Langmuir probe measurements in an ICP

In the last years, interest for high densities etching sources has rose dramatically in the semiconductor industry. Process machines need to be adapted to the manufacturer leitmotiv " as small as possible" and achieve at the same time a high aspect ratio of the etched layers. Low pressure Inductively Coupled Plasma (ICP) sources proved to be a better candidate for that purpose than capacitively coupled plasma (CCP) sources. Their advantage is that they are intrinsically capable of producing high density plasmas and of independently controlling the energy of the particles (with an additional bias) when they reach the substrate electrode. In this study we had a look with a Langmuir probe on the validity of this affirmation in our vessel. We performed a quite exhaustive study concerning the influence of the plasma conditions such as gas pressure, source power, radial position and bias on the plasma parameters. However we will only present in that abstract the influence of the bias on the bulk plasma parameters (the rest of the results will be presented in the conference).