Method of making an epitaxial wafer

Abstract

There are provided silicon single crystal, silicon wafer, and epitaxial wafer having a sufficient gettering effect suitable for a large-scale integrated device. The silicon single crystal which is suitable for an epitaxial wafer is grown with nitrogen doping at a concentration of 1×10 13 atoms/cm 3 or more, or with nitrogen doping at a concentration of 1×10 12 atoms/cm 3 and carbon doping at a concentration of 0.1×10 16 -5×10 16 atoms/cm 3 and/or boron doping at a concentration of 1×10 17 atoms/cm 3 or more. The silicon wafer is produced by slicing from the silicon single crystal, and an epitaxial layer is grown on a surface of the silicon wafer to produce the epitaxial wafer. The present invention provides an epitaxial wafer for a large-scale integrated device having no defects in a device-active region and having an excellent gettering effect without performance of an extrinsic or intrinsic gettering treatment, which is a factor for increasing the number of production steps and production costs.

1 .- 20 . (cancelled)  
     
     
         21 . A method of making an epitaxial wafer, which is produced without extrinsic gettering treatment, comprising the steps of: 
 a) growing a silicon single crystal with a nitrogen doping concentration of 1×10 13  atoms/cm 3  or more;    b) slicing the grown silicon singe crystal into wafers;    c) selecting one of the wafers and subjecting it to a thermal oxidation treatment;    d) measuring a density of oxidation-induced stacking faults generated in the wafer due to the thermal oxidation treatment; and    e) growing an epitaxial layer on the wafers if the density of oxidation-induced stacking faults in the selected wafer is 1×10 2 /cm 2  or more.    
     
     
         22 . A method of making an epitaxial wafer, which is produced without extrinsic gettering treatment, comprising the steps of: 
 a) growing a silicon single crystal with a nitrogen doping concentration of 1×10 13  atoms/cm 3  or more;    b) slicing the grown silicon singe crystal into wafers;    c) selecting one of the wafers and subjecting it to a thermal treatment of 1100° C. or more;    d) measuring a density of defects generated in the wafer due to the thermal treatment; and    e) growing an epitaxial layer on the wafers if the density of defects in the selected wafer is 5×10 3 /cm 2  or more.    
     
     
         23 . A method of making an epitaxial wafer, which is produced without extrinsic gettering treatment, comprising the steps of: 
 a) growing a silicon single crystal and controlling a nitrogen doping of the single crystal such that the nitrogen doping concentration is 1×10 13  atoms/cm 3  or more;    b) slicing the grown silicon singe crystal into wafers; and    c) growing an epitaxial layer on each of the wafers.