Combinatorial synthesis and high throughput evaluation of ferroelectric/dielectric thin-film libraries for microwave applications

Abstract

A library of 256 differently doped thin films of (BaxSr1−x)TiO3 (where 0.5<x<1.0) was generated on a 1 in.×1 in. LaAlO3 substrate using multistep thin-film deposition techniques together with a quaternary masking strategy. Appropriate postannealing processing afforded high-quality epitaxial thin films. The microwave properties, i.e., dielectric constant and loss tangent, of samples in the library were characterized with a scanning-tip microwave near-field microscope at 1 GHz, and the results were found to be consistent with measurements made with interdigital electrodes. Specific dopants were found to significantly affect the dielectric constant and tangent loss. Tungsten, in particular, reduces the tangent loss.

Catalysis Research of Relevance to Carbon Management: Progress, Challenges, and Opportunities

“…Similar techniques are just beginning to be used in catalytic science, for example, the generation of transition-metal ligands for homogeneous catalysis. 223 In addition to application of combinatorial approaches to catalyst design, these techniques have been used to design materials with improved magnetic, 224 ferroelectric, 225 and optical 226 properties (e.g., phosphors for advanced display technologies). It has been possible to develop spatially addressable arrays of thin films offering artificial lattices, epitaxial overlayers, and unique patterning.…”

Interaction of ambient nitrogen gas and laser ablated carbon plume: Formation of CN

“…Among the several characteristics that distinguish PLD from other film growth techniques is congruent deposition, and hence it has been used to grow superconducting superlattices and superconducting device structures [8]. Recently, combinatorial methods, an approach in which a large number of materials are synthesized, processed and screened Nuclear Instruments and Methods in Physics Research B 192 (2002) [301][302][303][304][305][306][307][308][309][310] www.elsevier.com/locate/nimb for specific properties have been applied to the discovery and optimization of several functional materials [9,10].…”

Direct mapping of the electric permittivity of heterogeneous non-planar thin films at gigahertz frequencies by scanning microwave microscopy

“…21 In spite of the large number of successful applications of the SMM, a main challenge still remains, namely, the difficulty in mapping the electric permittivity of heterogeneous samples exhibiting large height variations. Until now, most applications have dealt with either heterogeneous 2D planar samples 6,12,22,23 or with homogeneous 3D samples, 24 but they have not addressed the general situation of 3D heterogeneous systems, yet. The emergence of the new 3D electron device technologies (e.g.…”

“…9 for a thorough review). Examples of application of the SMM includes the rapid, non-destructive and local detection of the electric permittivity in insulating materials, ferroelectric and new functional materials discovered by combinatorial synthesis, 10,11,12 which are employed in supercapacitors, batteries, non-volatile memories, diodes and photovoltaic cells. This type of SMM applications are expected to contribute also to the field of new nanomaterials for microwave applications (e.g.…”