Simulation of Transients and Transport in Plasma Processing Reactors

In this thesis, two-dimensional (2D) and 3D hybrid models were developed to investigate transient phenomena (time variation of plasma properties) during pulsed operation of ICP reactors. Employing the 2D model, it was demonstrated that utilizing transients during pulsed operation, energetic negative ions can be extracted from pulsed ICPs that can aid in reducing charge buildup on wafers. Energetic negative ions can be extracted from Ar/Cl2 pulsed ICPs with pulsed low frequency (1--2 MHz) substrate biases. Employing the 3D model, the impact of asymmetric pumping on plasma properties during continuous wave (CW) ICP operation and the effect of transients on these flow-induced asymmetries were quantified. Asymmetric pumping results in non-uniform species densities, which then feed back through plasma conductivity making the power deposition azimuthally asymmetric. The asymmetries in plasma properties increase with increase in power and gas flow rate. Pulsed operation of ICPs improves the uniformity of plasma properties as it reduces the positive feedback between species density and power deposition. In Ar ICPs, the plasma parameters were more uniform relative to CW operation on decreasing duty cycle or pulse repetition frequency (PRF).

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical and Biomolecular Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Subramonium, Pramod

Contributors dc:contributor

• Kushner, Mark J.

• Engineering, Electronics and Electrical

Language dc:language

eng

Identifier

(MiAaPQ)AAI3111643

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82360