Murata Manufacturing Co., Ltd.

Mari Saji

Atsushi Kurokawa

Hajime Kando

Hideki Iwamoto

Junpei Yasuda

Masahiro Shibata

Tetsuya Kimura

Ryo Nakagawa

Koshi Himeda

Hiroaki Tokuya

Yasuyuki Ida

An elastic wave device includes a piezoelectric substrate mainly including lithium niobate, an interdigital transducer electrode provided on the piezoelectric substrate, and a dielectric film, provided on the piezoelectric substrate and covering the interdigital transducer electrode, and mainly including silicon oxide. The elastic wave device uses a Rayleigh wave. The interdigital transducer electrode includes main electrode layers that include one or more first main electrode layer made of a metal with a C11/C12 ratio greater than the C11/C12 ratio of the silicon oxide with regard to the elastic constants C11 and C12. The sum of the thicknesses of the one or more first main electrode layers is about 55% or more based on the thickness of the whole interdigital transducer electrode is about 100%.

Elastic wave device

A mesa portion is formed on a substrate. An insulating film including an organic layer is disposed on the mesa portion. A conductor film is disposed on the insulating film. A cavity provided in the organic layer has side surfaces extending in a first direction. A shorter distance out of distances in a second direction perpendicular to the first direction from the mesa portion to the side surfaces of the cavity in plan view is defined as a first distance. A shorter distance out of distances in the first direction from the mesa portion to side surfaces of the cavity in plan view is defined as a second distance. A height of a first step of the mesa portion is defined as a first height. At least one of the first distance and the second distance is greater than or equal to the first height.

Semiconductor device

A semiconductor device includes a substrate having an upper surface on which are arranged first transistors each including a mesa structure formed of a semiconductor. A first bump having a shape elongated in one direction in plan view and connected to the first transistors is arranged at a position overlapping the first transistors in plan view. A second bump has a space with respect to the first bump in a direction orthogonal to a longitudinal direction of the first bump. A first metal pattern is arranged between the first and second bumps in plan view. When the upper surface of the substrate is taken as a height reference, a center of the first metal pattern in a thickness direction has a height higher than an upper surface of the mesa structure included in each of the first transistors and lower than a lower surface of the first bump.

A first layer conductor film is connected to an operation electrode through an opening in a first layer interlayer insulating film. An opening in a second layer interlayer insulating film is encompassed by the first layer conductor film in plan view. A second layer conductor film is connected to the first layer conductor film through the opening in a second layer interlayer insulating film. The average, along a first direction, of distances in a second direction, which is perpendicular to the first direction, from the opening in the first layer interlayer insulating film to the side surface of the opening in the second layer interlayer insulating film is greater than or equal to a distance in a height direction from an upper opening plane of the opening in the first layer interlayer insulating film to a lower opening plane of the opening in the second layer interlayer insulating film.

In an elastic wave device, an IDT electrode is provided on a piezoelectric substrate and a first silicon oxide film covers the IDT electrode. A high-acoustic-velocity dielectric film covers the first silicon oxide film. A second silicon oxide film is provided on the high-acoustic-velocity dielectric film. The piezoelectric substrate is made of lithium niobate. The high-acoustic-velocity dielectric film propagates longitudinal waves at an acoustic velocity higher than an acoustic velocity of longitudinal waves propagating through the first silicon oxide film. The high-acoustic-velocity dielectric film is provided at a distance of about (t+t)&#xd7;0.42 or less from a first main surface of the piezoelectric substrate in a thickness direction of the piezoelectric substrate.

An elastic wave device includes a high-acoustic-velocity member, a low-acoustic-velocity film, a piezoelectric film, and am interdigital transducer electrode stacked in this order. The interdigital transducer electrode includes an intersecting region and outer edge regions. The intersecting region includes a central region located in the middle of the intersecting region in the direction in which electrode fingers extend and the inner edge regions located at the respective outer side portions of the central region. The electrode fingers in the inner edge regions have a larger thickness than in the central region. Each electrode finger has an incrased thickness portion. The increased thickness portion is made of a metal having a density d of about 5.5 g/cmor more and has a film thickenss equal to or smaller than a wavelength-normalized film thickness represented by T (%)=&#x2212;0.1458d+4.8654.

Elastic wave device, high-frequency front-end circuit, and communication apparatus

An elastic wave device includes a piezoelectric substrate, an IDT electrode including a first electrode layer located on the piezoelectric substrate and including one of Mo and W as a main component and a second electrode layer laminated on the first electrode layer and including Cu as a main component, and a dielectric film located on the piezoelectric substrate and covering the IDT electrode. The piezoelectric substrate is made of lithium niobate. The dielectric film is made of silicon oxide. The elastic wave device utilizes Rayleigh waves propagating along the piezoelectric substrate.

Elastic wave device, high-frequency front end circuit, and communication apparatus

An elastic wave device includes a piezoelectric layer, an IDT electrode on the piezoelectric layer, a high-acoustic-velocity member, a low-acoustic-velocity film between the high-acoustic-velocity member and the piezoelectric layer. The piezoelectric layer is made of lithium tantalate, the IDT electrode includes metal layers including an Al metal layer and a metal layer having a higher density than Al. Expression 1 is satisfied: 301.74667&#x2212;10.83029&#xd7;T&#x2212;3.52155&#xd7;T+0.10788&#xd7;T+0.01003&#xd7;T+0.03989&#xd7;T&#xd7;T&#x2265;0 expression 1, where &#x3bb; represents a wavelength defined by an electrode finger pitch of the IDT electrode, T(%) represents a normalized film thickness of the piezoelectric layer to the wavelength &#x3bb;, and T(%) represents a normalized film thickness of the IDT electrode in terms of Al to the wavelength &#x3bb;.

A composite filter device includes an antenna common terminal, a first band pass filter having a first pass band, and a second band pass filter having a second pass band located at higher frequencies than the first pass band. The first band pass filter includes an elastic wave resonator. The elastic wave resonator includes a LiNbOsubstrate, an IDT electrode on the LiNbOsubstrate, and a dielectric film that covers the IDT electrode and includes a silicon oxide as a main component. When f' is the frequency of a Sezawa wave of the first band pass filter and fis the center frequency of the second pass band, f&#x2032; is located at a different position from f

Composite filter device, high-frequency front end circuit, and communication device

An elastic wave device includes a piezoelectric substrate and an interdigital transducer electrode on the piezoelectric substrate, the piezoelectric substrate including a piezoelectric layer and a high-acoustic-velocity member layer, the piezoelectric layer being stacked on the high-acoustic-velocity member layer. The piezoelectric layer is made of lithium tantalate. Denoting an elastic wave propagation direction as a first direction, and a direction perpendicular or substantially perpendicular to the first direction as a second direction, a central region, low-acoustic-velocity regions, and high-acoustic-velocity regions are provided in the interdigital transducer electrode in the second direction. The low-acoustic-velocity regions include mass-adding films on electrode fingers. Denoting a film thickness normalized to a wavelength determined by the electrode finger pitch of the interdigital transducer electrode as a wavelength-normalized film thickness (%), a product of the wavelength-normalized film thickness of the mass-adding films and the density (g/cm) of the mass-adding films is about 13.4631 or less.

An elastic wave device includes a piezoelectric substrate made of lithium niobate, an interdigital transducer electrode on the piezoelectric substrate, and a silicon oxide layer that covers the interdigital transducer electrode. The interdigital transducer electrode includes an AlCu layer and a metal layer disposed closer to the piezoelectric substrate than the AlCu layer, the metal layer having a higher density than the silicon oxide layer. The AlCu layer has a Cu concentration of about 13% or more by weight.

An elastic wave device includes a piezoelectric substrate and an interdigital transducer (IDT) electrode. The IDT electrode is disposed on the piezoelectric substrate and includes an electrode layer including molybdenum as a main component. The duty ratio of the IDT electrode is about 0.3 to about 0.48.

Elastic wave device, filter, multiplexer, radio-frequency front-end circuit, and communication device

An elastic wave device includes a first filter including an elastic wave resonator and a second filter connected to an antenna common terminal via a common node. When a first pass band of the first filter and second pass bands of the second filters are Fand Frespectively, F&#x3c;FThe first filter includes at least one elastic wave resonator, and the elastic wave resonator uses Rayleigh waves propagating on a piezoelectric substrate made of LiNbO, IDT electrodes including a Pt film on a piezoelectric layer made of LiNbO, and a silicon oxide film covering the IDT electrodes. The thickness of the silicon oxide layer is about 33% or less of the wavelength of the IDT electrodes.

Elastic wave device, radio-frequency front-end circuit, and communication device

A composite filter device for use in carrier aggregation includes a first bandpass filter connected to an antenna common terminal and including a first pass band, and a second bandpass filter including a second pass band of a higher frequency than the first pass band. The first bandpass filter includes an LiNbOsubstrate, an IDT electrode which is provided on the LiNbOsubstrate and defines the first bandpass filter, and a dielectric film which covers the IDT electrode and includes silicon oxide as a main component. The first bandpass filter is defined by at least one elastic wave resonator, and a Rayleigh wave propagating in the LiNbOsubstrate is used and an acoustic velocity of a Sezawa wave in the elastic wave resonator is equal to or higher than about 4643.2 m/sec.

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Nagaokakyo, Japan

Mari Saji