Time-of-Flight Secondary Ion Mass Spectrometry Study of Zinc Oxide Micropatterning on Self-Assembled Monolayer Template

Abstract

A micropatterning process for ZnO on self-assembled monolayer (SAM) templates has been investigated with a time-of-flight secondary ion mass spectrometry (TOF-SIMS) technique. A phenyl-trichloro-silane (PTCS) SAM was exposed to UV light through a photomask and the resultant SAM template was catalyzed using colloid. ZnO was deposited on the catalysts in an aqueous solution of zinc nitrate and dimethylamine–borane. Ion distribution in the samples in each intermediate process step was successfully imaged using TOF-SIMS with a beam focused to about in diameter. Organo–silane ions were detected on the PTCS-SAM and their signal intensities decreased with UV-irradiation time, which was consistent with infrared spectroscopy and wetting angle measurements data, revealing that PTCS was modified by UV. Selective adhesion of the catalysts to the non-UV-irradiated SAM regions and the further deposition of ZnO with boron on the catalyzed regions were clearly exhibited by TOF-SIMS. The amount of boron in ZnO estimated from the SIMS results roughly agreed with the chemical analysis data.