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Structural health monitoring is a means for drastically decreasing the maintenance and logistical cost associated with vehicular platforms especially aircraft. A system of small piezoelectric sensors distributed throughout the vehicle will be capable of acting passively or actively to monitor the changes within a structure that presage a component failure, and they will be able to detect and localize all impacts on the structure and evaluate any damage. Piezoelectric thin films were directly integrated with structural titanium utilizing a metal-organic chemical solution approach. The optimum integration strategy yielded a process easily performed without a cleanroom and semiconductor fabrication tools. [ABSTRACT FROM AUTHOR]

Utilizing a BaSrTiO 3 /NiTi hybrid composite thin film design on a silicon substrate we have successfully fabricated, characterized, and optimized a high performance vibration control pedestal for passive damping of die level MEMS components. The thin film fabrication and integration protocols were accomplished via semiconductor industry standard processing methods and procedures. The ferroelectric tetragonal phase of BaSrTiO 3 was deposited by metalorganic solution deposition (MOSD) technique followed by annealing in flowing oxygen. Thin film NiTi was sputter deposited utilizing a TiNi target in an ultrahigh vacuum chamber, followed by in situ vacuum annealing. Comparison of a variety of designs and integration processing protocols demonstrated that the sequential deposition of the BaSrTiO 3 and NiTi thin films, followed by their respective optimized crystallization anneals at 750 and 500°C, achieved successful materials compatible monolithic integration of the composite bi-layer stack with the Si support wafer. The impact of this materials integration technology, based on foundry friendly film deposition techniques and integration procedures, serves to promote wide-scale implementation of vibration control passive damping for a variety of device/die level structures. [ABSTRACT FROM AUTHOR]

Utilizing a co-planar device design we have successfully designed, faricated, characterized, and optimized a high performance Ta 2 O 5 thin film passive uffer layer on Si sustrates, which will allow the integration of Ba 1 - x Sr x TiO 3 (BST) films with large area affordale Si sustrates. This passive uffer layer thin film was faricated via the industry standard metalorganic solution deposition technique. The anneal optimized Ta 2 O 5 ased thin film possessed an enhanced dielectric constant (ε r = 45.6), low dielectric loss (tan δ = 0.006), high film resistivity (ρ = 10 12 Ω -cm at be = 1 MV/cm), excellent temperature staility (temperature coefficient of capacitance of 52 ppm/°C), and excellent ias staility of capacitance (∼⃒ 1.41% at 1 MV/cm). Additionally, the permittivity and dissipation factor exhiited minimal dielectric dispersion with frequency. The dielectric passive uffer layer film was typified by a uniform dense microstructure with minimal defects, and a smooth, nano-scale fine grain, crack/pinhole free surface morphology. Optimization of the integration design configuration was achieved by evaluating two heterostructure processing protocols; (1) a single anneal and (2) a dual anneal process protocol. Our results demonstrated the dual anneal process, to be an excellent method for realizing the successful monolithic integration of BST with affordale Si sustrates. This work also demonstrated that the coefficient of thermal expansion (CTE) mismatch etween the Ta 2 O 5 uffer and BST active thin films in the coplanar device design serves to enhance the dielectric tunaility of the device. The impact of this materials integration technology will promote road scale implementation of affordale On-The-Move (OTM) phased array antenna systems across a variety of advanced communications platforms. [ABSTRACT FROM AUTHOR]