This article explains how semiconductors are so deeply involved in our daily lives, and introduces you to their principles, functions, and various applications. Semiconductors are able to control the flow of electric current by the direction of the voltage, which allows them to power and control electronic devices. Semiconductors are applied to various devices, from computer CPUs to LEDs, digital cameras, and thermostats, and the book also discusses the development of Korea’s semiconductor industry and its future possibilities.
A man wakes up in the morning to the sound of his alarm clock. He turns on the TV with the remote control to watch the morning news, shaves with an electric razor, and washes his face in the bathroom with an automatic sensor. Ready for work, he takes the bus to his office. When he arrives at work, he starts working on his computer and works in an air-conditioned office with a coffee pot. He occasionally receives texts on his cell phone. At the end of the day, he returns home and enjoys his free time on his laptop. Would you believe it if I told you that all of these devices contain semiconductors? We live in a sea of semiconductors, and it’s no exaggeration to say that we live in a “semiconductor kingdom.” However, we still don’t know much about the semiconductors that have become so ingrained in our daily lives. We often don’t even know how they are made, how they work, or what they are used for. In this article, we’ll take a look at how semiconductors work and what they’re used for.
A semiconductor is basically a device that allows electric current to flow in response to an external stimulus called a voltage. Just as water flows in the direction of the wind in a river, electrons and holes in a semiconductor create an electric current. Electrons have a negative (-) charge and holes have a positive (+) charge, so they move in opposite directions when current flows. For example, when current flows to the right, holes move to the right, electrons move to the left, and so on. However, these particles don’t always move in a fixed direction. Just like humans need to eat food to work, electrons and holes need to be energized by a voltage to move. This voltage causes the electrons and holes to move, allowing current to flow through the semiconductor.
At this point, it seems like semiconductors are like conductors that allow current to flow through them. But why do we call them “semiconductors”? A conductor is a material that allows current to flow through it, while a semiconductor is a material that allows current to flow through it or block it as needed. The word “semi” doesn’t mean that it only allows current to flow half the time, but rather that the current flow varies depending on the conditions. Semiconductors also have + and – polarity, which means that when a voltage is applied in a certain direction, current flows, and when it is applied in the opposite direction, current is blocked. It’s like walking on a moving walkway, if you’re moving in the right direction, you can walk fast, but if you’re moving in the wrong direction, you’re stuck in place. Similarly, the direction of the voltage across a semiconductor determines the flow of current.
This property of semiconductors allows them to perform power functions that are essential to many electronic devices. For example, you can imagine how inconvenient it would be if you had to unplug everything every time you turned off your computer. In addition to power, semiconductors also act as switches inside electronics, allowing for fine-tuning of functions. The reason we can watch an LCD TV is because the tiny bulbs on the screen turn on and off in a specific sequence, and the way a fan or air conditioner blows is also controlled by semiconductors. The switching capabilities of semiconductors have become one of the core technologies of modern electronics.
The range of applications for semiconductors is very broad. As you can see from the examples above, almost every device in our daily lives contains semiconductors. Together, they make up a circuit, and multiple circuits make up a chip, which performs a specific function. Thermostats, pressure sensors, graphics cards, and many other devices are made up of these chips. Devices that produce light, such as LEDs, also utilize semiconductors and are used in light bulbs and LED TVs. The camera in your digital camera or cell phone can take photos or videos in response to light sensitivity, and the CPUs in computers and calculators are also made of semiconductor circuits. Semiconductors play a key role in many industries and perform a variety of functions depending on their use.
So far, we’ve learned about the principles and uses of semiconductors. We’ve seen that this seemingly simple principle plays a very important role in real life, and its scope is much wider than we could have imagined. We are already living in an era where it is difficult to live 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 is also the reason why Samsung Electronics and LG Electronics have been able to grow into world-class companies. In the future, the semiconductor industry is expected to continue to develop through technological innovation. We can expect our lives to be enriched by the advancement of semiconductor technology.
