In this blog post, we’ll take a natural and easy-to-understand look at the principles and types of semiconductors, their applications in everyday life, and the present and future of South Korea’s semiconductor industry.
Semiconductors are one of South Korea’s key industries today. It is no exaggeration to say that semiconductors are used in nearly every electronic device in modern society. South Korean semiconductor companies, including Samsung Electronics, hold significant positions in the global semiconductor market, and as the industry grows, more universities are establishing dedicated semiconductor-related departments. So, what exactly are semiconductors, and why are they used in such a wide range of fields?
A semiconductor is a material with electrical properties that fall between those of a conductor, which conducts electricity well, and an insulator, which conducts almost no electricity. Typical semiconductor materials include silicon and germanium. Under normal conditions, electricity does not flow easily through them, but when heat is applied or specific impurities are added, free electrons are generated, allowing electricity to flow. Electrons are negatively charged particles that orbit the atomic nucleus—the center of the atom—in specific numbers. When heat is applied, electrons gain energy and break away from the nucleus to become free electrons; when other atoms are added as impurities, the number of electrons increases or decreases. Based on these characteristics, semiconductors are classified into n-type and p-type semiconductors. An n-type semiconductor contains many free electrons, while a p-type semiconductor contains many holes. A hole is a vacancy left by an electron and has the property of seeking to accept an electron to reach a stable state. When phosphorus (P) is added to silicon, there is an excess of electrons, resulting in an n-type semiconductor; when boron (B) is added, there is a shortage of electrons, creating holes and resulting in a p-type semiconductor. Semiconductors with these characteristics are used as core components in various electronic devices.
A diode is a device created by joining an n-type semiconductor and a p-type semiconductor. In a diode, electrons can move easily only from the n-type semiconductor toward the p-type semiconductor, so current flows in only one direction. This characteristic is widely utilized in rectifier circuits. A rectifier circuit converts alternating current (AC) to direct current (DC), maintaining a consistent direction of current flow. These diodes are used in various power adapters, including cell phone chargers. AC is a current in which the magnitude and direction change periodically over time, while DC is a current that maintains a constant direction and magnitude. Since most electronic devices use DC power, the process of converting AC to DC is very important. Diodes also play a role in protecting electronic devices by blocking reverse current.
Among diodes, there are also light-emitting diodes (LEDs). LEDs operate on the principle of emitting light from the energy generated when electrons and holes recombine. Since they directly convert electrical energy into light energy, they consume less power, are highly efficient, and generate relatively little heat. Currently, LEDs are used in a wide variety of fields, including TVs, computer monitors, lighting, and various display devices. While LCD displays were widely used in the past, today a variety of display technologies—such as LCDs with LED backlights and OLEDs—are used in conjunction. Based on their high brightness, long lifespan, and excellent energy efficiency, LEDs play a vital role in a wide range of electronic products.
In addition, semiconductors serve as the core material for various electronic components, including transistors—which amplify current and voltage—and integrated circuits (ICs). Transistors are used in nearly all electronic devices, such as computers, smartphones, and telecommunications equipment, while integrated circuits, which integrate numerous transistors onto a single chip, form the foundation of modern information technology. Semiconductors are one of the cutting-edge technologies most closely integrated into our daily lives, and this field is expected to continue evolving. South Korea maintains global competitiveness in the memory semiconductor sector, and research and development into system semiconductors and advanced semiconductor technologies is actively underway. Numerous universities and research institutions are currently conducting research on semiconductor technology, and many students are consistently striving to learn about semiconductors. As long as this research and innovation continue, the future of South Korea’s semiconductor industry is expected to be even brighter.
