GROWTH OF HCP CU ON W(100)

Hcp Cu has been grown by epitaxy on the W(100) surface. The epitaxial relationship of the hcp films is determined by RHEED as (11 (2) over b ar 0) parallel to (100) and [1 (1) over bar 00] parallel to [011]. The growth of Cu in the hcp structure is attributed to the small energy d ifference between the hcp and fee structure and the much smaller misfi t of this hcp orientation in the [1 (1) over bar 00] direction than of any fee orientation. The RHEED oscillations at 150 K show a differenc e between the period of the even and odd oscillations, that coincides with changes in UPS intensity at selected energies. The electronic str ucture of the thin him grown at 150 and 300 K shows only small differe nces, At 500 K and above. the Cu grows in high and narrow islands.