Mobility measuring apparatus, method therefor, and resistivity measuring apparatus and method therefor

A mobility measuring method for measuring a mobility μ of carriers in a semiconductor, comprising:

• obtaining a relationship between the mobility μ of the carriers and a decay constant γ of the carriers, a relationship between said decay constant γ and a carrier density N of said semiconductor and a relationship between a reflectivity R of said semiconductor to a terahertz light and said carrier density N, wherein said decay constant γ changes linearly relative to said carrier density N in said relationship between said decay constant γ and a carrier density N;
• radiating a terahertz light to said semiconductor as a sample;
• detecting a reflected light of said semiconductor to said radiated terahertz light;
• calculating a reflectivity Rexp of said sample by determining a ratio of an intensity of said reflected light relative to an intensity of said radiated terahertz light;
• obtaining a carrier density Nexp of said sample corresponding to the reflectivity Rexp of said sample by making reference to said stored relationship between said reflectivity R and said carrier density N and obtaining a decay constant γexp of said sample corresponding to said obtained carrier density Nexp by making reference to said stored relationship between said carrier density N and said decay constant γ, wherein said decay constant γexp is calculated b detecting said decay constant γ that corresponds to said obtained carrier density Nexp in said relationshi between said decay constant γ and a carrier density Nexp, wherein said relationship between said decay constant γ and a carrier density N is obtained by fitting a plurality of plots of a relationship between said decay constant γ and said carrier density N;
• and
• calculating said mobility μexp of said sample from said stored relationship between said mobility μ and said decay constant γexp on the basis of said obtained decay constant γexp.

An electric resistivity measuring apparatus for measuring an electric resistivity ρ of a semiconductor, comprising:

• a storage unit that respectively stores a relationship between said electric resistivity ρ, a decay constant γ of carriers in said semiconductor, and a carrier density N, a relationship between a reflectivity R of said semiconductor to a terahertz light and said carrier density N, and a relationship between said carrier density N and said decay constant γ, wherein said decay constant v changes linearly relative to said carrier density N in said relationship between said decay constant γ and a carrier density N;
• a light radiating unit that radiates a terahertz light to said semiconductor as a sample;
• a detecting unit that detects a reflected light of said sample to said radiated terahertz light;
• a reflectivity calculating unit that calculates a reflectivity Rexp of said sample by determining a ratio of an intensity of said reflected light relative to an intensity of said radiated terahertz light;
• an obtaining unit that obtains a carrier density Nexp of said sample corresponding to the reflectivity Rexp of said sample by making reference to said stored relationship between said reflectivity R and said carrier density N and obtains a decay constant γexp of said sample corresponding to said obtained carrier density Nexp by making reference to said stored relationship between said carrier density N and said decay constant γ, wherein said decay constant γexp is calculated by detecting said decay constant γ that corresponds to said obtained carrier density Nexp in said relationship between said decay constant γ and a carrier density N, wherein said relationship between said decay constant γ and a carrier density N is obtained by fitting a plurality of plots of a relationship between said decay constant γ and said carrier density N;
• and
• a resistivity calculating unit that calculates said electric resistivity ρexp of said sample from said stored relationship between said electric resistivity ρ, said decay constant γ, and said carrier density N on the basis of said obtained carrier density Nexp and said obtained decay constant γexp.

An electric resistivity measuring method for measuring an electric resistivity ρ of a semiconductor, comprising:

• respectively obtaining a relationship between said electric resistivity ρ, a decay constant γ of carriers in said semiconductor, and a carrier density N, a relationship between a reflectivity R of said semiconductor to a terahertz light and said carrier density N, and a relationship between said carrier density N and said decay constant γ, wherein said decay constant v changes linearly relative to said carrier density N in said relationship between said decay constant v and a carrier density N;
• radiating a terahertz light to said semiconductor constituting a sample;
• detecting a reflected light of said sample to said radiated terahertz light;
• calculating a reflectivity Rexp of said sample by determining a ratio of an intensity of said reflected light relative to an intensity of said radiated terahertz light;
• obtaining a carrier density Nexp of said sample corresponding to the reflectivity Rexp of said sample by making reference to said stored relationship between said reflectivity R and said carrier density N and obtaining a decay constant γexp of said sample corresponding to said obtained carrier density Nexp by making reference to said stored relationship between said carrier density N and said decay constant γ, wherein said decay constant γexp is calculated b detecting said decay constant γ that corresponds to said obtained carrier density Nexp, in said relationship between said decay constant γ and a carrier density N, wherein said relationship between said decay constant γ and a carrier density N is obtained by fitting a plurality of plots of a relationship between said decay constant γ and said carrier density N;
• and
• calculating said electric resistivity ρexp of said sample from said stored relationship between said electric resistivity ρ, said decay constant γ, and said carrier density N on the basis of said obtained carrier density Nexp and said obtained decay constant γexp.