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Multifunctional ToF-SIMS: Combinatorial Mapping of Gradient Energy Substrates



S V. Roberson, Albert J. Fahey, A Sehgal, Alamgir Karim


We present a simple method for chemical modification of chlorosilane self-assembled monolayers (SAMS) on Si surfaces by exposure to a gradient of UV-ozone radiation to create stable substrates with a range of contact angles (θ H2O {approximately equal to} 5{degrees C} - 95{degrees C}) and surface energies on a single substrate. These gradient energy substrates are developed to potentially generate libraries for combinatorial studies of thin film phenomenology. The graded oxidation process presents a systematic variation of surface chemical composition. We have utilized contact angle measurements and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to investigate this variation for a series of ions, among which are SiCH3+, SiOH+ and COOH-. We show that the macroscopic measurements of surface free energy/contact angle correlate with the detailed analysis of surface chemistry (as assessed by TOF-SIMS) on these test substrates.
Applied Surface Science
No. 1-4


surface energy gradient, ToF-SIMS, UV-ozone treatment


Roberson, S. , Fahey, A. , Sehgal, A. and Karim, A. (2002), Multifunctional ToF-SIMS: Combinatorial Mapping of Gradient Energy Substrates, Applied Surface Science (Accessed September 21, 2023)
Created November 1, 2002, Updated February 17, 2017