AVS 53rd International Symposium
    Electronic Materials and Processing Thursday Sessions
       Session EM-ThP

Paper EM-ThP49
Influence of the Bottom Electrode Material in Y@sub 2@O@sub 3@ MIM Capacitors

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Electronic Materials and Processing Poster Session
Presenter: M. Bonvalot, LTM/CNRS, France
Authors: M. Bonvalot, LTM/CNRS, France
M. Kahn, LTM/CNRS, France
C. Vallee, LTM/CNRS, France
J. Ducote, LTM/CNRS, France
O. Joubert, LTM/CNRS, France
Correspondent: Click to Email
High quality MIM capacitors are seeing increased use in CMOS, BICMOS and bipolar chips. The economic demand for smaller devices directly leads to the request for higher MIM charge storage densities. Therefore new high @kappa@ dielectric materials, such as Al@sub 2@O@sub 3@, Ta@sub 2@O@sub 5@ and HfO@sub 2@, are being evaluated as MIM dielectrics and will be used in future applications. Nevertheless, most of these materials show very large variations of their capacitance with applied bias voltage (so-called voltage linearity, characterized by a quadratic coefficient - alpha); thus, they cannot be used for analog MIM applications. TiN/Y@sub 2@O@sub 3@/Au capacitors have already been investigated. They exhibit good electrical properties with large breakdown electrical field values (7-8 MV/cm), low leakage currents, and a capacitance density of 5 fF/µm@super 2@. The Y@sub 2@O@sub 3@ is grown by pulsed liquid injection MOCVD. The aim of the present work is to study the impact of the bottom electrode materials on the interfacial layer between the metal and the yttrium oxide and hence, on the MIM electrical properties (C(V) and I(V) characterizations). Several electrode materials will be put on trial, such as WSi@sub x@(x=1, 2, 3), Ni and Pt. Their influence on the interface will be chemically characterized by means of XPS, SE in the FUV-visible range (up to 8 eV), and SIMS. The electrical behavior C(V) will be analyzed based on the work function of the metal electrode and on the nature of the interface with Y@sub 2@O@sub 3@.