Properties of RF Semiconductors

A semiconductor is a material that has electrical conductivity between those of a conductor and an insulator. The conductivity of a semiconductor material can be varied under an external electrical field. Devices made from semiconductor materials are the foundation of modern electronics, including radio, computers, telephones, and many other devices. Semiconductor devices include the transistor, many kinds of diodes including the light-emitting diode, the silicon controlled rectifier, and digital and analog integrated circuits. Solar photovoltaic panels are large semiconductor devices that directly convert light energy into electrical energy.

In a metallic conductor, current is carried by the flow of electrons. In semiconductors, current can be carried either by the flow of electrons or by the flow of positively-charged "holes" in the electron structure of the material. Silicon is used to create most semiconductors commercially. Dozens of other materials are used, including germanium, gallium arsenide, and silicon carbide. A pure semiconductor is often called an “intrinsic” semiconductor. The conductivity, or ability to conduct, of semiconductor material can be drastically changed by adding other elements, called “impurities” to the melted intrinsic material and then allowing the melt to solidify into a new and different crystal. This process is called "doping". - Wikipedia

Semiconductor Eg

(eV)

ni

(cm-3)

εr μn

(cm2/V∙s)

Ec

(MV/cm)

Vsat

(107 cm/s)

λ

(W/cm∙k)

Direct/

Indirect

Si 1.1 1.5e10 11.8 1350 0.3 1.0 1.5 I
Ge 0.66 2.4e13 16.0 3900 0.1 0.5 0.6 I
GaAs 1.4 1.8e6 12.8 8500 0.4 2.0 0.5 D
GaP 2.3 7.7e-1 11.1 350 1.3 1.4 0.8 I
InP 1.86 ~1e3 9.6 3000 1.0 2.5 - D
GaN 3.39 1.9e-10 9.0 900 3.3 2.5 1.3 D
3C-SiC 2.2 6.9 9.6 900 1.2 2.0 4.5 I
4H-SiC 3.26 8.2e-9 10 720a

650c

2.0 2.0 4.5 I
6H-SiC 3.0 2.3e-6 9.7 370a

50c

2.4 2.0 4.5 I
Diamond 5.45 1.6e-27 5.5 1900 5.6 2.7 20 I
BN 6.0 1.5e-31 7.1 5 10 1.0* 13 I
AlN 6.1 ~1e-31 8.7 1100 11.7 1.8 2.5 D

Si = Silicon

Ge = Germanium

GaAs = Gallium Arsenide

GaP = Gallium Phosphide

InP = Indium Phosphide

GaN = Gallium Nitride

3C-SiC = Zinc Blende (Cubic) Silicon Carbide  T2d-F43m

4H-SiC = Wurtzite (Hexagonal) Silicon Carbide  C46v-P63mc

6H-SiC = Wurtzite (Hexagonal) Silicon Carbide  C53v-R3m

BN = Boron Nitride

AlN = Aluminum Nitride

a = mobility along the a-axis

c = mobility along the c-axis

* = estimate

Data Source = Proceedings of IEEE,

                      Vol. 90, No. 6, June 2002

 

Properties of SiC