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ABSTRACT:The infrared and Raman spectra of trichloro cyclohexylsilane has been recorded. Density functional theory, DFT, with the different functional groups was used for the optimization of the ground state geometry and simulation of the Infrared and Raman spectra of this molecule. Calculated geometrical parameters fit very well with the experimental ones. The Self Assembled Monolayer of trichloro cyclohexylsilane on Si/SiO 2 substrate was prepared and the resulting surface was studied using Atomic Force Microscopy (AFM). KEYWORDS: Self assembly, Monolayers, Atomic Force Microscopy I.INTRODUCTIONFormation of SAM, provides one of the easiest ways to obtain ordered monolayers through strong chemisorption between the substrate and the molecule [1].Silanes are used as coupling agents to adhere fibres such as glass fibres and carbon fibres to certain polymer matrices,stabilizing the composite material.The silyl derivatives are of growing interest in the field of molecular electronics,for their ability to form well defined self assembled molecular thin films with predefined functions [9].Hence in this work we have characterized the silyl head group using FTIR and FT Raman Spectroscopy aided by DFT computed molecular parameters. II. MATERIALS AND METHODS Sample preparation and formation of SAMThe AR grade Trichlorocyclo hexyl silane (TCCHS) was purchased commercially from Sigma Aldrich and was used as received. The solvent toluene and other inorganic chemicals of GR grade were obtained from Merck. The spin coating technique is used for preparation of SAMs in this experiment, as an interesting alternative to the more common method of submerging the substrate in a silane solution [2].Four inch diameter silicon wafers with a native oxide layer(p-type, h100i orientation, 20-30 X cm resistivity and surface roughness .19 nm) were cut into samples of 1 cmby 1 cm and then, the substrates were first sonicated for 10 min in propanol, acetone and ultrapure water (Millipore Direct-Q,18 MX-cm resistivity). It was then cleaned with piranha solution (3:1 volumetric ratio H 2 SO 4 /H 2 O 2 ) for few minutes or until the visible reaction stops,taking extreme caution while using very strong oxidant piranha solution, due to its violent reactivity towards organic matter. The silicon wafers were again rinsed with ultrapure water and dried under N 2 gas.The TCCHS was diluted with toluene, [2, 3] to form 0.01 M, 0.05 M, and 0.1 M solutions. It was found that the solution concentration played a vital role in the formation of SAM of silane.since at lower concentrations, it was found to form incomplete island like structures and higher concentrations favored multi layers formation. A smooth monolayer was formed at 0.001 M concentration by spin coating technique. The monolayer formation was optimized with different speeds and a speed of 5000 rpm yielded best result. The spin coating was performed under the anhydrous conditions of a glove box . Later, the substrates were exposed to ammonia and hydrochloric acid vapors for a few hours at room tem...