Band structure and carrier concentration of Gallium Antimonide (GaSb)
Band structure and carrier concentration
Basic ParametersTemperature Dependences
Dependence of the Energy Gap on Hydrostatic Pressure
Energy Gap Narrowing at High Doping Levels
Effective Masses
Donors and Acceptors
Basic Parameters
Energy gap  0.726 eV 
Energy separation (E_{ΓL}) between Γ and L valleys  0.084 eV 
Energy separation (E_{ΓX}) between Γ and X valleys  0.31 eV 
Energy spinorbital splitting  0.80 eV 
Intrinsic carrier concentration  1.5·10^{12} cm^{3} 
Intrinsic resistivity  10^{3} Ω·cm 
Effective conduction band density of states  2.1·10^{17} cm^{3} 
Effective valence band density of states  1.8·10^{19} cm^{3} 
Band structure and carrier concentration of GaSb. 300 K E_{g}= 0.726 eV E_{L} = 0.81 eV E_{X} = 1.03 eV E_{so} = 0.8 eV 
Temperature Dependences
Temperature dependence of the energy gap
(Wu and Chen [1992])
E_{g} = 0.813  3.78·10^{4}·T^{2}/(T+94) (eV),where T is temperature in degrees K (0 < T < 300).
Temperature dependence of energy E_{L}
E_{L} = 0.902  3.97·10^{4}·T^{2}/(T+94) (eV)Temperature dependence of energy E_{X}
(Lee and Woolley [1981])
E_{X} = 1.142  4.75·10^{4}·T^{2}/(T+94) (eV)
Effective density of states in the conduction band
N_{c} = 4.0·10^{13}·T^{3/2} (cm^{3})Effective density of states in the conduction band
N_{c} = 4.0·10^{13}·T^{3/2} (cm^{3})Effective density of states in the valence band
N_{v} = 3.5·10^{15}·T^{3/2} (cm^{3})The temperature dependences of the intrinsic carrier concentration. 
Dependences on Hydrostatic Pressure
E_{g} = E_{g}(0) + 14.5·10^{3}P (eV)E_{L} = E_{L}(0) + 5.0·10^{3}P (eV)
E_{X} = E_{X}(0)  1.5·10^{3}P (eV),
where P is pressure in kbar.
Energy Gap Narrowing at High Doping Levels
Energy gap narrowing versus acceptor acceptor doping density. Curve is calculated for pGaSb according to Jain et al. [1990]. Points show experimental results (Titkov et al. [1981]). 
For ntype GaSb
(Jain et al. [1990]):
E_{g} = 13.6·10^{9}·N_{d}^{1/3} +
1.66·10^{7}·N_{d}^{1/4} +
119·10^{12}·N_{d}^{1/2} (eV)
For ptype GaSb
(Jain et al. [1990]):
E_{g} = 8.07·10^{9}·N_{a}^{1/3} +
2.80·10^{7}·N_{a}^{1/4}+
4.12·10^{12}·N_{a}^{1/2} (eV)
Effective Masses
Electrons:
For Γvalley  m_{Γ} = 0.041m_{o} 
In the L valley the surfaces of equal energy are ellipsoids  
m_{l}= 0.95m_{o}  
m_{t}= 0.11m_{o}  


m_{L}= 16(m_{l}m_{t}^{2})^{1/3}= 0.57m_{o}  
In the X valley the surfaces of equal energy are ellipsoids  
m_{l}= 1.51m_{o}  
m_{t}= 0.22m_{o}  


m_{X}= 9(m_{l}m_{t}^{2})^{1/3}= 0.87m_{o} 
Holes:
Heavy 
m_{h} = 0.4m_{o} 
Light 
m_{lp} = 0.05m_{o} 

m_{so} = 0.14m_{o} 
Effective mass of density of states  m_{v} = 0.8m_{o} 
Effective mass of density of conductivity (Heller and Hamerly [1985]) 
m_{vc} = 0.3m_{o} 
Donors and Acceptors
The diagram of IV group donor states (Vul' et al. [1970]). 
Ionization energies of shallow donors (eV)
Te(L)  Te(X)  Se(L)  Se(X)  S(L)  S(X) 
~0.02  ≤0.08  ~0.05  ~0.23  ~0.15  ~0.30 
Ionization energies of shallow acceptors (eV):
The dominant acceptor of undoped GaSb seems to be a native defect.This acceptor is doubly ionizable
E_{a1}  E_{a2}  Si  Ge  Zn 
0.03  0.1  ~0.01  ~0.009  ~0.037 