| Abstract
| - Field-emission electron microscopy (FE-SEM) was applied to observe coplanar microstructures composed oftwo different types of organosilane self-assembled monolayers (SAMs). These binary microstructures wereprepared on silicon substrates covered with native oxide by a lithographic technique. Four types of organosilaneprecursors, they are n-octadecyltrimethoxysilane (ODS), heptadecafluoro-1,1,2,2-tetrahydro-decyl-1-trimethoxysilane (a type of fluoroalkylsilane, FAS), n-(6-aminohexyl)aminopropyltrimethoxysilane (AHAPS), and4-(chloromethyl)phenyltrimethoxysilane (CMPhS), were used in this study. Micropatterns composed of theSAMs were clearly imaged by FE-SEM at low acceleration voltages, around 0.6 kV. The brightness order ofthe SAMs in FE-SEM was ODS > AHAPS > CMPhS > FAS. Through ab initio molecular orbital calculations,the origin of this FE-SEM contrast was ascribed to the electron affinity between the SAMs, which governedthe FE-SEM image contrast. It has been successfully demonstrated that FE-SEM could provide us chemicalinformation on organic films with a monomolecular thickness on a solid support.
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