Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Nuvoton Technology Corporation Japan

Matsushita Electric Industrial Co., Ltd.

Panasonic Holdings Corporation

Panasonic Semiconductor Solutions Co., Ltd.

Koji Katayama

Takeshi Takagi

Shunsaku Muraoka

Satoru Mitani

Yoshihiko Kanzawa

Zhiqiang Wei

Kazunari Homma

Kazuhiko Shimakawa

Ken Kawai

Satoru Fujii

Tohru Saitoh

Akira Asai

Koichiro Yuki

Katsuya Nozawa

Yoshihiro Hara

Minoru Kubo

Ryoko Miyanaga

Yo Ichikawa

Takumi Mikawa

Koichi Osano

Kiyoshi Ohnaka

Takeki Ninomiya

Shinichi Yoneda

Mitsuteru Iijima

Satoru Ito

Teruhito Oonishi

Yoshio Kawashima

Teruhito Ohnishi

Gaku Sugahara

Kiyotaka Tsuji

Yuichiro Ikeda

Ryutaro Yasuhara

Koichi Kawashima

A hydrogen sensor includes a first electrode that is a planar electrode; a second electrode that is a planar electrode facing the first electrode and includes an exposed portion to be exposed to a gas containing hydrogen; a metal oxide layer disposed between the two facing surfaces of the first electrode and the second electrode and having the resistance value that is changed by the exposed portion being exposed to the gas; a first terminal, a second terminal, and a heat dissipation portion spaced apart from each other; one or more first vias provided above the second electrode and electrically connected to the first terminal and the second electrode; one or more second vias provided above the second electrode and electrically connected to the second terminal and the second electrode; and one or more third vias above the second electrode and in contact with the heat dissipation portion.

Hydrogen sensor

A semiconductor device includes variable resistance elements on a semiconductor substrate. Each of the variable resistance elements includes a first electrode, a second electrode, and a variable resistance layer that is sandwiched between the first electrode and the second electrode and that stores a resistance value that is continuously variable. The variable resistance layer includes a filament whose shape differs according to a neural network weight, and stores, as an analog value, the resistance value that is variable.

Semiconductor device and method of driving the same

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 variable resistance nonvolatile storage device includes: a variable resistance element having a state reversibly changeable between a high resistance state and a low resistance state; and a current supply circuit that supplies the variable resistance element with a low-resistance changing current for changing the state from the high resistance state to the low resistance state. The low-resistance changing current has a waveform that includes a first period and a second period along a time axis, the second period being subsequent to the first period. The current supply circuit applies to the variable resistance element: a first current during the first period; and a second current during the second period, the second current being smaller than the first current. The first current is not zero at an end of the first period, and the second current is not zero at a start of the second period.

Variable resistance nonvolatile storage device and write method therefor

A hydrogen sensor includes: a first electrode which is planar; a second electrode which is planar, faces the first electrode, and includes an exposed portion; a metal oxide layer which is sandwiched between a surface of the first electrode and a surface of the second electrode, and has a resistance that changes due to hydrogen; and two terminals, i.e., a first terminal and a second terminal, that are connected to the second electrode.

Hydrogen sensor, hydrogen detection method, and hydrogen detection device

A gas sensor driving method for a gas sensor that (i) includes: a first electrode including a first principal surface; a second electrode including a second principal surface; a metal-oxide layer interposed between the first principal surface and the second principal surface that face each other; and an insulating film covering the first electrode, the metal-oxide layer, and the second electrode, and exposing at least a part of a third principal surface of the second electrode, the third principal surface being disposed on an opposite side of the second principal surface, and (ii) detects hydrogen in accordance with a change in a resistance value of the metal-oxide layer. The gas sensor driving method includes repeatedly applying a positive voltage and a negative voltage across the first electrode and the second electrode.

Method for driving gas sensor, and gas detection device

Provided is a gas detection device that includes a gas sensor, a power supply circuit that applies voltage to the gas sensor, and a control circuit that determines whether a leak of gas is present. The power supply circuit includes a reset power source that generates a first voltage, and a detection power source that generates a detection voltage for measuring resistance of a metal-oxide layer of the gas sensor. When a value of a current flowing through the metal-oxide layer is a predetermined value ITH or greater, the reset power source applies the first voltage to the gas sensor to perform a reset of resetting the metal-oxide layer of the gas sensor to a high-resistance state, and the control circuit determines that a leak of gas is present, depending on a state in which the reset is performed after the reset is performed for the first time.

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

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 gas sensor includes: a first electrode; a metal oxide layer that is on the first electrode and has a resistance value that changes when the metal oxide layer contacts hydrogen atoms; a second electrode on the metal oxide layer; and an insulating film that covers at least a part of side surfaces of the first electrode, the metal oxide layer, and the second electrode. In the metal oxide layer, a part of a first interface between the first electrode and the metal oxide layer is not covered by the insulating film and is exposed to a gas.

Gas sensor, gas detection apparatus, fuel cell powered vehicle, and manufacturing method of gas sensor

A gas sensor device includes gas sensors and switches. The switches are connected to the respective gas sensors in series. The gas sensors each include: a first conductive layer; a second conductive layer; a metal oxide layer disposed between the first conductive layer and the second conductive layer; and an insulation layer covering the first conductive layer, the second conductive layer, and the metal oxide layer and having an opening from which a portion of the second conductive layer is exposed. The resistance of the gas sensor is decreased when a gas containing a hydrogen atom comes into contact with the second conductive layer.

Gas sensor device including gas sensors and switches, gas sensor module, and gas detection method

A gas-detecting apparatus includes a gas sensor and a power supply 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 insulation film covering the first electrode, the second electrode, and the metal oxide layer. The insulation file having an opening from which a surface of the second electrode is exposed. The resistance value of the metal oxide layer decreases when gas containing hydrogen atoms comes into contact with the second electrode. The power supply circuit applies a predetermined voltage between the first electrode and the second electrode to increase the resistance value of the metal oxide layer before and/or after the decrease in the resistance value of the metal oxide layer.

Gas-detecting apparatus including gas sensor and method of detecting hydrogen using gas sensor

A forming method includes: applying a first pulse voltage to a second electrode to a variable-resistance nonvolatile memory element in first state; and executing at least once a sequence that includes determining whether the variable-resistance nonvolatile memory element is in a second state, and continuously applying a second pulse voltage followed by a third pulse voltage to the variable-resistance nonvolatile memory element when the variable-resistance nonvolatile memory element is determined not to be in the second state.

Forming method for variable-resistance nonvolatile memory element

A method of driving a variable resistance element comprises: before a first write step is performed, applying an initial voltage pulse of a first polarity to change a resistance value of a metal oxide layer from a resistance value corresponding to an initial state of the metal oxide layer to another resistance value; wherein when the resistance value corresponding to the initial state is R, the resistance value corresponding to a write state is RL, the resistance value corresponding to an erase state is RH, another resistance value is R, a maximum value of the current flowing when the initial voltage pulse is applied is IbRL, a maximum value of the current flowing when the write voltage pulse is applied is IRL, and a maximum value of the current flowing when the erase voltage pulse is applied is IRH, R&#x3e;RH&#x3e;R&#x2267;RL, and |IRL|&#x3e;|IbRL| are satisfied.

Driving method of variable resistance element and non-volatile memory device

A method for programming a nonvolatile memory element includes: decreasing a resistance value of a variable resistance element in an initial state, by applying an initialization voltage pulse to a series circuit in which a load resistor having a first resistance value is connected in series with the variable resistance element and a MSM diode; applying, after the decreasing, a write voltage pulse to the series circuit after the resistance value of the variable resistance element is changed to a second resistance value lower than the first resistance value; and applying, after the decreasing, an erase voltage pulse to the series circuit after the resistance value of the variable resistance element is changed to a third resistance value lower than the first resistance value.

Method for programming nonvolatile memory element, method for initializing nonvolatile memory element, and nonvolatile memory device

A driving method for driving a variable resistance element and a nonvolatile memory device, which achieves stable storage operation. In a low resistance write process, a low resistance writing voltage pulse having the negative polarity is applied once to a variable resistance layer included in a variable resistance element while in a high resistance write process, a high resistance writing voltage pulse having the positive polarity is applied more than twice to the same variable resistance layer. Here, when a voltage value of one of the high resistance writing voltage pulses is VHand a voltage value of the other high resistance writing voltage pulse applied subsequently is VH, VH&#x3e;VHis satisfied.

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Nara, Japan

Koji Katayama