Method for measuring impurity concentration profile, wafer used for same, and method for manufacturing semiconductor device using same

Abstract

According to an embodiment, a method for measuring an impurity concentration profile uses a wafer including a semiconductor layer. The method includes measuring an impurity concentration profile in a depth direction from each surface of a plurality of first portions, each of the first portions being included in any one of a plurality of first regions provided in the semiconductor layer. Each of the first regions has a different size and is surrounded by a second region including a second portion having a different structure from the first portion. The method includes determining a change between the impurity concentration profiles measured in the first regions.

1 . A method for measuring an impurity concentration profile using a wafer including a semiconductor layer comprising:
 measuring an impurity concentration profile in a depth direction from each surface of a plurality of first portions, each of the first portions being included in any one of a plurality of first regions provided in the semiconductor layer, each of the first regions having a different size and being surrounded by a second region including a second portion having a different structure from the first portion; and   determining a change between the impurity concentration profiles measured in the first regions.   
     
     
         2 . The method according to  claim 1 , wherein the impurity concentration profile is measured using a secondary ion mass spectroscopy method. 
     
     
         3 . The method according to  claim 2 , wherein the first portion is larger than an irradiation area of an ion beam used for the secondary ion mass spectroscopy method. 
     
     
         4 . The method according to  claim 1 , wherein the wafer is fabricated for monitoring the impurity concentration profile, wherein the semiconductor layers are simultaneously formed on both a substrate for monitoring the impurity concentration profile and a substrate for manufacturing a semiconductor device. 
     
     
         5 . The method according to  claim 1 , wherein a change between peak concentrations is determined in the impurity concentration profiles measured in the first regions. 
     
     
         6 . The method according to  claim 5 , wherein the change between the peak concentrations is used for estimating a peak concentration of the impurity profile in a desired area. 
     
     
         7 . The method according to  claim 1 , wherein a change between impurity concentration gradients is determined in the impurity concentration profile measured in the first regions. 
     
     
         8 . A wafer comprising:
 a substrate; and   a semiconductor layer provided on the substrate and including a plurality of first portions, each of the first portions being formed in any one of a plurality of first regions having a different area from each other, each of the first regions being surrounded by a second region including a second portion having a different structure from the first portion.   
     
     
         9 . The wafer according to  claim 8 , wherein at least three of the first regions with different sizes are provided in the semiconductor layer. 
     
     
         10 . The wafer according to  claim 8 , wherein the substrate includes an element region and a plurality of TEG regions and each of the first regions is included in the TEG region. 
     
     
         11 . The wafer according to  claim 8 , wherein the first portion includes a single crystal and the second portion includes a polycrystal. 
     
     
         12 . The wafer according to  claim 8 , wherein the semiconductor layer contains silicon and germanium. 
     
     
         13 . A method for manufacturing a semiconductor device using a wafer including a semiconductor layer comprising:
 measuring an impurity concentration profile in a depth direction from each surface of a plurality of first portions, each of the first portions being included in any one of a plurality of first regions provided in the semiconductor layer, each of the first regions having a different size and being surrounded by a second region including a second portion having a different structure from the first portion; and   determining a growth condition for the semiconductor layer based on a change between the impurity concentration profiles measured in the first regions.   
     
     
         14 . The method according to  claim 13 , wherein a growth condition for the semiconductor layer is determined based on a prescribed change of the impurity concentration profile. 
     
     
         15 . The method according to  claim 13 , wherein the growth condition for the semiconductor layer is determined based on the impurity concentration profiles measured after a wafer test after an epitaxial growth. 
     
     
         16 . The method according to  claim 15 , wherein a control range is set for an impurity concentration of the semiconductor layer and the change of the impurity concentration profile is measured, when the impurity concentration of the semiconductor layer deviates from the control range. 
     
     
         17 . The method according to  claim 13 , wherein the growth condition of the semiconductor layer is determined based on the change of the impurity concentration profile measured after a characteristic test of the semiconductor layer carried out after wafer process. 
     
     
         18 . The method according to  claim 17 , wherein a control range is set for a resistance of the semiconductor layer and the change of the impurity concentration profile is measured, when the resistance of the semiconductor layer deviates from the control range. 
     
     
         19 . The method according to  claim 13 , wherein the growth condition for the semiconductor layer is determined based on the change of the impurity concentration profile measured after a characteristic test of a semiconductor device. 
     
     
         20 . The method according to  claim 19 , wherein a control range is set for a frequency response of the semiconductor device and the change of the impurity concentration profile is measured, when the frequency response deviates from the control range.