Publication Date:
2015-03-31
Description:
The effects of chemistry, substrate, and processing conditions on through-thickness cation distributions are explored in solution-derived morphotropic composition lead zirconate titanate (PZT) films. Films prepared from chelate-based and conventional sol–gel chemistries were spin cast onto Pt/ZnO/SiO 2 /Si and Pt/Ti/SiO 2 /Si substrates and pyrolyzed at 300°C, 350°C, and 400°C prior to crystallization at 700°C either in a preheated furnace or via rapid thermal processing. For films crystallized within a conventional furnace on Pt/ZnO/SiO 2 /Si substrates no chemical gradients were observed. All films prepared on Pt/Ti/SiO 2 /Si substrates had increased titanium concentrations near the PZT/Pt interfaces, and the source is shown to be titanium diffusing from the substrate metallization stack. The effect of heating method and rate was explored in films prepared on Pt/ZnO/SiO 2 /Si substrates with 15°C, 50°C, and 100°C/s heating rates within a rapid thermal annealer. Only one solution chemistry-heating rate combination resulted in the formation of a chemical gradient: a conventional sol–gel chemistry and a 50°C/s heating rate. Infrared spectroscopy of pyrolyzed gel films showed absorption spectra differences in the bonding structure between the two chemistries with the conventional sol–gel-derived films exhibiting a signature more similar to that of a PbTiO 3 gel, suggestive of a gel-structure source of gradient formation during crystallization.
Print ISSN:
0002-7820
Electronic ISSN:
1551-2916
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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