AVS 47th International Symposium
    Electronics Tuesday Sessions
       Session EL-TuP

Paper EL-TuP14
Etch Characteristics of CeO@sub 2@ Thin Films as a Buffer Layer for the Applications of MFIS-FeRAM

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

Session: Poster Session
Presenter: C.-S. Oh, Chungang University, Korea
Authors: C.-S. Oh, Chungang University, Korea
K.-H. Kwon, Hanseo University, Korea
T.-H. Kim, YIT, Korea
C.-I. Kim, Chungang University, Korea
Correspondent: Click to Email
Cerium oxide (CeO@sub 2@) thin film has been proposed as a buffer layer between the ferroelectric film and the Si substrate in Metal-Ferroelectric-Insulator-Silicon (MFIS) structures for ferroelectric random access memory (FeRAM). CeO@sub 2@ thin film has properties of high thermal stability, high dielectric constant and good lattice match with Si. Since the etching of CeO@sub 2@ thin film has not been reported, we studied the etch characteristics of CeO@sub 2@ thin films by using high density plasma etching system. In this study, CeO@sub 2@ thin films were etched with a CF@sub 4@/Ar gas combination in an inductively coupled plasma (ICP). Mask made use of photoresist (PR). The experiment was done by controlling the etching parameters such as gas mixing ratio, radio frequency power, direct current bias, and chamber pressure. The surface reaction of the etched CeO@sub 2@ thin films was investigated with x-ray photoelectron spectroscopy (XPS) using narrow scan spectra. Ar ion bombardment is more dominant than chemical reaction between Ce and F. The results of XPS analysis were verified by results of secondary ion mass spectrometer (SIMS) analysis and results were the same. In addition, Optical emission spectroscopy (OES) was investigated to analyze density of F radical and Ar ion in plasma. Ion current density was measured by using single Langmuir probe. The etch products were also determined using a quadrupole mass spectrometer (QMS). The profile of etched CeO@sub 2@ thin film investigated with scanning electron microscopy (SEM).