Surface structures on sputtered/annealed WC(0001)

Abstract

We use scanning tunnelling microscopy, Auger electron spectroscopy and low energy electron diffraction to study different tungsten and carbon terminated surface reconstructions on the sputtered/annealed WC(0001) surface. The tungsten terminated surface encompasses a ( 7 × 7)R19° W-trimer structure, a ( 3 × 7) reconstruction representing a transition structure from the ( 7 × 7)R19° reconstruction to a (6 × 1) phase which consists of a quadratic W overlayer on the first close-packed carbidic carbon layer. The carbon terminated WC(0001) surface consists of a single graphitic carbon layer on top of the (6 × 1) structure.

Surface Chemistry of Transition Metal Carbides

“…The Mo and W carbide surfaces have been studied using ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), − scanning tunneling microscopy (STM), , LEED, , and Auger electron spectroscopy (AES) . For example, studies of α-Mo 2 C(0001) revealed that the surface could be altered between Mo- and C-terminated simply by changing the annealing temperature .…”

“…Otani and co-workers used ARPES to show that the valence band region of a C-terminated α-Mo 2 C(0001) surface consisted of Mo 4d, C 2s, and Mo 4d−C 2p hybrid bands . Göthelid and Janin combined the STM, AES, and LEED techniques to study the structure of WC(0001) as a function of surface composition . These authors reported a variety of LEED patterns, all of which were strongly dependent on the atomic C/W ratio at the surface …”

“…Göthelid and Janin combined the STM, AES, and LEED techniques to study the structure of WC(0001) as a function of surface composition . These authors reported a variety of LEED patterns, all of which were strongly dependent on the atomic C/W ratio at the surface …”

First-principles investigation of the WC∕HfO2 interface properties

“…8,9 A number of experimental works have explored the growth of WC films using different deposition techniques. [8][9][10][11][12][13][14] In Ref. 8 tungsten carbon layers with a stoichiometric composition of W:C=1:1 were deposited on Si forming a single polycrystalline phase by dc magnetron sputtering.…”

Bridging Electrical and Structural Interface Properties: a Combined DFT-GW Approach

“…Another technologically relevant and well studied system is the WC/HfO2 stack. A number of experimental works have explored the growth of WC films using different deposition techniques [20][21][22][23][24][25][26]. In Ref.…”