The elements that form the Earth appear in the form of solids, liquids, and gases, transitioning between states thereof with changes in temperature. When there is more energy applied to these three basic state, it becomes the plasma. A plasma is formed when there are equal amounts of ionized particles and electrons, called a quasi-neutral state. Plasma with various properties is used in various applied sciences, industries, and medical fields. When artificially generated plasma is used for industrial or medical use, it can be divided into high temperature or thermal plasma and cold plasma according to the temperature. High-temperature plasma is mainly used for industrial purposes such as nuclear fusion, incineration, and metal cutting, whereas low-temperature plasma is used for light-emitting sources, medical fields, and equipment. The most typical characteristic of plasma is the radicals that are generated in various ways. the radicals generated by plasmas are thought to be more effective in killing cancer cells or sterilizing bacteria. Various radicals generated in the plasma destroy the cell wall of bacteria and have a strong sterilizing effect and interestingly, living tissues are hardly damaged under the same conditions. Therefore, plasma has a very good effect on bacterial-infected tissues, thereby can speed up the wound healing process. In particular, interest in plasma for dermatological treatment is increasing, and cases of use for wound healing have been reported in the UK and Germany. In addition, recently, cases of use in acne, athlete's foot, freckles, and atopy have been continuously reported, and as interest in plasma has increased, efforts to apply it to various skin treatments are increasing. Plasma will continue to be actively researched in more fields in the future. Through such efforts, it will be necessary to develop purpose-built plasma generating devices that are easier and more convenient to use. Furthermore, additional research is needed to determine how unstable plasma energy can be accurately adjusted and to develop quantitative methods with which to measure radicals present in a plasma.

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Keywords: Plasma, Radicals, Nitrogen, Argon