SEMICONDUCTOR DEVICES-A semiconductor device is an electronic component, such as a diode or transistor

 

                    SEMICONDUCTOR DEVICES-A semiconductor device is an electronic component, such as a diode or transistor

A semiconductor device is an electronic component, such as a diode or transistor, made from semiconductor materials like silicon that have conductivity between a conductor and an insulator. Their unique properties allow them to control the flow of electricity, forming the basis for essential electronic functions like switching and amplification. These devices are used in discrete components (like sensors or emitters) and integrated circuits (ICs), enabling the complex electronics found in almost all modern technology. 

How they work

·        Intermediate conductivity: Unlike pure conductors (like metals) or insulators (like glass), semiconductor materials have a conductivity that can be precisely controlled.          

·         Doping: By adding impurities to pure semiconductor materials, a process called doping, their electrical properties can be altered to make them more conductive or more insulating, depending on the needs of the device.

·         Switching and Amplification: The controlled conductivity allows these devices to act as electronic switches (turning current on or off) and amplifiers (increasing the strength of a signal), which are fundamental functions in electronics. 

   Types of Semiconductor Devices

1.       Discrete Semiconductors: Single devices with a specific function, such as diodes (for one-way current flow) or transistors (for switching and amplifying).

2.       Integrated Circuits: Complex devices that contain thousands or even billions of individual electronic elements, including transistors and other components, all built on a single semiconductor chip.

Ø  Semiconductor devices are classified into diodes (two-terminal devices like Light-Emitting Diodes or LEDs, Zener diodes, and solar cells) and transistors (three-terminal devices like Bipolar Junction Transistors or BJTs and Field-Effect Transistors or FETs). Other types include photo transistors, Laser diodes, like MOSFETs and IGBTs and complex ICs.

v  Two terminal Devices:

                 These devices have one positive-negative (p-n) junction and control the flow of current. 

1.       Rectifier Diode: Converts alternating current (AC) to direct current (DC). 

2.       Light-Emitting Diode (LED): Emits light when current passes through it. 

3.       Zener Diode: Allows current to flow in the reverse direction at a specific voltage, used for voltage regulation. 

4.       Photo cell/photo diode: Converts light into an electrical signal. 

5.       Laser Diode: Generates a focused beam of coherent light. 

 

6.       Solar cell: Converts sunlight into electricity. 

7.        Scotty Diode:  Has a fast switching speed. 

8.       PIN Diode: Features a distinct intrinsic layer between the p-type and n-type layers, offering specific applications in high-frequency circuits. 

v Three-Terminal Devices (Transistors

              These devices can amplify or switch electronic signals. 

1.       Bipolar Junction Transistors (BJT): Uses both electrons and holes as charge carriers. 

2.       Field Effect Transistors (FET): Controls the current flow through an electric field; a key type is the Metal Oxide Semiconductor Field Effect transistor.

3.       Power Semiconductors: High-power devices such as MOSFETs and Insulated Gate Bipolar transistors (IGBTs) used in power electronics. 

§  Integrated Circuits (ICs): Also known as microchips or chips, these are complex circuits containing many semiconductor     components on a single substrate. 

§  OPTO Electronic Devices: Devices that emit, detect, or control light, including LEDs, laser diodes, and photodiodes. 

Advantages of Semiconductor Devices:

Ø  High Efficiency

Ø  Miniaturization

Ø  Longer Life Span& reliability

Ø  Fast switching Speed

Ø  No Warm up time

Ø  Mechanical Robustness

Ø  Integration into ICs

Ø  Versatility

Ø  Cost-Effectiveness

Ø  Low power Consumptions

Ø  Durability