III-nitride parameters

Wurtzite polytype:

GaN

AlN

InN

Bandgap energy (eV)

3.44 (300 K)

6.20 (300K)

0.62- 0.7 eV (300K)

Lattice Constant 

(Å)

a = 3.189

c = 5.185

a = 3.112

c = 4.982

a = 3.548

c=5.760

Thermal expansion 
(x10-6/K)

da/a = 5.59
dc/c=3.17

da/a = 4.2
dc/c = 5.3

da/a = 4.0
dc/c = 3.0

Thermal conductivity k (W/cm K )

1.3

2.0

0.8

Index of refraction

n(1 eV)=2.33
n(3.38 eV)=2.67

n(3 eV)=2.15

n=2.9-3.05

Dielectric constants

er =9

e¥ =5.35 

er =8.5

e¥=4.68-4.84

er =15, estimated

e¥ =8.4 

me *

0.23

0.33

0.11

mh *

0.8

2.7

0.5

Zinc-blende structure:

GaN

AlN

InN

Bandgap energy (eV)
(300 K)

3.2-3.3

5.11 (theory)

2.2 (theory)

Lattice constant a 
(Å )

4.52

4.38

4.98

 

Band-gap Lattice constantStructure