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As the number of passive components in electronic circuits increases, new methods for fabricating passives are under development to optimize utilization of board space. In this paper, we will describe the performance capabilities of TPL's micro‐contact printing (μCP) process to fabricate near‐net‐shape structures with feature sizes ranging from 100 microns to the sub‐micron scale. Like thick film processes, this novel process is compatible with a broad materials base, making a large range of materials properties available. Unlike thick film, however, this novel process employs powder‐free inks that can be patterned with high resolution. It is anticipated that this process will enable integration of passive components that show thin film performance at thick film cost. Emphasis in this paper will be placed on processing conditions, and materials properties to demonstrate the feasibility of this process for passive device fabrication.

The development of stress in the SrBi2Ta2O9 (SBT) films generated from a chemical solution deposition method was monitored during processing using wafer curvature measurements. Stress measurements of the entire Si/SiO2/Pt/SBT stack revealed an overall tensile stress of ∼536 MPa. The greatest increase in tensile stress was recorded for the anneal of the Pt bottom electrode and was due to the thermal expansion mismatch. Deposition of an amorphous SBT layer on the Pt, followed by a low temperature anneal (300°C), had little overall effect on the stress of the stack; however, upon crystallization, significantly more tensile stress was introduced into the stack. To further investigate the effect that stress has on the various electrical properties SBT films, wafers with different stress states were produced and SBT films deposited on them. Initial investigations indicate that SBT films on wafers with a higher tensile stress displayed improved ferroelectric hysteresis and switchable polarization.

The growth of epitaxial thin films of Li1–xNb1–xWxO3 from solution precursors on single-crystal LiNbO3 substrates is reported. An all-alkoxide solution readily gave single phase powders after simply mixing the constituent components, whereas an acetate-alkoxide system required additional solution processing stages to give phase pure powders. Heat treatment of films on single-crystal, basal plane LiNbO3 substrates at 600 °C formed a nanocrystalline, porous film which was converted to an epitaxial film after heating to 800 °C. Measurements of second harmonic generation in powders indicate an increase in SHG efficiency with increasing tungsten content. Optical absorption data for films were calculated using reflectance and transmittance spectroscopy data, and indicate a decrease in bandgap with increasing tungsten.

SrBi2Ta2O9 (SBT) films have received considerable attention for use as nonvolatile memory elements. We have developed a process to prepare SBT films with good ferroelectric properties at low temperatures. In this paper, we will present strategies used to optimize the properties of the films including film composition, the nature of the substrate (or bottom electrode) used, and the thermal processing cycle. Under appropriate conditions, ∼1700A films can be prepared which have a large switchable polarization (2Psw >10μC/cm2), and an operating voltage ≤2.0V.

A solution precursor method based on metal alkoxides was used to produce epitaxial LiNbO3 thin films, ≈200 nm thick, on (0001) sapphire substrates. Transmission electron. microscopy revealed that the major cause of surface roughness in these films was grain boundary grooves between mosaic grains with misorientations ≤5°. It is postulated that these low angle boundaries directly result in surface grooving and roughness. The epitaxial films also contained two distinguishable variants in the film/substrate interfacial plane, namely, an aligned variant, and a 60° rotated variant, . A seeded grain growth method was used to minimize the presence of the 60° rotated variant. An epitaxial buffer layer of Fe2O3 was used to lower the mismatch strain, eliminate the 60° rotated variant, and reduce the mosaic nature of the LiNbO3 film. X-ray rocking curve full-width-at-half-maximum (FWHM) values measured on the film peak indicate that the mosaic character can be reduced from 1.5° to 0.76° by using a buffer layer.

The electromechanical properties of sol-gel derived ferroelectric Pb(Zro.53Tio.47)O3 (PZT 53/47) thin layers deposited on silicon were determined as a function of fieldstrength, measurement frequency and total thickness. Both electrically-induced strains (e) and piezoelectric properties (d33) were characterized by interferometry. Dielectric spectroscopy and polarization switching (P-E) measurements were determined for comparative purposes. An asymmetry between forward and the reverse bias conditions in the e-E displacements was found for both 5-layer deposited and 9-layer deposited structures. However, no asymmetry was observed in the P-E hysteresis characteristics. In addition, the electrically-induced strains and the piezoelectric response were found to be dependent on measurement frequency. No significant frequency dependence was observed in the polarization or dielectric responses. The results are discussed in terms of a possible clamping effect for polarization switching.

The electromechanical properties of sol-gel-derived ferroelectric Pb(Zr0.53Ti0.47)O3 (PZT 53/47) thin layers deposited on silicon were determined as a function of field strength, measurement frequency, and total thickness. Both electrically induced strains (∊) and piezoelectric properties (d33) were characterized by interferometry. Dielectric spectroscopy and polarization switching (P-E) measurements were determined for comparative purposes. An asymmetry between forward and the reverse bias conditions in the ∊-E displacements was found for both five-layer deposited and nine-layer deposited structures. However, no asymmetry was observed in the P-E hysteresis characteristics. In addition, the electrically induced strains and the piezoelectric response were found to be dependent on measurement frequency. No significant frequency dependence was observed in the polarization or dielectric responses. The results are discussed in terms of a possible clamping effect on polarization switching.

A review is given of the sol-gel processing of electrical and magnetic ceramics. Materials include, SnO2,In2O3, WO3, V2O5, VO2, ZrO2, ZnO, BaTiO3, YBa2Cu3O7−δ, Al2O3, 2MgO · 2Al2O3 · 5SiO2, SiO2. 3Al2O3 · 2SiO2, PbTiO3, Pb(Zr,Ti)O3, (Pb, La)(Zr,Ti)O3, LiNbO3, Pb(Mg 1 3 Nb 2 3 )O3, Pb(Zn 1 3 Nb 2 3 )O3, Pb(Sc 1 2 Ta 1 2 )O3, Fe2O3, (Bi,Y)3Fe5O12, and BaFe12O19. Details are reported for the synthesis routes and the fabrication of ceramic components, including conductors, resistors and insulators, and includes, electronic and ionic properties, varistors, thermistors, superconductors, dielectrics, ferroelectrics, magnetics, and microelectronic materials.

The properties of thin layer ferroelectrics appear to differ, sometimes considerably. from those of bulk ceramics of the same composition. Most notably, a broadening of the temperature dependent dielectric anomaly, an increase in the coercive field and a decrease in the remnant polarization are frequently reported. Recent advances in processing thin layers by chemical methods, and in sol-gel processing in particular, have resulted in the capability of fabricating thin layer fermelectrics in which variations in phase composition and microstructure can be. controlled and minimized. In this work. single phase perovskite thin layers of lead zirconate. titanate (PZT) with a composition near the morphotropic phase boundary (Zr/Ti = 53/47) were deposited onto platinized silicon substrates by spin-casting pre-hydrolyzed alkoxide solutions. Ferroelectric and dielectric properties are reported as a function of layer thickness and discussed in terms of an interface effect, series impedance model, and the ac...

Acrylic (PAN) fibers with a novel coiled morphology as precursors for semiconducting carbon IR detection elements were prepared using a “hybrid” spinning technique combining principles from standard wet and dry spinning methods. Fiber structure and morphology were found to depend on furnace temperature and coagulation conditions. The highest-density fibers were formed at a furnace temperature of 180°C and a coagulation bath composition of H 2 O:DMF = 3:1 at 19°C. Fibers with diameters of 100–200 μm were obtained, which when fired had resistivities in the range ≈ 3–70 Ω cm, and thermistor constants of B ≈ 1300–2500 K. Their application as IR detection elements is reported.

The evolution of structure and chemical distribution in sol-gel derived Pb(Zr0.53T10.47)O3 thin layers was monitored by x-ray diffraction, analytical electron microscopy, and diffuse reflectance Fourier transform infrared spectroscopy. Electron microscopy confirmed the as-deposited coatings were amorphous with short-range order. Medium-range order developed on heat treatment, and chemical heterogeneity was observed at the nanoscale. The extent of compositional heterogeneity decreased with increasing temperature. Above 500 °C, the coatings crystallized into an intermediate phase which converted to the perovskite phase above 600 °C.