AVS 52nd International Symposium
    Plasma Science and Technology Monday Sessions
       Session PS-MoP

Paper PS-MoP2
Optical Second Harmonic Generation during Ar@sup +@ Etching of Silicon

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Plasma Science and Technology Poster Session
Presenter: P.M. Gevers, Eindhoven University of Technology, The Netherlands
Authors: P.M. Gevers, Eindhoven University of Technology, The Netherlands
A.A.E. Stevens, Eindhoven University of Technology, The Netherlands
J.J.H. Gielis, Eindhoven University of Technology, The Netherlands
H.C.W. Beijerinck, Eindhoven University of Technology, The Netherlands
M.C.M. Van De Sanden, Eindhoven University of Technology, The Netherlands
W.M.M. Kessels, Eindhoven University of Technology, The Netherlands
Correspondent: Click to Email
Plasma etching of crystalline silicon can create a damaged layer in the top region of the silicon due to ion bombardment. Defects like strained and dangling silicon bonds are expected to be abundant in this region. The surface and interface sensitive nonlinear optical technique of second harmonic generation (SHG) is known to probe these defects in crystalline silicon and is therefore applied to study the plasma etching process. To circumvent the complexity of the plasma, the experiments are performed in a UHV multiple-beam setup, containing an ion source producing Ar@sup +@ ions with energies ranging from 20 eV to 2.5 keV. The data presented here will discuss the SH-signal in the photon energy range of 2.70-3.44 eV probing the strain-induced resonance. The silicon SH-signal exhibits an enormous increase when subjected to Ar@sup +@ ions. Careful analysis has localized the origin of the signal to both the surface of the silicon and the interface between the damaged and crystalline silicon. Future application of this diagnostic in the ion induced etching process promises to aid in the understanding of the etching process and might supply the possibility of monitoring the defects induced during processing.