• USA & Canada (866) 727-8376
  • International +1 (949) 261-1920

Pasternack Blog

Roundup of RF Transistor Types, Semiconductors, and Configurations

The growing number of RF, microwave, and millimeter-wave applications has led to a growth in the number of RF transistor types, semiconductors, and configurations being used today. Future developments on these technologies are also ongoing, as competition in wireless communications, satellite communications, radar, sensing, test and measurement, and other applications grows. As more devices used RF/wireless technology to communicate and sense, there will be an even greater diversity of RF transistor technologies. Some of the RF transistor types, configurations, and semiconductors have been in use for decades, and are often still used in certain niche applications, while other nuances of RF transistor technology have recently reached the market and are enabling new applications.

In essence, there are three categories of RF semiconductor technologies, small-signal, switching, and power transistors. Certain RF transistor types and semiconductor configurations are best suited to certain applications, which is why there is such a diversity of configurations. Small-signal technologies are typically used for low-noise signal processing and amplification, where power transistors are used for high-gain and high power applications. Switching transistors are used for their ability to rapidly be set to conduction-/off-states with minimal transient performance degraded factors. As most RF transistors are used to make amplifiers, there are three main categories of amplifiers, low-noise amplifiers, gain block amplifiers, and high power amplifiers.

RF Transistor Types

• Bipolar Junction Transistor (BJT)
• Heterojunction Bipolar Transistor (HBT)
• Insulated-gate Bipolar Transistor (IGBT)
• High Electron Mobility Transistor (HEMT)
• Pseudomorphic HEMT (pHEMT)
• Enhancement Mode pHEMT (E-pHEMT)
• Field Effect Transistor (FET)
• Junction Gate Field Effect Transistor (JFET)
• Metal Oxide Semiconductor FET (MOSFET)
• Metal-Semiconductor FET (MESFET)
• Linear Diffusion MOSFET (LDMOS)
• Vertical Double Diffused MOSFET (VDMOS)
• Si Bipolar COmplementary Metal Oxide Semiconductor (Si BiCMOS)

RF Transistor Semiconductors

• Silicon (Si)
• Silicon-on-insulator (SoI)
• Silicon Carbide (SiC)
• Indium Phosphide (InP), Indium Aluminum Arsenide (InAlAs), or Indium Gallium Arsenide (InGaAs)
• Gallium Arsenide (GaAs) or Aluminum GaAs (AlGaAs)
• Gallium Nitride (GaN) or Aluminum GaN (AlGaN)
• Silicon Germanium (SiGe)

Table: Common Semiconductor Properties
Material Bandgap

(eV) ~300K

Saturated Electron Velocity (x10^7 cm/s) Electron Mobility (cm2/Vs) Critical Field Ec

(V/cm)

Thermal Conductivity

(W/m·K)

Coefficient of Thermal Expansion (ppm/K) Power Device Figure of Merit

(u_n*E_c^3)

Dielectric Constant

(epsilon_r)

InSb 0.17, D 77,000 1,000 18 5.37
InAs 0.354, D 44,000 40,000 27 4.52
GaSb 0.726, D 3,000 50,000 32 7.75
InP 1.344, D 1 5,400 500,000 68 4.6 12.5
GaAs 1.424, D 1 8500 400,000 55 5.73 20 12.8
GaN

(AlGaN/GaN)

3.44, D 1.5 900-2000 3,000,000 110

(200 Film)

5.4-7.2 3000 9
Ge 0.661, I 3,900 100,000 58 5.9
Si 1.12, I 1 1,400 300,000 130 2.6 1 11.8
GaP 2.26, I 250 1,000,000 110 4.65
SiC (3C, b) 2.36, I ~2 300-900 1,300,000 700 2.77
SiC (6H, a) 2.86, I ~2 330 – 400 2,400,000 700 5.12
SiC (4H, a) 3.25, I ~2 700 3,180,000 700 5.12 675 10
C (diamond) 5.46-5.6, I 2,200 6,000,000 1,300 0.8

 

Common RF Transistor Configurations

GaN (AlGaN/GaN)

> GaN on GaN
> GaN on Diamond
> GaN on Si
> GaN on SiC
> GaN HEMT

GaAs

> GaAs FET
> GaAs IGBT
> GaAs MESFET
> AlGaAs/GaAs HEMT
> GaAs pHEMT

InP

> InP HEMT
> InP HBT

SiC

> SiC MESFET
> SiC MOSFET

SiGe

> SiGe HBT
> SiGe/SiC (SiGe:C)

Si

> Si MOSFET
> Si LDMOS
> Si VDMOS
> Si BJT (Si-Bipolar)
> SoI
> Sapphire-on-Silicon (Ultra CMOS)
> Si BiCMOS

Learn more about Pasternack’s expansive line of RF, microwave, and millimeter-wave amplifiers here.