Electron stimulated desorption of the metallic substrate at monolayer coverage: Sensitive detection via 193 nm laser photoionization of neutral aluminum desorbed from CH sub 3 O/Al(111)

Conference · Wed Jan 01 00:00:00 EST 1992

OSTI ID:5167958

Young, C E; Whitten, J E; Pellin, M J; Gruen, D M ^[1]; Jones, P L ^[2]

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1. Argonne National Lab., IL (United States)
2. STI Optronics, Bellevue, WA (United States)

A fortuitous overlap between the gain profile of the 193 nm ArF excimer laser and the Al autoionizing transition {sup 2}S{sub 1/2} (512753 cm{sup {minus}1}) {l arrow} {sup 2}P{sup 0}J has been exploited in the direct observation of substrate metal atoms in an electron simulated desorption (ESD) process from the monolayer adsorbate system CH{sub 3}O/Al(111). The identity of the mass 27 photoion was established as Al{sup +} by (1) isotopic substitution of {sup 13}C in the methanol employed for methoxy formation, and (2) tunable laser scans utilizing the {sup 2}DJ (J=3/2, 5/2) intermediate levels at {approximately}32436 cm{sup {minus}1} and a 248 nm ionization step. An ESD yield of {approximately}{times}10{sup {minus}6} Al atoms/(electron at 1 keV) was established by comparison with a sputtering experiment in the same apparatus. Velocity distributions measured for the desorbed Al species showed some differences in comparison with methoxy velocity data: a slightly lower peak velocity and a significantly less prominent high-velocity component. 10 refs., 4 figs.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5167958
• Report Number(s): ANL/CP-75386; CONF-920462-2; ON: DE92014858
• Resource Relation: Conference: Workshop on desorption induced by electronic transitions, Taos, NM (United States), 1-4 Apr 1992
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
42 ENGINEERING
ALUMINIUM
PHOTOIONIZATION
DESORPTION
ELECTRON-ATOM COLLISIONS
EV RANGE 100-1000
EXCIMER LASERS
HABIT PLANES
MASS SPECTROMETERS
METHOXY RADICALS
PULSED IRRADIATION
SPUTTERING
TIME-OF-FLIGHT METHOD
ALKOXY RADICALS
ATOM COLLISIONS
COLLISIONS
ELECTRON COLLISIONS
ELEMENTS
ENERGY RANGE
EV RANGE
GAS LASERS
IONIZATION
IRRADIATION
LASERS
MEASURING INSTRUMENTS
METALS
RADICALS
SPECTROMETERS
665300* - Interactions Between Beams & Condensed Matter- (1992-)
426002 - Engineering- Lasers & Masers- (1990-)