Panasonic Intellectual Property Management Co., Ltd.

Nuvoton Technology Corporation Japan

Panasonic Corporation

Panasonic Semiconductor Solutions Co., Ltd.

Shinichi Yoneda

Takumi Mikawa

Satoru Ito

Satoru Fujii

Yukio Hayakawa

Koji Katayama

Zhiqiang Wei

Ken Kawai

Kazunari Homma

Shunsaku Muraoka

Yoshio Kawashima

Takeki Ninomiya

Kiyotaka Tsuji

Atsushi Himeno

Akifumi Kawahara

Koichi Kawashima

Ryoichi Suzuki

Hiroyuki Akinaga

Hisashi Shima

Yasuhisa Naito

A gas sensor includes a gas detecting element that includes a first electrode, a metal oxide layer, and a second electrode; and a first insulating film that has an opening allowing the second electrode to be partially exposed therethrough and covers the first electrode, the metal oxide layer, and another part of the second electrode. The metal oxide layer has a characteristic where its resistance value changes as the second electrode makes contact with gas molecules including hydrogen atoms. A first step is provided at a portion lying on an interface between the metal oxide layer and the second electrode and located within the opening as viewed in plan view. A local region is provided in the metal oxide layer and near the first step. A degree of oxygen deficiency of the local region is greater than a degree of oxygen deficiency of other regions in the metal oxide layer.

Gas sensor, method of manufacturing gas sensor, and fuel cell vehicle

A gas sensor includes: a gas-sensitive body layer disposed above a substrate and including a metal oxide layer; a first electrode on the gas-sensitive body layer; and a second electrode on the gas-sensitive body layer, being apart from the first electrode by a gap. The gas-sensitive body layer has a resistance change characteristic that reversibly transitions to a high-resistance state and a low-resistance state on basis of a voltage applied across the first electrode and the second electrode. At least a part of the gas-sensitive body layer is exposed to the gap. The gas-sensitive body layer has a resistance that decreases when gas containing a hydrogen atom is in contact with the second electrode.

Gas sensor and fuel cell vehicle

A gas monitoring system includes at least one sensor device that detects gas and outputs a detection result; and a gateway that receives the detection result. The at least one sensor device includes a sensor module having a gas sensor that detects gas; an analog-to-digital (A/D) converter that processes the detection result outputted from the gas sensor; a communication module that communicates with the sensor module and transmits information processed by the A/D converter exteriorly of the at least one sensor device; a power source that is an electric power source of the sensor module; and a power source that is an electric power source of the communication module.

Sensor device and gas monitoring system

A gas detection device includes a gas sensor and a drive circuit. The drive circuit includes a measurement circuit, a power supply circuit, and a control circuit. The gas sensor includes a first electrode, a second electrode, a metal-oxide layer disposed between the first electrode and the second electrode, and an insulating film that covers the first electrode, the second electrode, and the metal-oxide layer, and has an opening that exposes part of a main surface of the second electrode. A resistance value of the metal-oxide layer decreases when gas containing hydrogen atoms contact the second electrode. When the resistance value of the metal-oxide layer falls outside a predetermined range, the drive circuit applies a predetermined voltage between the first electrode and the second electrode to restore the resistance value of the metal-oxide layer back into the predetermined range.

Gas detection device, gas sensor system, fuel cell vehicle, and hydrogen detection method

A hydrogen detection apparatus includes a hydrogen sensor, a sensor control circuit configured to sense a resistance value of the hydrogen sensor, and a microcomputer configured to set an off time that differs depending on an operating environment and intermittently drive the sensor control circuit. The hydrogen sensor includes a first electrode; a metal-oxide layer on the first electrode, and in which a resistance value is configured to change in response to contacting hydrogen atoms; a second electrode on the metal-oxide layer; and an insulating film that covers at least a portion of lateral surfaces of the first electrode, the metal-oxide layer, and the second electrode. A portion of at least one of: (i) a first interface between the first electrode and the metal-oxide layer; and (ii) a second interface between the second electrode and the metal-oxide layer is uncovered by the insulating film and exposed to a detection space.

Hydrogen detection apparatus, fuel cell vehicle, hydrogen leak monitoring system, compound sensor module, hydrogen detection method, and recording medium

A nonvolatile memory element including: a first electrode; a second electrode; a variable resistance layer that is between the first electrode and the second electrode and includes, as stacked layers, a first variable resistance layer connected to the first electrode and a second variable resistance layer connected to the second electrode; and a side wall protecting layer that has oxygen barrier properties and covers a side surface of the variable resistance layer. The first variable resistance layer includes a first metal oxide and a third metal oxide formed around the first metal oxide and having an oxygen deficiency lower than that of the first metal oxide, and the second variable resistance layer includes a second metal oxide having an oxygen deficiency lower than that of the first metal oxide.

Nonvolatile memory element, nonvolatile memory device, nonvolatile memory element manufacturing method, and nonvolatile memory device manufacturing method

A variable resistance nonvolatile storage element includes: a first electrode; a second electrode; and a variable resistance layer having a resistance value that reversibly changes based on an electrical signal applied between the electrodes, wherein the variable resistance layer has a structure formed by stacking a first transition metal oxide layer, a second transition metal oxide layer, and a third transition metal oxide layer in this order, the first transition metal oxide layer having a composition expressed as MO(where M is a transition metal and O is oxygen), the second transition metal oxide layer having a composition expressed as MO(where x&#x3e;y), and the third transition metal oxide layer having a composition expressed as MO(where y&#x3e;z).

Nonvolatile storage element and method for manufacturing same

A nonvolatile memory element includes: a first electrode; a second electrode; and a variable resistance layer between the first and second electrodes. The variable resistance layer having a resistance value that reversibly changes according to an electrical signal provided between the electrodes. The variable resistance layer includes a first variable resistance layer and a second variable resistance layer. The first variable resistance layer comprises a first metal oxide. The second variable resistance layer is planar and includes a first part and a second part. The first part comprises a second metal oxide and is planar. The second part comprises an insulator and is planar. The second metal oxide has a lower oxygen deficient degree than that of the first metal oxide. The first and second parts are in contact with different parts of a main surface of the first variable resistance layer which faces the second variable resistance layer.

Nonvolatile memory element and method of manufacturing nonvolatile memory element

A method of manufacturing a non-volatile memory element includes forming a first electrode; forming a variable resistance layer; and forming a second electrode. Forming the variable resistance layer includes forming a third metal oxide layer having a third metal oxide, forming a second metal oxide layer having a second metal oxide, and forming a first metal oxide layer e having a first metal oxide; wherein the variable resistance layer reversibly changes its resistance value in response to an electric signal applied between the first electrode and the second electrode; the first metal oxide is lower in degree of oxygen deficiency than the third metal oxide; the second metal oxide is lower in degree of oxygen deficiency than the third metal oxide; the third metal oxide is an oxygen-deficient metal oxide; and the first metal oxide layer is different in density from the second metal oxide layer.

Manufacturing method of non-volatile memory element, non-volatile memory element, and non-volatile memory device

In a method of manufacturing a variable resistance non-volatile memory device including non-volatile memory element layers stacked together by repeating the step (S, S. . . ) of forming a non-volatile memory element layer plural times, when a thickness of the second metal oxide layer included in each of the non-volatile memory element layers just after the step of forming the corresponding non-volatile memory element layer is completed is a thickness in formation, and when an area of a portion of the second metal oxide layer included in each of the non-volatile memory element layers and a portion of the first metal oxide layer included in the corresponding non-volatile memory element layer, which portions are in contact with each other, just after the step of forming the corresponding non-volatile memory element layer is completed is an area in formation, at least one of the thickness in formation and the area in formation is made different among the steps of forming the non-volatile memory element layers, to cause all of the non-volatile memory elements in a state in which formation of an uppermost non-volatile memory element layer is completed, to have an equal initial resistance.

Variable resistance non-volatile memory device and manufacturing method thereof

A method of designing a cross-point non-volatile memory device including memory elements arranged in (N&#xd7;M) matrix, each of the memory elements including a variable resistance element and a bidirectional current steering element connected in series with the variable resistance element, the method comprises the step of: when an absolute value of a low-resistance state writing voltage is VR and an absolute value of a current flowing through the variable resistance element having changed to a low-resistance state by application of the low-resistance state writing voltage to both ends of the variable resistance element in a high-resistance state is I, and a relationship between a voltage Vapplied to both ends of the bidirectional current steering element and a current I flowing through the bidirectional current steering element is approximated as |V|=a&#xd7;Log(I)+b, deciding N, M, VR, I, a, and b such that b&#x2212;VR/2&#x3e;a&#xd7;[Log {(N&#x2212;1)&#xd7;(M&#x2212;1)}&#x2212;Log(I)] is satisfied (S).

Designing method of non-volatile memory device, manufacturing method of non-volatile memory device, and non-volatile memory device

A nonvolatile memory element includes a first electrode, a second electrode, and a variable resistance layer positioned between the first electrode and the second electrode. The variable resistance layer has a resistance state which reversibly changes based on an electrical signal applied between the first electrode and the second electrode. The variable resistance layer includes a first variable resistance layer having a first metal oxide and a second variable resistance layer having a second metal oxide. The second variable resistance layer includes a metal-metal bonding region including a metal bond of metal atoms included in the second metal oxide, and the second metal oxide has a low degree of oxygen deficiency and a high resistance value compared to the first metal oxide.

Nonvolatile memory element and method for manufacturing the same

A nonvolatile memory element according to the present disclosure includes: a variable resistance element including a first electrode layer, a second electrode layer, and a variable resistance layer which is located between the first electrode layer and the second electrode layer and has a resistance value that reversibly changes based on an electrical signal applied between the first electrode layer and the second electrode layer; and a fixed resistance layer having a predetermined resistance value and stacked together with the variable resistance element. The variable resistance layer includes (i) a first transition metal oxide layer which is oxygen deficient and (ii) a second transition metal oxide layer which has a higher oxygen content atomic percentage than the first transition metal oxide layer. The predetermined resistance value ranges from 70&#x3a9; to 1000&#x3a9; inclusive.

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Kyoto, Japan

Shinichi Yoneda