1991 Fiscal Year Final Research Report Summary
Lazer spectroscopic study on vibrutional excitation of NO on alkalated Si surfaces.
| Project/Area Number |
02640339
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
物理化学一般
|
|---|
| Research Institution | Toyohashi University of Technology |
|---|
Principal Investigator |
NAMIKI Akira Toyohashi University of Technology Department of Engineering (Associate Professor), 工学部, 助教授 (40126941)
|
|---|
| Project Period (FY) |
1990 – 1991
|
| Keywords | REMPI / Electron Transfer / Alkali-Promotion / Molecular Beam / 電子移動 |
|---|
| Research Abstract |
Alkali-metal (K and Cs adatoms) promotion of NO sticking on Si (100) has been studied using a molecular beam method combined with AES and REMPI detection. The observed sticking probability S shows a good correlation with rheta_<alkali>, indicating that the alkali promotion is local in nature. The decay of S as a function of NO dose as observed with AES shows an anti-correlation with the evolution of the direct-inelastic scattering intensity as obtained with REMPI. This fact is understood as follows : since the direct-inelastic scattering occurs mostly in a single collision process with the surface, local alkali promotion is realized in a single collision of the incident NO molecule with the alkali-metal adsorbates. The decay of S as a function of NO dose is then simulated by introducing a reaction cross section. The evaluated reaction radii are almost eaual to but somewhat larger than the covalent radius of a K atom, with a increasing trend with rheta_K. The alkali promotion is explained in terms of electron charge transfer from the non-ionized alkali adatoms to the affinity level of NO molecules based on the adatom density of state around E_F.
|
