An introduction to optical emission spectroscopy and laser-aided spectroscopy techniques for low-temperature plasma analyses

Abstract

Low-temperature plasma is a tool that has been used widely for surface modification of materials from 70’s. Such as in the microelectronic and semiconductors industries, inductively coupled plasma and capacitively coupled plasma were used for the fabrication of thin films in ultra large scale integrated circuits. In order to optimize the plasma fabrication technique, it is important to study the plasma physics and obtain quantities like atomic, ions and electron densities, temperature of electron, atomic velocity and etc. This information is indispensable in order to control the plasma during the fabrication of thin film structure at the nano-scale level. There are several techniques of plasma diagnostics available at the moment and the amount is increasing. In the present paper, we will give a brief introduction to the optical emission spectroscopy and laser-aided spectroscopy technique for plasma studies. This is an advanced technique which allows us to study the physics inside the plasma without perturbing the plasma. The basic principles of the diagnostics will be explained and some examples from the previous experimental results will be discussed.