1. Bipolar Devices

Bipolar Devices are semiconductors devices in which both electrons and holes participate in the conduction process.

• Bipolar Transistor
  • n-p-n
  • p-n-p

• Thyristor
  • p-n-p-n structure

2. Unipolar Devices

Unipolar devices are semiconductors devices in which only one type of carrier predominantly participates in the conduction process.

• Metal-Semiconductor contact
• JFET: Junction Field-Effect transistor
• MESFET: Metal-Semiconductor Field-Effect Transistor
• MOS Diode: Metal-Oxide Semiconductor Diode
• MOSFET: Metal-Oxide Semiconductor Field Effect Transistor

3. Microwave Devices

Microwave Devices are those semiconductor devices that can be operated in the microwave region (frequencies from 1GHz (10⁹ Hz) to 1000 Ghz (10¹² Hz)). To achieve microwave capabilities the device dimension must be reduced and the parasitic capacitance and resistance must be minimized,

• Tunnel Diode: Related to the quantum tunneling phenomena
• IMPATT Diode: Impact Ionization Avalanche Transit Time
• BARITT Diode: Barrier Injection Transit Time
• TED: Transferred-electron device

4. Photonic Devices

Photonic devices are devices in which the basic particle of light (photon) plays a major role.

• LED: Light-Emitting diode
• Laser: Light Amplification by Stimulated Emission of Radiation
• Photodetector: (Used to detect optical signals)
• Solar cell: (Used to converts optical energy into electrical energy)