal crystals, by performing annealing at 750° C. or higher on the amorphous film in an atmosphere containing oxygen.

1 . A method for manufacturing a semiconductor device, comprising:
 forming an amorphous film containing (Hf z Zr 1−z ) x Si 1−x O 2−y  (0.81≦x≦0.99, 0.04≦y≦0.25, 0≦z≦1) on a semiconductor substrate, the ranges of composition ratios x, y, and z being values measured by XPS; and   transforming the amorphous film into an insulating film containing (Hf z Zr 1−z ) x Si 1−x O 2  as tetragonal crystals, by performing annealing at 750° C. or higher on the amorphous film in an atmosphere containing oxygen.   
     
     
         2 . The method according to  claim 1 , wherein a pressure in the atmosphere in which the annealing is performed is atmospheric pressure. 
     
     
         3 . The method according to  claim 1 , wherein oxygen content in the atmosphere containing oxygen is 1 ppm or higher. 
     
     
         4 . The method according to  claim 1 , wherein oxygen content in the atmosphere containing oxygen is 1% or higher. 
     
     
         5 - 22 . (canceled) 
     
     
         23 . The method according to  claim 1 , wherein molecular volume V m  of tetragonal crystals in the insulating film is in the range of
 0.03353 nm 3 ≦V m ≦0.03424 nm 3 , and the insulating film has a physical film thickness of 110 nm or smaller.   
     
     
         24 . The method according to  claim 1 , wherein lattice constants a, b, and c of tetragonal unit cells in the insulating film are in the ranges of
 0.3590 nm≦a≦0.3608 nm, 0.3590 nm≦b≦0.3608 nm, and 0.5183 nm≦c≦0.5212 nm, respectively.   
     
     
         25 . The method according to  claim 1 , wherein the insulating film has relative permittivity ranging from 20 to 26; and molar polarizability α of atoms constituting the insulating film is in the range of 0.00679 nm 3 <α≦0.00735 nm 3 . 
     
     
         26 . The method according to  claim 1 , wherein a′ axis of the tetragonal crystals in the semiconductor film extends substantially parallel to a film thickness direction of the insulating film. 
     
     
         27 . The method according to  claim 1 , wherein the stress applied onto the insulating film is 1 GPa or smaller. 
     
     
         28 . The method according to  claim 1 , wherein the insulating film is a gate insulating film of a CMOSFET. 
     
     
         29 . The method according to  claim 1 , wherein the insulating film is an interelectrode insulating film of a floating gate type flash memory. 
     
     
         30 . The method according to  claim 1 , wherein the insulating film is a blocking insulating film of a MONOS type flash memory.