Surface Structure Analytical Method by Extended Appearance Potential Fine Structure

Research Project

Project/Area Number	60550011
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Applied materials
Research Institution	Tottori University
Principal Investigator	KONISHI Ryosuke Faculty of Engineering, Tottori University, 工学部, 助教授 (00032269)
Co-Investigator(Kenkyū-buntansha)	SASAKURA Hiroshi Faculty of Engineering, Tottori University, 工学部, 教授 (50032264)
Project Period (FY)	1985 – 1986
Project Status	Completed (Fiscal Year 1986)
Budget Amount *help	¥1,900,000 (Direct Cost: ¥1,900,000) Fiscal Year 1986: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1985: ¥1,500,000 (Direct Cost: ¥1,500,000)
Keywords	EAPFS / APS / Cr / Ti / Amorphous TiFe alloy / Surface Structure Analysis / 角運動量
Research Abstract	We measured the EAPFS spectra using a measuring system of the Auger electron appearance potential(AEAPS) spectra, since both could be obtained as a function of the primary electron energy. The fine structure was recorded in the second-derivative mode. A personal computer was used for initially setting the accelarating voltage as well as for averaging the addition of data points in order to improve the signal-to-noise ratio. The data were stored on a floppy disk. As the samples, polycrystalline Cr, evaporated Ti thin film and amorphous TiFe alloy film were used. 1. Polycrystalline Cr: we obtained a nearest-neighbour atomic spacing of 2.53A(1=0), 2.54A(1=1) and 2.54A(1=2), respectively. These values are in good agreement with the bulk values(2.50A). 2. Evaporated Ti thin film: we obtained a nearest-neighbour atomic spacing of 2.93A (1=0),2.93A(1=1) and 2.58A(1=2) by analyzing the fine structure above the <L_2> threshold. On the other hand, the results of 3.29A(1=0), 3.29A(1=1) and 2.97A(1=2) were obtained from the fine structure above the <L_3> threshold. As a nearest-neighbour atomic spacing of bulk Ti is 2.91A, it is considered that the trantition into 1=0 and 1=1 occure prominantly at the <L_1> excitation. The transition to 1=2 is prominant at the <L_3> excitation. 3. Amorphous TiFe alloy film: we obtained a nearest-neighbour atomic spacing of 2.58A (1=0), 2.44A(1=1) and 2.31(1=2), respectively by analyzing the fine structure above the Ti- <L_1> threshold and obtained 2.87A, 2.77A and 2.57A above the Ti- <L_3> threshold. As there are no data about the atomic spacing of amorphous TiFe alloy, we can not decide the prominant level of the final state. But, as the same distribution angular momenta in the final state can be assumed in spite of the differing chemical environment, we can estimate a nearest-neighbour spacing of about 2.5A.