Vapor-Phase Deposited Chlorosilane-Based Self-Assembled Monolayers on Various Substrates for Thermal Stability Analysis

Chlorosilane-based self-assembled monolayers (SAMs), including octyltrichlorosilane (C8-OTS), (tridecafluoro-1,1,2,2-tetrahydrooctyl) trichlorosilane (POTS) and dimethyldichlorosilane (DDMS), are applied on various substrates via a vapor-phase coating process for thermal stability analysis. Si(100) wafer dies and commercial vapor phase -deposited nanoparticle films are utilized as substrates to characterize the thermal stability enhancement. Atomic-force microscopy data prove that the vapor-based deposition technique results in a smooth surface with few aggregates. Contact angle goniometry data show that DDMS-based SAMs function effectively as the final protection layer for various substrates and these results are confirmed by thermogravimetric analysis of SAMs on the fumed silica supports. Quantitative analysis from X-ray photoelectron spectroscopy data shows that polymerized DDMS may exist on various surfaces and can contribute to the stable silane structures for DDMS. These test results yield improved understanding of thermal behavior of chlorosilane SAMs under high temperature and indicate that DDMS films are viable options for devices requiring low adhesion and high thermal stability.