The dust particles introduced into plasma are charged by the influx of electrons, ions, and the dust. charge is one of the most fundamental and important parameters in the dynamical behavior of the particle inside the plasma. In this thesis work, measurement of micrometer sized $SiO_2$ and MF particles externally injected into a dc glow argon discharge was conducted. The charge measurement was done by the force balance acted upon the levitated particle among the upward electrostatic force and the downward gravity at the levitation position. For doing it, a parabolic sheath model was used to obtain the sheath electric field. On the other hand, the electric field profile around the levitated position was also measured by using an emissive probe. The particle charge was also experimentally obtained by measuring the resonance frequency of the particle oscillation motion driven by an excitation wire inserted into the plasma. Finally, the particle charge was evaluated by using a self-consistent collisional plasma sheath model and the OML (orbital motion limited) theory at the given experimental plasma condition. The particle charge measured by the three different methods turned out to produce about the same order of magnitude, which is several times smaller than that obtained by the modeling.
플라즈마 내에 트랩된 티끌입자는 전자, 이온, 티끌입자들의 플럭스에 의해 전하를 띄게 된다. 전하량은 플라즈마 내에 부유하는 티끌입자의 거동을 연구하는데 있어서 중요한 변수이다. 본 연구에서는 마이크로미터 크기의 입자들을 DC 글로우 아르곤 플라즈마에 삽입하여 전하량을 측정하였다. 전하량 측정은 포물선 덮개 모델로부터 전기장을 계산한 결과와 방출탐침을 이용하여 트랩된 위치에서의 전기장을 직접 측정하여 전하량을 측정한 실험으로 수행하였다. 실험을 통한 전하량 크기와 이론적인 계산으로 구한 전하량 크기도 비교하였다. 비교 결과 실험을 통한 전하량의 크기가 이론으로 구한 전하량의 크기보다 작은 결과가 나왔다.
