Sputtering apparatus for depositing a higher permittivity dielectric film

Abstract

A method of depositing a high permittivity dielectric film on a doped silicon or silicon compound layer of a wafer. The method includes a first step of nitriding a specific element (A) such as hafnium Hf to form a nitride film (A x N y ) on the silicon layer, wherein the specific element (A) and nitrogen (N) in the nitride film (A x N y ) have a predetermined fraction relationship between x and y; a second step of oxidizing the nitride film in a oxygen atmosphere to form the dielectric film (AON).

1 . A reactive sputtering apparatus comprising:
 a process chamber,   a wafer holder for holding a wafer rotatably in the process chamber,   a cathode with a target containing a metal element, wherein the target is supplied with an electric power used for generating plasma, and is placed so as to be inclined to an upper surface of the wafer holder at a position of being above the wafer holder and dislocated from a rotation axis of the wafer holder,   a gas inlet for introducing a nitrogen gas upward in the process chamber, which is positioned to be dislocated from the rotation axis of the wafer holder and below the wafer held by the wafer holder at an opposite side to the cathode across the rotation axis, and   a vacuuming port positioned to be below the wafer holder at an opposite side to the gas inlet across the rotation axis.   
   
   
       2 . A reactive sputtering apparatus according to  claim 1 ,
 wherein the metal element is Hafnium metal, and the nitrogen gas is introduced through the gas inlet at a predetermined flow rate so that resistivity of nitride Hafnium (HfN) film formed on the wafer by reactive sputtering is not more than 1.0×10 5  μΩcm.   
   
   
       3 . A reactive sputtering apparatus according to  claim 2 ,
 wherein the predetermined flow rate is not less than 5 sccm and not more than 15 sccm.