NSM Archive  Diamond (C)  Band structure and carrier concentration
Band structure and carrier concentration
Basic ParametersTemperature Dependences
Effective Masses and Density of States
Donors and Acceptors
Basic Parameters
Energy gap  5.465.6 eV 
Energy separation (E_{Γ1})  7.37.4 eV 
Energy of spinorbital splitting E_{s0}  0.006 eV 
Intrinsic carrier concentration  ~10^{27} cm^{3} 
Intrinsic resistivity  ≥10^{42}Ω·cm 
Resistivity of diamonds types I and IIa (usually)  ~10^{16}Ω·cm 
Resistivity of diamonds type IIb  ~110^{3}Ω·cm 
Effective conduction band density of states  ~10^{20} cm^{3} 
Effective valence band density of states  ~10^{19} cm^{3} 
Band structure and carrier concentration of Diamond. 300 K

Temperature Dependences
Temperature dependence of the energy gap (Clark et al., 1964) 
dE_{g}/dT=(5.4±0.5)·10^{5} eV K^{1} (Vavilov and Konorova [1976]).
dE_{Γ1}/dT=6·10^{4} eV K^{1} (Clark et al. [1964]).
Effective Masses and Density of States
Electrons
The surfaces of equal energy are ellipsoids.
m_{l}=1.4m_{o}
m_{t}=0.36m_{o}
Effective mass of density of states in one valley of conduction band
m_{c}=(m_{l}·m_{t}^{2})^{1/3}=0.57m_{o}
There are 6 equivalent valleys in the "Silike" conduction band of diamond.
Effective mass of density of states for all valleys of conduction band m_{cd}≈
1.9m_{o}
Effective mass of conductivity m_{cc}=3(1/m_{l}+ 2/m_{t})^{1}=0.48m_{o}
Holes
Cyclotron resonance measurement date (Rauch [1962]):
heavy  m_{h}= 2.12m_{o} 
light  m_{lp}= 0.7m_{o} 
splitoff band  m_{so}=1.06m_{o} 
Effective mass of density of states m_{ν}=0.8m_{o}
There is a considerable uncertainty regarding the density of states effective mass. There is a considerable uncertainty regarding the density of states effective mass. The values as low as m_{ν}=0.16m_{o} (Kemmey and Wederpohl [1965]) and as high as m_{ν}=1.1m_{o} (Dean [1965]) have been reported. For estimations, one can use the value of m_{ν}=0.8m_{o}which is close to m_{ν}=0.75m_{o} (Collins and Williams [1971]) and m_{ν}=0.88m_{o} (Prosser [1964]).
Donors and Acceptors
B (boron):
Boron is a deep acceptor level with activation energy of 0.37 eV. So far semiconductor applications of diamond have been based almost exclusively on borondoped ptype samples (Gildenblat et al. [1991]).
N (nitrogen):
Nitrogen is a most common impurity (donor) in diamond. It is difficult to specify the activation energy since nitrogen can appear as isolated substitutional impurity, simple aggregates or platelets (Stoneham [1992]). In particular, the energy levels of 1.7 eV and 4 eV below the bottom of the conduction band are often ascribed to nitrogen impurities (Davies [1977]; Vermeulen and Farer [1975]; Novikov [1987]).