Did you know that there are over 1,000 chips used in a car?
Did you also know that the number changed to over 2,000 for an EV car?
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
Semiconductors: Definition and Materials
Semiconductors are materials that conduct electricity between insulators and conductors, making them essential in electronic devices.
Unlike regular conductors (i.e., metals), whose resistivity increases with temperature, the resistivity of semiconductors decreases as their temperature rises.
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.
Types of Semiconductors
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
Unlike intrinsic semiconductors, extrinsic semiconductors have improved electrical conductivity due to doping with impurities.
- 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
Semiconductor products are used in various applications, from computers to medical imaging. Examples include:
1. Microprocessor Unit (MPU)
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.
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)
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.
Conclusion
The semiconductor industry is crucial for driving global economic growth and technological advancement. However, it faces challenges such as geopolitical tensions, supply chain issues, and difficulties in creating smaller semiconductor sizes. Overall, exploring this industry further could be highly beneficial.