SEMICONDUCTORS

Semiconductors can be defined as a material that has both electrical conductivity values falling between that of a conductor, like copper, and an insulator, like glass. This property arises due to the presence of a bandgap, which is a range of energies that electrons cannot occupy within the material. This makes it possible to control the flow of electrons in semiconductors, which is essential for many electronic applications.

Types of Semiconductors

Semiconductors are typically made from materials such as silicon, germanium, and gallium arsenide. They can be classified into two types: intrinsic and extrinsic.

• Intrinsic semiconductors are made of pure materials that have no impurities or doping agents. They have a relatively low conductivity, as their valence and conduction bands are separated by a relatively large energy gap. Intrinsic semiconductors are not suitable for most electronic applications, as they require very high voltages to operate.
• Extrinsic semiconductors, on the other hand, are made by adding impurities or doping agents to pure materials. This process creates a material with more desirable electronic properties, such as higher conductivity and improved control over electron flow. Extrinsic semiconductors can be further classified into two types: n-type and p-type.
  • N-type semiconductors are doped with impurities such as phosphorus or arsenic, which have one more valence electron than the semiconductor material. This creates extra electrons in the material, which are known as "donors." These extra electrons make n-type semiconductors more conductive.
  • P-type semiconductors, on the other hand, are doped with impurities such as boron or aluminum, which have one less valence electron than the semiconductor material. This creates "holes" in the material, which act as mobile positive charges. These holes make p-type semiconductors more conductive.

In electronics engineering, semiconductors are normally classified according to their functionality, as a result, we have we have split them into 3 broad types:

• Discrete semiconductors
• Integrated Circuits (ICs)
• Wireless modules

Applications of Semiconductors:

Semiconductors are used in a wide range of applications, from simple electronic circuits to advanced computer processors. They are also used in solar cells, LED lighting, and sensors. Some specific examples of semiconductor applications include:

• Microprocessors: These are the "brain" of a computer, and are made from billions of transistors, which are tiny semiconductor devices. The ability to pack more transistors onto a chip has led to significant improvements in computing power and energy efficiency.
• Memory chips: These are used to store data in electronic devices, such as smartphones and laptops. Different types of memory chips, such as DRAM and flash memory, use different types of semiconductor technology to achieve different levels of speed, capacity, and cost-effectiveness.
• LEDs: These use semiconductors to convert electrical energy into light energy, and are used in everything from traffic lights to television screens. Advances in LED technology have led to significant improvements in energy efficiency and color quality.
• Solar cells: These use semiconductors to convert sunlight into electricity, and are used in renewable energy systems. Improvements in semiconductor technology have led to significant reductions in the cost of solar cells, making them more competitive with traditional energy sources.

Application / Industries that Use Semiconductors:

Semiconductors are used in a wide range of industries, from consumer electronics to healthcare. Some of the major industries that use semiconductors include:

• Computing: Semiconductors are used in computer processors, memory chips, and other components that are essential to computing. The ability to pack more transistors onto a chip has led to significant improvements in computing power and energy efficiency.
• Telecommunications: Semiconductors are used in devices such as smartphones and tablets, as well as in networking equipment like routers and switches. Advances in semiconductor technology have led to significant improvements in wireless communication and data transfer speeds.
• Automotive: Semiconductors are used in a wide range of automotive applications, including engine control units, infotainment systems, and advanced driver assistance systems (ADAS). Advances in semiconductor technology have enabled the development of more sophisticated and reliable automotive systems.
• Aerospace and Defense: Semiconductors are used in a variety of applications in the aerospace and defense industries, such as avionics, communications systems, and missile guidance systems. The high reliability and performance of semiconductors make them ideal for these critical applications.
• Healthcare: Semiconductors are used in medical imaging systems, such as MRI and CT scanners, as well as in diagnostic devices and implantable medical devices. Advances in semiconductor technology have enabled the development of more accurate and effective medical devices.

Popular Brands that Manufacture Semiconductors:

There are many companies that manufacture semiconductors, ranging from large multinational corporations to smaller specialised firms. Some of the most well-known companies in this field include:

• Intel: One of the largest semiconductor manufacturers in the world, Intel is known for producing microprocessors and other computer components.
• Samsung: A major player in the semiconductor industry, Samsung produces a wide range of memory chips, processors, and other components.
• TSMC: A Taiwanese semiconductor manufacturer, TSMC is known for producing advanced microprocessors and other high-performance components.
• Broadcom: A US-based semiconductor company, Broadcom produces a wide range of components for the computing, networking, and telecommunications industries.
• Qualcomm: A leader in wireless communications technology, Qualcomm produces semiconductors for smartphones, tablets, and other wireless devices. Texas Instruments: Produces a wide range of semiconductors for various applications, including automotive and industrial use.
• Onsemi: A major producer of semiconductors used in Automotive, Industrial, Telecommunication, Medical, Aerospace & defense
• STMicroelectronics: Produces semiconductors for personal electronics, IoT application, Communication equipment, embedded systems, Industrial & Automotive.