US 7,592,242 B2
Apparatus and method for controlling diffusion
Paul A. Farrar, Okatie, S.C. (US); and Jerome M. Eldridge, Los Gatos, Calif. (US)
Assigned to Micron Technology, Inc., Boise, Id. (US)
Filed on Aug. 30, 2005, as Appl. No. 11/215,466.
Application 11/215466 is a division of application No. 10/326935, filed on Dec. 20, 2002.
Prior Publication US 2006/0003559 A1, Jan. 05, 2006
Int. Cl. H01L 21/33 (2006.01)
U.S. Cl. 438—514  [438/149; 438/301; 438/510; 257/E21.336; 257/E29.086] 26 Claims
OG exemplary drawing
 
1. A method of reducing a dopant diffusion rate in a doped semiconductor region comprising:
selecting a plurality of dopant elements, including:
selecting a first dopant element with a first atomic radius larger than a host matrix atomic radius;
selecting a second dopant element with a second atomic radius smaller than a host matrix atomic radius;
selecting amounts of each dopant element of the plurality of dopant elements wherein amounts and atomic radii of each of the plurality of dopant elements complement each other to substantially eliminate a host matrix lattice strain;
introducing the plurality of dopant elements together in a selected region of the host matrix;
annealing the selected region of the host matrix;
defining a maximum dopant element diffusion distance when the host matrix lattice strain is substantially eliminated, the maximum diffusion distance being shorter than a single impurity element diffusion distance; and
locating a semiconductor feature adjacent to the semiconductor region at a distance that is shorter than the single impurity element diffusion distance.