SYNOPSIS
In the present study, 5-MHz and 27-MHz titanium (Ti) quartz crystal microbalance (QCM) sensors were produced by a thin film magnetron that sputtered Ti onto gold-plated quartz. Scanning probe microscope (SPM) analysis and X-ray photoelectron spectroscopy (XPS) analysis were used to characterize the nanostructure of the Ti films. The respective amounts of adsorption of albumin for the 5-MHz and 27-MHz Ti QCM sensors were compared. SPM analysis showed that the surface roughness of the film was slightly increased by the sputtering process. However, it was covered with an almost uniform particle layer. Furthermore, XPS analysis showed that the film consisted mainly of TiO2. The 27-MHz Ti QCM sensor offers an approximately 24-fold increase in sensitivity over 5-MHz Ti QCM, which determines its attractiveness for application in biomolecular sensing with Ti.
Key words: titanium, QCM, magnetron sputtering