Institute of Materials (E. Asia) Technical Talk

Topic: Microhardness and Residual Stress in AlN Films Prepared by Ion Beam Assisted Deposition

Speaker: Professor Yoshihisa Watanabe

Department of Materials Science and Engineering,

National Defense Academy,

Yokosuka, Kanagawa 239-8686, Japan

E-mail: ywat@cc.nda.ac.jp

Date/Time: 26 March 2001 (Monday), 3:00 - 4:00 pm

(Refreshments will be served at 2:45 pm before the Seminar starts).

Venue: LT19, NTU

 

ABSTRACT

Aluminum nitride (AlN) thin films were prepared by the ion-beam assisted

deposition method. The effect of the nitrogen ion beam energy on

microhardness and residual stresses was studied by changing the ion beam

energy from 0.2 to 1.5 keV, resulting in a different film microstructure.

Microhardness was measured by a nano-indentation method

and residual stresses were evaluated from the film curvature measured by

an optical cantilever system. All of the films were found to be in a

compressive stress state, the value of the stress decreasing with the

ion beam energy. It was also observed that the films became soft and

plastic with increasing ion beam energy. To study the effect of thermal

treatment on the relaxation of residual stresses, films prepared with

the ion beam energies of 0.2 and 1.5 keV, which show a columnar and a

granular structure, respectively, were annealed in nitrogen at 500 C.

It was found that the granular structure film is relaxed more easily

than the columnar structure film.

Curriculum Vitae

NAME: Yoshihisa Watanabe, born on June 2, 1952

NATIONALITY: Japanese

TITLE, LOCATION: Professor, Department of Materials Science and Engineering,

National Defense Academy, 1-10-20 Hashirimizu, Yokosuka, Kanagawa

239-8686, JAPAN

Tel. No.:+81-468-41-3810 ext 2204, Fax. No.:+81-468-44-5910

e-mail: ywat@cc.nda.ac.jp

EDUCATION: Kyoto University, 1975 B.E. (Department of Nuclear Engineering)

Kyoto University, 1977 M.E. (Department of Nuclear Engineering)

Kyoto University, 1977-1979 (Doctoral student)

Tohoku University, 1982, Ph.D, Physics (Excitation of Nuclear States by

Positron Annihilation)

EXPERIENCES: Research Associate, Department of Mathematics and Physics,

National Defense Academy, 1979-1984

Lecturer, Department of Mathematics and Physics, National Defense

Academy, 1984-1987

Associate Professor, Department of Mathematics and Physics, National

Defense Academy, 1987-1989

Associate Professor, Department of Materials Science and Engineering,

National Defense Academy, 1989-1994

Visiting Scholar, Department of Mechanical Engineering, University of

Washington, 1990-1991

Professor, Department of Materials Science and Engineering, National

Defense Academy, 1994-present

Principal Editor of Journal of Materials Research, Materials Research

Society, 1995-present

Head of the Advanced Materials Laboratory of National Defense Academy, 1997-present

PROFESSIONAL SOCIETIES; American Ceramics Society, American Vacuum

Society, Ceramics Society of Japan, Japan Society of Applied Physics,

Materials Research Society,

Society for Hybrid Microelectronics

AWARDS; Ceramographic 2 nd place Award, 1993.4, Ceramic Society of Japan

Excellent Paper Award, 1995.4, Society for Hybrid Microelectronics

Ceramographic 2 nd place Award, 1996.4, Ceramic Society of Japan

Current research topics; Preparation and characterization of AlN films

by ion beam assisted deposition, Preparation and characterization of

carbon films by hot filament CVD.

Authors and co-authors of more than 100 scientific papers.

Admission is free and all are welcome. For any enquiries, please contact Assoc Prof Michael Khor Khiam Aik, School of Mechanical & Production Engineering at Tel: 790 5526