Bulletin Autumn‧Winter 1997

HlGHLIGHTS OF RGC-FUNDED PROJECTS Fig. 3 A cross-sectional transmission electron micrograph showing a buried CoSi 2 layer in silicon formed by MEVVA implantation of semiconducting FeSi 2 w i th a bandgap of 0.85eV, is p r om i s i n g fo r Si-based i n t e g r a t e d o p t o e l e c t r o n i c d e v i ce applications. 8 The researchers have also studied the magnetic properties of Fe- i m p l a n t e d Si s amp l e s b y MEVVA imp l an t a t i on and discovere d a no v e l positive magnetoresistance effect. 9 Given these results, Prof. Wo ng believes that MEVVA implantation is a technique wo r t h further investigation. The f o r ma t i on of me t al silicides w i l l be increasingly important i n IC technology of the next generation. It also has high potential for novel device applications. I n fact, it has recently been proposed that me t al s i l i c i des ma y p r o v i de a n e w a p p r o a ch t o s i l i c on nanoe l e c t r on i c s surmounting the limit of conventiona l silicon technology. 10 Reference 1. Murarka, S.R. ， Silicides for VLSI Applications, New York ： Academic Press, 1983 ； Metallization ： Theory and Practice for VLSI and ULSI, Boston ： Butterworth-Heinemann, 1993. 2. Brown, I.G .， Galvin, J.E. & MacGill ， R.A., Appl. Phys. Lett., 1985, 47, p. 358 ； Brown, I.G., Galvin , J.E., Gavin, B.F. & MacGill ， R.A., Rev. Sci. Instrum., 1986, 5 7 , p. 1069. 3. Peng ， Q., Wong, S.P., Wilson, I.H., Wang, N. & Fung, K.K .， Thin Solid Films, 1995, 2 7 0 , p. 573. 4. Peng, Q. & Wong , S.P., MRS Symp. Proa, 1996, 402， p. 487. 5. Peng, Q .， Wong, S.R, Xu, J.B. & Wilson, I.H., MRS Symp. Proc., 1996, 396 , p. 763. 6. Wong, S.R, Peng, Q., Cheung, W.Y., Guo, W.S., Xu ， J.B., Wilson, I.H .， Hark, S.K., Morton, R. & Lau , S.S .， MRS Symp. Proc., 1997, 4 3 8 , p. 307. 7. Peng, Q., Ph.D. Thesis, 1997, The Chinese University of Hong Kong. 8. Derrien, J .， Berbezier, I., Ronda, A. & Natoli ， J.Y., Appl. Surf. Sci, 1996, 92, p. 311. 9. Wong, S.P. & Cheung, W.Y., MRS 1997 Spring Meeting, paper M1.11 ， 31st March - 4th April 1997 ， San Francisco, USA ； Wong, S.P. & Cheung, W.Y.,MRS Symp. Proc., 1997 ， 475. 10. Tucker, J.R., Wang, C. & Shen, T.C., Nanotecbnology, 1996, 7， p. 275. Metal Silicides by Ion Implantation with a MEVVA Ion Source 3S