Application of a two-step growth to the formation of epitaxial CoSi2 filmson Si(001) surfaces: Comparative study using reactive deposition epitaxy

Hayashi, Y Katoh, T Ikeda, H Sakai, A Zaima, S Yasuda, Y

Y. Hayashi et al., Application of a two-step growth to the formation of epitaxial CoSi2 filmson Si(001) surfaces: Comparative study using reactive deposition epitaxy, JPN J A P 1, 40(1), 2001, pp. 269-275

25

INGLESE

Article

Apllied Physucs/Condensed Matter/Materiales Science

JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS → ACNP

40

1

2001

269 - 275

ISI

0021-4922(200101)40:1<269:AOATGT>2.0.ZU;2-W

Epitaxial growth of 20-nm-thick CoSi2 films on Si(001) surfaces has been in vestigated for a two-step growth and reactive deposition epitaxy (RDE) at g rowth temperatures of 320-680 degreesC using in-situ reflection high-energy electron diffraction and scanning tunneling microscopy, and ex-situ X-ray diffraction and atomic force microscopy. For the RDE, three-dimensional CoS i2 islands with a {115}-faceted structure grow along the (110) directions a nd pinholes or channels with depths over similar to 20 nm are formed. Howev er, for the two-step growth, no {115}-faceted islands exist and the depth o f pinholes or channels decreases greatly. In the two-step grou'th, cobalt i s solely deposited at an elevated substrate temperature on an epitaxial CoS i2(001) film formed by solid-phase epitaxy of 0.23-nm-thick Co as the first step. The first-step CoSi2 him has effects on restraining the Si diffusion from the substrate at the pinhole sites and promoting the layer-by-layer g rowth at the second step. The original two-step growth technique will be hi ghly suitable for the realization of high-quality epitaxial CoSi2 contacts in the future ULSI technology.