Model of a circuit board displaying all component

Semiconductors are critical to the world’s technology and economy as they are integrated into various electronic devices, such as cell phones, computers, televisions, cars, solar cells, and many more. As AI and IoT grow, the demand for advanced semiconductors increases, fueling competition among nations for development

Unlike regular conductors (i.e., metals), whose resistivity increases with temperature, the resistivity of semiconductors decreases as their temperature rises.

Close-up of silica semiconductor material with a textured

The most common semiconductor materials include:

  • Silicon
    It is the most common material due to its low cost and abundance.
  • Germanium, gallium arsenide, and indium phosphide
    These materials are pricier than silicon but offer higher electron mobility and a wider band gap.
  • Cadmium telluride
    This material is expensive and toxic, resulting in limited use.

There are 2 main types of semiconductors.

1. Intrinsic semiconductors

They are highly pure semiconductors with no impurities and low electrical conductivity, such as silicon and germanium.

2. Extrinsic semiconductors

  • N-type semiconductors
    This type is doped with an element that introduces extra electrons, resulting in a higher electrical conductivity than P-Type. Dopants’ examples are phosphorus-doped silicon or arsenic-doped germanium.
  • P-type semiconductors
    P-type is doped with an element with fewer electrons than the semiconductor which resulting in a lower electrical conductivity. Dopants’ examples are boron-doped silicon or gallium-doped germanium.
  • Junction semiconductors
    A combination of N-type and P-type regions, this type is regularly used in electronic devices, such as transistors and diodes. Examples are silicon diodes and bipolar junction transistors (BJTs).

About Doping

Doping is the process of adding a small quantity of an impurity atom, called a “Dopant“, to a semiconductor material to change its electrical properties. This process can increase or decrease the material’s conductivity and is essential for making semiconductor devices. Doping enables the creation of various devices, including transistors, diodes, and integrated circuits.

About Nanometer

A nanometer (nm) is a unit of length equal to one billionth of a meter and is used to measure the size of semiconductors’ transistors. Transistors are the basic building blocks of all semiconductors in different sizes. These sizes have a highly significant impact on the performance and power consumption of the semiconductor. Generally, smaller transistors lead to improved performance, enabling faster switching and lower energy consumption.

Currently, the smallest transistors are 3nm, produced by Samsung and TSMC.

Semiconductor Product Examples

1. Microprocessor Unit (MPU)

Microprocessor unit


Similar to the human brain, this semiconductor device functions as a CPU, executing instructions stored in the computer’s memory.

2. CMOS image sensor


CMOS image sensors are semiconductor devices that convert light into electrical signals, enabling image capture in cameras and other imaging devices.

Unlike a CPU, they do not perform processing functions; instead, they focus on capturing visual information.

CMOS image sensor used in camera

3. Negative-AND (NAND)

Similar to the human brain’s short-term memory, this semiconductor device stores data. NAND memory is a type of flash memory that can be erased and reprogrammed multiple times.

4. Dynamic Random-Access Memory (DRAM)

DRAM


Similar to the human brain’s long-term memory, DRAM stores data currently in active use by a computer.

However, it is volatile, meaning it loses data when power is lost.