WISOL CO., LTD.

Provided is an electromagnetic wave shielding sheet, a flexible printed circuit board attached with the electromagnetic wave shielding sheet, and a manufacturing method thereof. The flexible printed circuit board attached with the electromagnetic wave shielding sheet comprises: an electromagnetic wave shielding sheet including a nonwoven fabric having a plated surface and including an adhesive layer adsorbed therein without containing conductive particles, and a nonwoven fabric layer including a first insulating layer formed on the nonwoven fabric; and a flexible printed circuit board attached with the electromagnetic wave shielding sheet, wherein the flexible printed circuit board includes: a base film having a wiring pattern and a ground pattern formed on one side; and a second insulating layer covering the wiring pattern and exposing the ground pattern, and the nonwoven fabric layer having the adhesive layer adsorbed therein is in direct contact with the ground pattern.

Disclosed is a surface acoustic wave (SAW) filter having a temperature compensation layer. The SAW filter includes: a series resonator group having a plurality of series-type SAW resonators connected in series; and a parallel resonator group having a plurality of parallel-type SAW resonators connected in parallel. Each of the series-type SAW resonators and the parallel-type SAW resonators comprises a piezoelectric substrate, an interdigital transducer (IDT) electrode formed on the piezoelectric substrate, and a temperature compensation layer covering the IDT electrode. At least one series-type SAW resonator among the series-type SAW resonators has a temperature compensation layer having a layer thickness different from layer thicknesses of temperature compensation layers of other series-type SAW resonators, or at least one parallel-type SAW resonator among the parallel-type SAW resonators has a temperature compensation layer having a layer thickness different from layer thicknesses of temperature compensation layers of other parallel-type SAW resonators.

The present invention relates to an elastic wave device and a method of manufacturing the same, wherein the elastic wave device according to one embodiment comprises: a piezoelectric substrate having a first surface and a second surface; a support substrate having a third surface adjacent or in contact with the first surface to form a cavity defined by a space; a first adhesive layer disposed between the support substrate and the piezoelectric substrate, forming a bonding interface to join the first surface and the third surface; a second adhesive layer formed on at least one of the third surface and the first surface, which are surfaces where the bonding interface is not formed, the second adhesive layer being exposed within the cavity; and an IDT electrode formed on the second surface, and wherein a thickness of the first adhesive layer is greater than that of the second adhesive layer.

The present disclosure relates to an elastic wave device and a method of manufacturing the same. The elastic wave device according to one embodiment comprises: a support substrate having a first surface; a piezoelectric substrate having a second surface adjacent to or in contact with the first surface of the support substrate forming a cavity defined by the space, and a third surface opposite the second surface; a first adhesive layer disposed between the support substrate and the piezoelectric substrate, forming a bonding interface to bond the first surface and the second surface; a second adhesive layer formed on at least one of the first surface and the second surface where the bonding interface is not formed, and exposed within the cavity; and an IDT electrode formed on the third surface, and a thickness of the first adhesive layer is greater than a thickness of the second adhesive layer.

A surface acoustic wave (SAW) device including resonators formed on piezoelectric substrates of different heights and a method for manufacturing the same are provided. The SAW device includes: a support substrate; a piezoelectric substrate disposed on the support substrate and including a first region, a second region, and a step region disposed between the first and second regions; a first resonator formed on the first region of the piezoelectric substrate; a second resonator formed on the second region of the piezoelectric substrate; and a bus bar formed on the step region of the piezoelectric substrate. The piezoelectric substrate has different thicknesses between the first and second regions, and a surface of the step region connecting the first and second regions forms an angle of 60 degrees or less with the top surface of the first or second region.

Disclosed is a surface acoustic wave (SAW) device including a piezoelectric substrate, and an IDT electrode layer formed on the piezoelectric substrate. The IDT electrode layer includes: an adhesive layer for bonding to the piezoelectric substrate; a first electrode diffusion layer formed on the adhesive layer; a first alloy forming layer formed on the first electrode diffusion layer; a main electrode layer formed on the first alloy forming layer; a second alloy forming layer formed on the main electrode layer; a second electrode diffusion layer formed on the second alloy forming layer; and a connection layer formed on the second electrode diffusion layer.

Provided is a method for manufacturing a surface acoustic wave (SAW) device having multiple filter bands according to the present invention comprises: forming a first electrode layer on an upper portion of a substrate; forming a second electrode layer at a position adjacent to a formation position of the first electrode layer on the upper portion of the substrate; forming a wiring defect prevention layer surrounding one end of the first electrode layer and the other end of the second electrode layer; and forming a metal wiring layer on upper portions of the first electrode layer, the second electrode layer, and the wiring defect prevention layer.

A surface acoustic wave device having an electrode structure with improved nonlinearity, a filter including the same, and a method for manufacturing the surface acoustic wave device are provided. The surface acoustic wave device comprises a piezoelectric substrate and a plurality of IDT electrodes formed on the piezoelectric substrate, wherein each of the plurality of IDT electrodes comprises a lower electrode formed on a surface of the piezoelectric substrate and an upper electrode formed on the lower electrode, and wherein the lower electrode has a hardness of 12 GPa to 16 GPa.

A method of manufacturing a bulk acoustic wave (BAW) resonator according to an embodiment of the present invention may include: forming a lower electrode above a substrate; forming a nitrogen layer on an upper surface of the lower electrode through nitrogen (N 2 ) plasma surface treatment; forming a piezoelectric layer made of an AlScN material above the nitrogen layer to align an upper surface of the piezoelectric layer to an N polarity; and forming an upper electrode above the piezoelectric layer aligned to the N polarity.

A surface acoustic wave wafer level package includes a substrate, an interdigital transducer (IDT) formed on the substrate, a sidewall formed on the substrate along a periphery of the IDT, a cover formed above the sidewall and the IDT to form a hollow above the IDT with the sidewall, a connection electrode formed on the substrate and extending outward from a periphery of the sidewall, a connection terminal electrically connected to a part of the connection electrode which extends outward from the periphery of the sidewall, and an organic solderability preservative coating layer formed on at least a top surface of the connection terminal.