Method for forming thin film

Abstract

The present invention relates to a method for forming a thin film, and more particularly, to a method for forming a thin film comprising steps of:i) absorbing a growth inhibitor for forming a thin film on a surface of a substrate, the growth inhibitor for forming a thin film being represented by Chemical Formula 1 below; and ii) adsorbing a Ti-based thin film precursor on a surface of a substrate on which the growth inhibitor is adsorbed.AnBmXo  [Chemical Formula 1]wherein A is carbon or silicon, B is hydrogen or a C1-C3 alkyl, X is a halogen, n is an integer of 1 to 15, o is an integer of 1 or more, and m is 0 to 2n+1.According to the present invention, it is possible to suppress side reactions to appropriately lower a thin film growth rate and remove process byproducts in the thin film, thereby preventing corrosion or deterioration and greatly improving step coverage and thickness uniformity of a thin film, even when the thin film is formed on a substrate having a complex structure.

What is claimed is: 
     
         1 . A method for forming a thin film comprising steps of:
 i) adsorbing a growth inhibitor for forming a thin film on a surface of a substrate, the growth inhibitor for forming a thin film being represented by Chemical Formula 1 below; and   ii) adsorbing a Ti-based thin film precursor on a surface of a substrate on which the growth inhibitor is adsorbed.
   AnBmXo  [Chemical Formula 1]
 
   wherein A is carbon or silicon, B is hydrogen or a C1-C3 alkyl, X is a halogen, n is an integer of 1 to 15, o is an integer of 1 or more, and m is 0 to 2n+1.   
     
     
         2 . The method for forming a thin film of  claim 1 , wherein in the step of i) adsorbing the growth inhibitor for forming a thin film on the surface of the substrate, the feeding time for the growth inhibitor is 1 to 10 seconds. 
     
     
         3 . The method for forming a thin film of  claim 1 , wherein the step of i) adsorbing the growth inhibitor for forming a thin film on the surface of the substrate comprises a step of injecting the growth inhibitor for forming a thin film into an atomic layer deposition (ALD) chamber and adsorbing the growth inhibitor onto a surface of a loaded substrate. 
     
     
         4 . The method for forming a thin film of  claim 1 , wherein the step of i) adsorbing the growth inhibitor for forming a thin film on the surface of the substrate comprises a step of purging the remaining inhibitor unadsorbed on the surface of the substrate for forming the thin film with a purge gas. 
     
     
         5 . The method for forming a thin film of  claim 1 , wherein the step of ii) adsorbing a Ti-based thin film precursor may preferable comprise a step of purging the remaining unadsorbed Ti-based thin film precursor with a purge gas. 
     
     
         6 . The method for forming a thin film of  claim 1 , further comprising steps of supplying a reaction gas after adsorption of a Ti-based thin film precursor on the surface of the substrate, and purging reaction byproducts of the Ti-based thin film precursor and the reaction gas with a purge gas. 
     
     
         7 . The method for forming a thin film of  claim 6 , wherein the reaction gas comprises a reducing agent, a nitriding agent, or an oxidizing agent 
     
     
         8 . The method for forming a thin film of  claim 1 , wherein the growth inhibitor for forming a thin film and the Ti-based thin film precursor are transferred into the ALD chamber by a vapor flow control (VFC) method, a delivery liquid injection (DLI) method, or a liquid delivery system (LDS) method. 
     
     
         9 . The method for forming a thin film of  claim 1 , wherein the ratio of the feeding amount (mg/cycle) between the growth inhibitor for forming a thin film and the Ti-based precursor in the ALD chamber is from 1:1.5 to 1: 20. 
     
     
         10 . The method for forming a thin film of  claim 1 , wherein X is chlorine (Cl). 
     
     
         11 . The method for forming a thin film of  claim 1 , wherein o is an integer from 1 to 5. 
     
     
         12 . The method for forming a thin film of  claim 1 , wherein the compound represented by Chemical Formula 1 is a branched, cyclic or aromatic compound. 
     
     
         13 . The method for forming a thin film of  claim 1 , wherein the compound represented by Chemical Formula 1 is a liquid at room temperature (22° C.), and has a density of 0.8 to 1.5 g/cm 3 , a vapor pressure (20° C.) of 1 to 300 mmHg, and solubility in water (25° C.) of 200 mg/L or less. 
     
     
         14 . The method for forming a thin film of  claim 1 , wherein a reduction rate of a thin film growth rate (Å/cycle) per cycle calculated by the following Equation 1 is -5% or less.
   Reduction rate of thin film growth rate per cycle (%)=[(thin film growth rate per cycle when growth inhibitor for forming thin film is used—thin film growth rate per cycle when growth inhibitor for forming thin film is not used)/thin film growth rate per cycle when growth inhibitor for forming thin film is not used]×100  [Equation 1]
 
 
     
     
         15 . The method for forming a thin film of  claim 1 , wherein the residual halogen intensity (c/s) of the thin film formed after 200 cycles, which is measured based on SIMS, is 10,000 or less. 
     
     
         16 . An apparatus for preparing a thin film comprising:
 an atomic layer deposition (ALD) chamber,   a first vaporizer for vaporizing the growth inhibitor for forming a thin film,   a first transfer unit for transferring the vaporized growth inhibitor into the ALD chamber,   a second vaporizer for vaporizing a Ti-based thin film precursor, and   a second transfer unit for transferring the vaporized Ti-based thin film precursor into the ALD chamber.