Novel method for conformal plasma immersed ion implantation assisted by atomic layer deposition

Abstract

Embodiments of the invention provide a novel apparatus and methods for forming a conformal doped layer on the surface of a substrate. A substrate is provided to a process chamber, and a layer of dopant source material is deposited by plasma deposition, atomic layer deposition, or plasma-assisted atomic layer deposition. The substrate is then subjected to thermal processing to activate and diffuse dopants into the substrate surface.

1 - 8 . (canceled) 
   
   
       9 . A method of processing a substrate, comprising:
 disposing the substrate in a process chamber;   providing a process gas mixture to the process chamber, wherein the process gas mixture comprises a dopant precursor;   ionizing the dopant precursor into a plasma comprising dopant ions inside the process chamber;   generating a weak electrical bias; and   depositing the dopant ions conformally on the substrate.   
   
   
       10 . The method of  claim 9 , wherein the dopant precursor comprises a boron compound, a phosphorus compound, an arsenic compound, a metal compound, a fluorine compound, or a mixture thereof. 
   
   
       11 . The method of  claim 9 , further comprising annealing the substrate. 
   
   
       12 . The method of  claim 9  wherein the weak electrical bias is generated by applying an electrical bias to a gas distributor. 
   
   
       13 . The method of  claim 12  wherein the electrical bias is applied to the gas distributor by coupling RF power to the gas distributor. 
   
   
       14 . The method of  claim 13  wherein the RF power is less than about 100 watts. 
   
   
       15 . The method of  claim 9 , wherein the plasma is generated by applying power less than about 1000 W to an inductively coupled plasma source. 
   
   
       16 . The method of  claim 9 , wherein the process gas mixture further comprises a purge gas. 
   
   
       17 . The method of  claim 11 , wherein annealing the substrate comprises heating one or more portions of the substrate to a temperature between about 700° C. and about 1410° C. 
   
   
       18 - 20 . (canceled) 
   
   
       21 . A method of implanting dopants into a substrate in a processing chamber, comprising:
 positioning the substrate having high aspect ratio features on a substrate support in the processing chamber;   forming a dopant precursor plasma comprising ions in the processing chamber by inductively coupling RF power into a dopant precursor;   attracting the ions from the dopant precursor plasma to the substrate by applying an electrical bias at a power level less than about 500 W;   depositing the dopant ions conformally on a surface of the substrate; and annealing the substrate.   
   
   
       22 . The method of  claim 21 , wherein the dopant precursor comprises a boron compound, a phosphorus compound, an arsenic compound, a metal compound, a fluorine compound, or a mixture thereof. 
   
   
       23 . The method of  claim 22 , wherein the dopant precursor further comprises a purge gas. 
   
   
       24 . The method of  claim 21 , wherein the RF power is coupled into the dopant precursor at a power level less than about 1000 W. 
   
   
       25 . The method of  claim 24 , wherein annealing the substrate comprises selectively melting portions of the substrate surface. 
   
   
       26 . The method of  claim 21 , wherein the electrical bias is an RF bias. 
   
   
       27 . The method of  claim 26 , wherein depositing the dopant ions conformally on a surface of the substrate comprises propelling ions into the high aspect ratio features of the surface before they deposit on the surface. 
   
   
       28 . The method of  claim 21 , wherein annealing the substrate comprises heating the substrate to a temperature between about 700° C. and about 1,410° C. in the processing chamber. 
   
   
       29 . The method of  claim 28 , wherein the dopant precursor comprises a purge gas and a component selected from the group consisting of a boron compound, a phosphorus compound, an arsenic compound, a metal compound, a fluorine compound, and combinations thereof. 
   
   
       30 . A method of processing a substrate having high aspect ratio features formed therein, comprising:
 disposing the substrate on a substrate support in a processing chamber;   providing a gas mixture to the processing chamber through a gas distributor disposed above the substrate support in the processing chamber, the gas mixture comprising a purge gas and a dopant component selected from the group consisting of a boron compound, a phosphorus compound, an arsenic compound, a metal compound, a fluorine compound, and combinations thereof;   ionizing the gas mixture to form a plasma by inductively coupling RF power into the gas mixture at a power level less than about 1,000 W;   attracting ions from the plasma toward the substrate by applying a weak electrical bias;   depositing dopants from the plasma conformally over the substrate surface;   annealing the substrate in the processing chamber by heating the substrate surface to a temperature between about 700° C. and about 1,410° C.; and   removing dopants from the substrate surface.   
   
   
       31 . The method of  claim 30 , wherein the weak electrical bias is a DC bias applied at a power level less than about 500 W.