Growth of Al on a W(110) surface

Using low energy electron diffraction and low energy ion scattering spectroscopy, we investigated the growth mode of Al on a W(110) surface at room temperature and at 1000 K. We found that Al grew on the W(110) surface in the Frank–van der Merwe mode when the W substrate was kept at room temperature during Al deposition. It was found that at a coverage higher than 2 monolayer (ML) in Al grown at room temperature, Al atoms had a well-ordered face centered cubic (fcc) (111) surface. The [11¯0] direction of the Al grown at room temperature on the (111) surface was parallel to the [001] direction of the W(110) substrate surface. When the temperature of the W substrate was kept at 1000 K, the adsorbed Al atoms grew in the Volmer–Weber mode. The 1.5 ML Al/W(110) surface prepared at 1000 K shows two domains of the fcc Al(111) surfaces along with a W(110) surface. We also found that the early stage of Al film growth shows W(110) structure. However as the film becomes thicker (above 3.5–4 layers) the Al face is turned into fcc (111) face.

► We investigated the growth behavior of Al on the W(110) surface. ► Al grew in the Frank–van der Merwe mode when the W was kept at room temperature. ► Al grew in the Volmer–Weber mode when the W was kept at 1000 K. ► The Al film grown at room temperature has the (111) surface. ► [11¯0] direction on the Al(111) was the same as [001] on the W(110) substrate.