H01L41/16

Wet etching of samarium selenium for piezoelectric processing

A subtractive forming method that includes providing a material stack including a samarium and selenium containing layer and an aluminum containing layer in direct contact with the samarium and selenium containing layer. The samarium component of the samarium and selenium containing layer of the exposed portion of the material stack is etched with an etch chemistry comprising citric acid and hydrogen peroxide that is selective to the aluminum containing layer. The hydrogen peroxide reacts with the aluminum containing layer to provide an oxide etch protectant surface on the aluminum containing layer, and the citric acid etches samarium selectively to the oxide etch protectant surface. Thereafter, a remaining selenium component of is removed by elevating a temperature of the selenium component.

METHOD OF TRANSFERRING NANOSTRUCTURES AND DEVICE HAVING THE NANOSTRUCTURES
20190189840 · 2019-06-20 ·

An illustrative method for transferring nanostructures is provided with the steps of: forming a two-dimensional material (2D material) on a first substrate; forming a plurality of nanostructures on the 2D material; bonding a surface of one or more of the plurality of nanostructures with a head or a second substrate, and/or shaking the one or more nanostructures with or without a fluid; and separating the one or more nanostructures from the 2D material.

Impedance matching layer for ultrasonic transducers with metallic protection structure
10326072 · 2019-06-18 · ·

An ultrasonic transducer comprising a piezoelectric element, an acoustic matching layer arranged on a surface of the piezoelectric element and having a thickness of at least one-quarter of a wavelength of a center resonant frequency of the transducer, and a front metal layer arranged on a surface of the acoustic matching layer opposite that of the piezoelectric element and having a thickness equal to one-half of the wavelength of the center resonant frequency.

Magnetoelectric macro fiber composite fabricated using low temperature transient liquid phase bonding
10312429 · 2019-06-04 · ·

A composite material fabricated using a novel process and materials. The piezoelectric and magnetostrictive layers of the composite material are coated, layered, and bonded using a process known as LTTLP bonding. The resulting magnetoelectric composite fibers are bonded to a polyimide film based copper flexible circuit using a room temperature curing epoxy. The sensor that results is an MEMFC that outperforms conventionally fabricated MEMFCs.

Guided wave devices with sensors utilizing embedded electrodes
10305442 · 2019-05-28 · ·

A micro-electrical-mechanical system (MEMS) guided wave device includes a plurality of electrodes arranged below a piezoelectric layer (e.g., either embedded in a slow wave propagation layer or supported by a suspended portion of the piezoelectric layer) and configured for transduction of a lateral acoustic wave in the piezoelectric layer. The piezoelectric layer permits one or more additions or modifications to be made thereto, such as trimming (thinning) of selective areas, addition of loading materials, sandwiching of piezoelectric layer regions between electrodes to yield capacitive elements or non-linear elastic convolvers, addition of sensing materials, and addition of functional layers providing mixed domain signal processing utility.

Bender bar transducer with at least three resonance modes

A bender bar acoustic transducer capable of exciting at least three resonance modes is provided. The provided bender bar acoustic transducer may be capable of exciting a second resonance mode by configuring a first portion of a piezoelectric element to contract while a second portion of the piezoelectric element expands when voltage is applied to electrodes coupled to the piezoelectric element. The bender bar acoustic transducer may be further configured such that the first portion and the second portion of the piezoelectric element both contract and/or expand to excite a first resonance mode. The bender bar acoustic transducer may be used in downhole and well logging applications.

Wet etching of samarium selenium for piezoelectric processing

A subtractive forming method that includes providing a material stack including a samarium and selenium containing layer and an aluminum containing layer in direct contact with the samarium and selenium containing layer. The samarium component of the samarium and selenium containing layer of the exposed portion of the material stack is etched with an etch chemistry comprising citric acid and hydrogen peroxide that is selective to the aluminum containing layer. The hydrogen peroxide reacts with the aluminum containing layer to provide an oxide etch protectant surface on the aluminum containing layer, and the citric acid etches samarium selectively to the oxide etch protectant surface. Thereafter, a remaining selenium component of is removed by elevating a temperature of the selenium component.

Low-temperature co-firing of multilayer textured piezoelectric ceramics with inner electrodes

Textured PMN-PZT fabricated by templated grain growth (TGG) method has a piezoelectric coefficient (d) of 3 to 5 times that of its random counterpart. By combining this TGG method with low-temperature co-firing ceramics (LTCC) techniques, co-fired multilayer textured piezoelectric ceramic materials with inner electrodes were produced at a temperature as low as 925 C., which silver could be used. Trilayer PMN-PZT ceramics prepared by this method show a strain increase of 2.5 times, a driving voltage decrease of 3 times, and an equivalent piezoelectric coefficient (d*) improvement of 10 to 15 times that of conventional random ceramic counterparts. Further, a co-fired magnetostrictive/piezoelectric/magnetostrictive laminate structure with silver inner electrode was also synthesized. The integration of textured piezoelectric microstructure with the cost-effective low-temperature co-fired layered structure achieves strong magnetoelectric coupling. These new materials have promising applications including as actuators, ultrasonic transducers, and use in energy harvesters.

Display device and laminated optical film

Provided is a display device containing a crystalline piezoelectric polymer layer having a helical chiral polymer (A) that has a weight average molecular weight of from 50,000 to 1,000,000 and has optical activity, an optical compensation layer satisfying the following expression (1), and a linear polarizer. In expression (1), Xc represents a degree of crystallinity (%) of the crystalline piezoelectric polymer layer obtained by a DSC method; MORc represents a standardized molecular orientation of the crystalline piezoelectric polymer layer measured by a microwave transmission molecular orientation meter when a reference thickness is 50 ?m; d represents a thickness (?m) of the crystalline piezoelectric polymer layer; and Rth represents a phase difference (nm) in a thickness direction of the optical compensation layer at a wavelength of 550 nm.
|0.06?Xc?MORc?d+Rth|?500Expression (1):

FILM BULK ACOUSTIC RESONATOR AND METHOD OF MANUFACTURING THE SAME

A film bulk acoustic resonator includes: a first electrode disposed on a substrate; a piezoelectric body disposed on the first electrode and including AlN to which a dopant is added; and a second electrode disposed on the piezoelectric body and facing the first electrode such that the piezoelectric body is interposed between the second electrode and the first electrode, wherein the dopant includes either one of 0.1 to 24 at % of Ta and 0.1 to 23 at % of Nb.