標題: | Adsorption and decomposition studies of t-butylamine, diethylamine, and methylethylamine on Si(100)-(2 x 1) |
作者: | Wu, JB Yang, YW Lin, YF Chiu, HT 應用化學系 Department of Applied Chemistry |
公開日期: | 5-二月-2004 |
摘要: | We have studied chemisorption and thermal decomposition of tert-butylamine (TBA), diethylamine (DEA), and methylethylamine (MEA) on Si(100)-(2 x 1) with synchrotron-based X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD). Adsorption at cryogenic temperature leads to molecularly intact chemisorption (dative-bonding via the nitrogen lone pair) and dissociative chemisorption via N-H scission, producing distinct N 1s peaks at binding energies of 401.1 and 398.2 eV, respectively. The corresponding change for C 1s core level is also significant, and a 0.9 eV shift toward lower binding energy is found for DEA, suggesting a high degree of charge redistribution between two adsorption configurations. Upon warming to room temperature, the adsorbed amines almost completely transform into dissociative chemisorbed forms. Thermal decomposition of TBA at elevated temperatures produces desorption species of isobutylene via gamma-H elimination, hydrogen cyanide, and H-2. In comparison, DEA and MEA decompose thermally to desorb imine via P-H elimination, ethylene via beta-H elimination, hydrogen cyanide, and H2. Eventually, silicon nitride and silicon carbide are formed. Distinct decomposition pathways lead to a C/N ratio variation among the products, with TBA yielding the lowest C/N ratio. |
URI: | http://hdl.handle.net/11536/27041 |
ISSN: | 1520-6106 |
期刊: | JOURNAL OF PHYSICAL CHEMISTRY B |
Volume: | 108 |
Issue: | 5 |
起始頁: | 1677 |
結束頁: | 1685 |
顯示於類別: | 期刊論文 |