Compact Benchtop Device for Molecular Vapor Deposition of Self-Assembled Monolayers Used in Nanoimprint Lithography

Abstract:
The deposition of functional thin films with thicknesses in the nanometer range is a key method for numerous processes in microsystems technology. In this context, self-assembled monolayers (SAMs) are gaining increasing importance. Surface functionalization with hydrophobizing SAMs, such as perfluorodecyltriethoxysilane (pFDTS), is particularly essential in the nanoimprint lithography (NIL) process. Utilized as anti-sticking coating they enable the transfer of nano structures from an elaborately produced master wafer on a polymer stamp, which is used as tool for the structure transfer. Addressing the crucial process of depositing anti-sticking coatings, this work presents a compact benchtop device for molecular vapor deposition of SAMs on 100 mm and 150 mm substrates. The device offers precise control over key process parameters, including temperature, pressure, and nitrogen conditioning, ensuring reproducible and uniform coatings. A heated gas wash bottle (bubbler) serves as both precursor reservoir and evaporation unit. Successful hydrophobization of silicon surfaces are confirmed by measurements of Young’s contact angle via the sessile drop method, revealing an increase from 56deg to 107deg.