AVS 47th International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuP

Paper PS-TuP5
The Study of Optical Emission Spectroscopy in SrBi@sub 2@Ta@sub 2@O@sub 9@ Etching Using Inductively Coupled Plasma

Tuesday, October 3, 2000, 5:30 pm, Room Exhibit Hall C & D

Session: Poster Session
Presenter: S.U. Shin, Chungang University, Korea
Authors: S.U. Shin, Chungang University, Korea
D.P. Kim, Chungang University, Korea
E.-G. Chang, Chungang University, Korea
C.-I. Kim, Chungang University, Korea
Correspondent: Click to Email
Recent developments in real-time optical emission spectroscopy (OES) for plasma diagnostics are critically mentioned. The OES results also suggest certain chemical reactions to take place in the plasma, which can be correlated to the chemical composition of the films. In this report, since the research of SrBi@sub 2@Ta@sub 2@O@sub 9@ (SBT) thin film etching was few(specially Cl@sub 2@-base ), we had studied the surface reaction of SBT thin films using the OES in high density plasma etching. Measurements were made as a function of input power, pressure, bias power, and as a function of gas ratio for Cl@sub 2@ and Ar. It had been found that this SBT etch rate appeared to be more affected by the physical sputtering between Ar ions and surface of the SBT compared to the chemical reaction in our previous papers. The change of Cl radical density measured by the OES as a function of gas combination showed the change of the SBT etch rates, therefore, chemical reactions between Cl radical in plasma and components of the SBT enhanced to increase the SBT etch rates. According to the OES spectra, Ar ion bombardment strongly effects to remove Sr, Bi, and Ta atoms, however, some of the Bi and Ta atoms react with Cl radicals and form a little of BiCl@sub x@ and TaCl@sub x@, respectively. The surface residues remaining after the etch were investigated using XPS and SIMS for all of the etch conditions used in the experimental since the SBT etching process is dominant physical Ar ion bombardments and forms nonvolatile compound. These datum can be used to confirm our previous results of the OES. The plasma density and electron temperature of inductively coupled plasmas were determined by Langmuir probes. The OES results provided a strong support to the etching mechanism in inductively coupled plasma can be used to monitor the chemical and energetic properties of the plasma, providing a basis for control of industrial process.