8:00 PM - FF04.05.27
Characterization of Flash Lamp Cured, Sol-Gel Derived Tantalum Oxide Films
Christopher Beale1,Stefanie Hamacher1,Oumaima Bensaid1,Alexey Yakushenko2,Dirk Mayer1,Bernhard Wolfrum1,3,Andreas Offenhäusser1
Forschungszentrum Jülich GmbH1,is it fresh GmbH2,Technische Universität München3
Prior attempts at reducing the crystallization temperature of metal oxide films have succeeded via chemical solution deposition and photochemical solution deposition . These methods include seeding solutions with crystalline nanoparticles in order to reduce the activation barrier for nucleation and crystal growth, or incorporating photosensitive compounds into the solution and thereby reducing the crystallization temperature during exposure to continuous UV irradiation. In one study, a xenon flash lamp was utilized to obtain nanocrystalline thin films by the use of a metal β-diketonate solution . Thus, the aim of this study is to determine whether such solutions can be used to obtain tantalum oxide films with a xenon flash lamp, and how future studies could allow for crystallization from the amorphous state via pulsed laser irradiation, or from the solution state via seeding or the incorporation of photosensitive tantalum complexes .
In this investigation, the characteristics of a photosensitive, tantalum β-diketonate sol-gel ink were studied as a function of flashes from a xenon flash lamp at room temperature. The ink was printed on quartz substrates for UV-Vis spectrophotometry in order to follow the absorption versus flash lamp exposure, and on interdigitated electrodes in order to follow the capacitance versus flash lamp exposure. The results indicate that the UV-Vis absorption spectrum is similar to those found for tantalum oxide films obtained by photo-irradiation , , and the interdigitated electrode capacitance increases with the number of xenon flash lamp flashes. An increase in capacitance hints at oxide densification and formation , thus allowing for a photopatternable material. The amorphous film could be subsequently heat treated to achieve polycrystalline films , or exposed to pulsed laser irradiation to similarly achieve high temperatures . The photosensitivity of the ink also allows for future investigations involving low temperature crystallization via photochemical solution deposition, as has been performed for lead-titanate based precursors, among others . Moreover, the air stable solution would further increase the ease of manufacturing and allow for it to be implemented into a roll-to-roll manufacturing line .
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