In this blog post, we will look at the principles and roles of semiconductors hidden in the devices we use every day, and how important they are in our daily lives.
A man wakes up to the sound of his alarm clock in the morning. He turns on the TV with the remote control to watch the morning news, shaves with an electric shaver, and then goes into the bathroom where the automatic sensor activates the sink. After getting ready for work, he takes the bus to the company. As soon as he arrives at the company, he starts working on his computer, and works in an office equipped with an air conditioner and a coffee pot. He sometimes receives text messages on his mobile phone. After finishing his work for the day, he enjoys his free time on his laptop. Would you believe that all of the devices mentioned so far contain semiconductors? As such, we are living in a sea of semiconductors, and it is no exaggeration to say that the present era is the “semiconductor kingdom.” However, we still do not know much about semiconductors, which are deeply embedded in our daily lives. Many people do not even know how semiconductors are made, how they work, or what they are used for. In this article, we will look at the principles and applications of semiconductors.
A semiconductor is basically a device that allows electric current to flow when it receives an external stimulus called voltage. Just as water flows in the direction of the wind when there is wind in a river, electrons and holes in a semiconductor create electric current and flow. Electrons have a negative charge and holes have a positive charge, so they move in opposite directions when electric current flows. For example, when an electric current flows to the right, the positive holes move to the right and the electrons move to the left. However, these particles do not always move in a fixed direction. Just as a person needs to eat in order to work, electrons and positive holes can only move when they receive energy in the form of voltage. This is how voltage moves electrons and positive holes and causes electric current to flow in a semiconductor.
So far, semiconductors seem to be like conductors that allow electric currents to flow. Then why are they called “semiconductors”? Conductors are substances that allow electric currents to flow well, while semiconductors are substances that allow electric currents to flow or be blocked as needed. In other words, the meaning of “semi” does not mean that only half of the electric current flows, but that the flow of electric current varies depending on the conditions. Semiconductors also have a polarity of + and -, and when voltage is applied in a specific direction, current flows, and when it is applied in the opposite direction, current is blocked. If the direction of a person’s movement on a moving walk is correct, they can walk quickly, but if they move in the opposite direction, they will be stuck in place. Similarly, the direction of voltage determines the flow of current in semiconductors.
This property of semiconductors enables the power supply function that is essential for various electronic devices. For example, if you imagine having to unplug all the plugs every time you turn off your computer, you can guess how inconvenient it would be. Semiconductors not only function as a power source, but also act as a switch inside electronic devices, allowing the functions to be adjusted in detail. The reason we can watch LCD TVs is because the small light bulbs on the screen turn on and off in a specific order. The wind strength of a fan or air conditioner is also controlled by the operation of semiconductors. As such, the switch function of semiconductors is becoming one of the core technologies of modern electronic devices.
Semiconductors have a very wide range of applications. As mentioned earlier, almost all devices in our daily lives contain semiconductors. Semiconductors are assembled to form a single circuit, and multiple circuits are assembled to form a single chip to perform a specific function. Various devices such as temperature control devices, pressure sensors, and graphics cards are composed of these chips. Light-emitting devices such as LEDs are also made using semiconductors and are used in light fixtures and LED TVs. Digital cameras and mobile phone cameras can take photos and videos in response to the light sensitivity, and the CPU of computers and calculators is also made of semiconductor circuits. As such, semiconductors play a key role in various industries and perform various functions depending on their use.
So far, we have learned about the principles and uses of semiconductors. We have seen that the seemingly simple principles play a very important role in actual use, and that their scope is wider than we could have imagined. We are already living in an era where life is difficult without semiconductors. Korea is also leading the world in the semiconductor industry, which is an important pillar of the country’s growth engine. The development of the semiconductor industry was also behind the growth of Samsung Electronics and LG Electronics into global companies. The semiconductor industry is expected to continue to develop through technological innovation. It would be nice to look forward to our lives becoming more affluent with the development of semiconductor technology.
