Hydrogen vibrations on Si (111)

The structures of physisorbed and chemisorbed formic acid on Si(111)-7×7

“…The peak at 680 cm À1 is assigned to the stretching mode of Si-O, similar to the m Si-O feature in the reaction of methanol with Si(1 1 1)-7 · 7 [42]. The appearance of spectrum intensity of Si-H around 2000-2150 cm À1 indicates the dissociative chemisorption nature of formic acid on Si(1 1 1)-7 · 7 [43]. For the chemisorbed HCOOD, the new peak at 1540 cm À1 is ascribed to the stretching mode of Si-D, which agrees well with the vibrational feature of the Si-D stretching mode at 1520 cm À1 when CD 3 CD 2 OD is dissociatively reacted with the Si(1 0 0) surface [44].…”

Scanning tunnelling microscopy of the interaction of hydrogen with silicon surfaces

“…Despite this effort, many of these earlier studies yielded LEED studies showed either no change in the 7 x 7 pattern following adsorption [47] or either a partial or complete loss of the seven-by periodicity [40,44,[48][49][50]. Early infrared and EELS studies showed the presence of both monohydride and dihydride species on the saturated surface [41,44,45]. Higher resolution studies Figure 3.…”

“…Early investigations of this system involved LEED [30,31,40] structural studies and both infrared [41][42][43] and electron energy loss spectroscopy (EELS) studies [30,44,45] to determine the nature of the binding sites and the types of hydride species produced on adsorption. Photoemission spectroscopy (PES) has also been employed to observe the quenching of surface states and the development of hydrogen related features [30,40,46].…”

Hydrogen Transfer on Metal Surfaces

“…can therefore easily be chemically eroded by exposure to hydrogen, especially at elevated temperatures, despite the large activation barrier for spontaneous H 2 dissociation [30]. Similar effects have been reported for semiconductor surfaces (Si, Ge, GaAs), which can undergo successive hydrogenation and form volatile hydrides, i.e., SiH 4 (silane), GeH 4 (germane), GaH 3 (gallane) and AsH 3 (arsine), as soon as reactive H atoms are available at the surface [31,32].…”