Surface modeling of thin film growth: A study of silicon oxide deposition from tetraethoxysilane and silicon deposition from disilane on the Si(100) surface

Miscellaneous · Fri Jan 01 00:00:00 EST 1993

OSTI ID:7114711

Cho, Hee-Chuen

In this thesis, surface reactions brought about by the pyrolysis of adsorbed TEOS, the modeling of this reaction with ethanol, and the photolysis of adsorbed disilane have been investigated under ultrahigh vacuum conditions, using mainly temperature programmed desorption (TPD). TEOS molecularly desorbs at about 195K when adsorbed on clean Si(100) at low temperatures. When adsorbed at 300K, the primary surface species produced is a mixture of ethoxysiloxanes. Upon heating the surface in vacuum, the adsorbed ethoxysiloxanes decompose the evolve ethylene and hydrogen, with trace production of acetylene and acetaldehyde. In a parallel study, the adsorption and subsequent deposition of ethanol (C[sub 2]H[sub 5]OH, C[sub 2]D[sub 5]OD, and CH[sub 3]CD[sub 2]OH) on Si(100) has been shown to model the TEOS system. The molecular desorption temperature is ca. 150K. When adsorbed at 200K, ethanol dissociatively chemisorbs as an ethoxide and the monohydride species. The adlayer decomposes at higher temperature to evolve ethylene, hydrogen, acetaldehyde, and acetylene. The adsorption and decomposition of ethanol on Si(100)-2x1:H has also been studied in gathering additional information about the competition between distinct decomposition mechanisms, and the nature of the reaction site. In the Si[sub 2]H[sub 6]/Si(100) system, with no UV irradiation, disilane adsorption at 120K produces a chemisorbed SiH[sub x] (x = 1 - 3) layer and, for high exposures, a disilane multilayer. Upon heating the surface in vacuum, molecular desorption is observed at ca. 150K, while hydrogen and silane are evolved at much higher temperatures. For Si[sub 2]H[sub 6] exposure during photo-irradiation, the desorption yields of hydrogen and silane are enhanced. Model studies using the partially and fully deuterated Si(100)-2x1:D surface reveals that the photo-induced surface reaction is dominated by an insertion reaction by the photo-generated silylene species.

• Research Organization: California Univ., San Diego, La Jolla, CA (United States)
• OSTI ID: 7114711
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
SILANES
PHOTOLYSIS
SORPTIVE PROPERTIES
SILICON OXIDES
CHEMICAL VAPOR DEPOSITION
VAPOR PHASE EPITAXY
CHEMICAL REACTIONS
DECOMPOSITION
ETHANOL
TEMPERATURE DEPENDENCE
THIN FILMS
ALCOHOLS
CHALCOGENIDES
CHEMICAL COATING
DEPOSITION
EPITAXY
FILMS
HYDRIDES
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
SILICON COMPOUNDS
SURFACE COATING
SURFACE PROPERTIES
360601* - Other Materials- Preparation & Manufacture
400201 - Chemical & Physicochemical Properties