Experimental Techniques for Low Temperature Plasma Diagnostics

Strong development in application of plasmas resulted in great new number of different plasma devices. Plasmas for research, industrial, biological and medical applications can span over many orders of magnitude in pressure, power, driver frequency, size… For even most general understanding of plasma parameters specific diagnostic methods can be used. Even nominal parameters like pressure, voltage, current can be used for parametric studies and provide some understanding. Overview of different diagnostics methods for low temperature plasmas will be presented in this talk. Application of optical and electrical measurements will be shown on examples of different plasmas RF (inductive, capacitive), sputter/deposition setup, and atmospheric, complex plasmas. Most of the diagnostic approaches are based on emission measurements using Optical Emission Spectroscopy, Laser Spectroscopy and plasma imaging providing 2D information. Depending on the type of discharge dedicated diagnostics method was used targeting desirable information. Scanning technique was applied for spatial measurements of e.g. excited states, micro particles positions providing full 3D reconstruction while different time resolutions are providing e.g. very fast "phase resolved" information or even full 3D time dependent plasma Dynamics.