Self‐recovery function of p(1×1)‐Sc‐O/W(100) system used as Schottky emitter

Abstract

The effects of heating temperature for the preparation of an Sc-O/W(100) surface were investigated. Surface properties of the Sc-O/W(100) surface prepared by heating at ∼1600 and ∼1700 K were significantly different from those prepared at ∼1500 K, which is the operating temperature of the Sc-O/W(100) emitter. By heating at ∼1700 K the p(1×1) structure formed by Sc-O complexes was confirmed, whereas the p(2×1)-p(1×2) double-domain structure was obtained by heating at ∼1500 K. The surface properties prepared by heating at ∼1700 K were found to be very stable, and the surface has a self-recovery function against residual gas ion sputtering at the operating temperature of the emitter. The present results strongly suggested that pretreatment of the Sc-O/W(100) emitter by heating at ∼1700 K and device operation at ∼1500 K result in high reproducibility of the superior electron emission property of the Sc-O/W(100) emitter.

Kinetics of surface atoms during phase transition of Sc–O/W(100) system at high temperature studied by Auger electron spectroscopy

“…Previous studies [4][5][6][7][8][9][10][11][12][13] have revealed that the Sc-O/W(1 0 0) surface has two phases with surface atomic arrangements of the (1 Â 1) and (2 Â 1)-(1 Â 2) structures at high temperature. The (2 Â 1)-(1 Â 2)-Sc-O/W(1 0 0) surface is formed by heating at 1500 K in oxygen atmosphere.…”

“…In this regard, the authors have been involved in the surface characterization of the Sc-O/W(1 0 0) system using Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), and work function measurement at high temperature [4][5][6][7][8][9][10][11][12][13]. Previous studies [4][5][6][7][8][9][10][11][12][13] have revealed that the Sc-O/W(1 0 0) surface has two phases with surface atomic arrangements of the (1 Â 1) and (2 Â 1)-(1 Â 2) structures at high temperature.…”

Study on Low-Temperature Emission Performance of Scandate Cathode with Micro-Blade-Type Arrays

“…The zirconium and oxygen adsorbed onto the cathode surface also reduced the work function; thus, the cathode emission current was greatly increased. Lida, S and Nagatomi, T studied a type of Sc-O/W(100) emitter used as Schottky emitter [38]. Their research indicated that Sc-O complexes have a lower work function and self-recovery function against residual gas.…”

In situ observation of change in surface atomic arrangement of Sc–O∕W(100) system during phase transition at high temperature

“…[6][7][8][9][10][11][12][13][14][15][16][17] Previous studies have revealed that the Sc-O / W͑100͒ system has two phases at high temperature. The surface providing the excellent electron emission properties is considered to be formed only under limited preparation and operating conditions of the Sc-O / W͑100͒ emitter.…”