Surface chemistry on silicon(100)
Surface chemistry on Si(100) has been investigated by employing several surface science methods. Three classes of experimental studies, including: (1) hydrocarbon surface chemistry, (2) adsorbate bonding structures, and (3) H-induced surface restructuring and reactions, are presented. The importance of the surface dangling bonds in the adsorption and reaction of adsorbates on Si(100) is demonstrated in the first two classes of studies. In the third one, reactions as well as restructuring of the Si(100) surface, induced by atomic hydrogen, are investigated. The interaction of various hydrocarbon species, including C[sub 2]H[sub 2], C[sub 2]H[sub 4], and the adsorbed methyl group, with the Si(100) surface has been studied. Absolute coverage measurements show that the coverages for both C[sub 2]H[sub 2] and C[sub 2]H[sub 4] on Si(100) reach monolayer saturation where the stoichiometry is believed to be 1 molecule for 1 Si[sub 2] dimer site. The majority (>95%) of the chemisorbed C[sub 2]H[sub 2] undergoes dehydrogenation by heating. In contrast, the low activation energy for desorption (E[sub d[sup o]] (C[sub 2]H[sub 4]) = 38 kcal/mol) allows C[sub 2]H[sub 4] to desorb prior to significant decomposition. In addition, studies of the thermal behavior of the adsorbed methyl group indicate that the methyl group is stable up to [approximately]600 K before decomposition. The role of atomic hydrogen on the structure as well as the surface chemistry of Si(100) has been investigated. Atomic hydrogen is found to initiate surface chemistry via pathways not accessible by thermally accommodated adsorbates. The investigations of this reaction with two types of adsorbates, the halogen and the methyl group, have been carried out. Futhermore, surface restructuring on Si(100) induced by chemisorption of atomic hydrogen is also observed.
- Research Organization:
- Pittsburgh Univ., PA (United States)
- OSTI ID:
- 7243080
- Resource Relation:
- Other Information: Thesis (Ph.D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ETHYLENE
ADSORPTION
CHEMICAL REACTION KINETICS
HYDROGEN
METHANE
SILICON
SORPTIVE PROPERTIES
ALKANES
ALKENES
ELEMENTS
HYDROCARBONS
KINETICS
NONMETALS
ORGANIC COMPOUNDS
REACTION KINETICS
SEMIMETALS
SORPTION
SURFACE PROPERTIES
400201* - Chemical & Physicochemical Properties