Abstract: In a semiconductor device using a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The semiconductor device includes a gate electrode over an insulating surface; an oxide semiconductor film overlapping with the gate electrode; a gate insulating film that is between the gate electrode and the oxide semiconductor film and in contact with the oxide semiconductor film; a protective film in contact with a surface of the oxide semiconductor film that is an opposite side of a surface in contact with the gate insulating film; and a pair of electrodes in contact with the oxide semiconductor film. The spin density of the gate insulating film or the protective film measured by electron spin resonance spectroscopy is lower than 1×1018 spins/cm3, preferably higher than or equal to 1×1017 spins/cm3 and lower than 1×1018 spins/cm3.

Abstract: A Compton camera includes a scattering detection unit, an absorption detection unit, a signal processing unit, a first shield unit, and a second shield unit. The scattering detection unit detects Compton scattering of incident radiation emitted from a radiation source. The absorption detection unit detects absorption of incident radiation that has undergone Compton scattering at the scattering detection unit. The signal processing unit obtains an image of the radiation source based on coincident detection events of Compton scattering of radiation at the scattering detection unit and absorption of radiation at the absorption detection unit. The first and second shield units are provided between the scattering detection unit and the absorption detection unit. The first shield unit selectively allows forward-scattered radiation to pass and selectively blocks back-scattered radiation.

Abstract: The amount of lithium ions that can be received and released in and from a positive electrode active material is increased, and high capacity and high energy density of a secondary battery are achieved. Provided is a lithium-manganese composite oxide represented by LixMnyMzOw, where M is a metal element other than Li and Mn, or Si or P, and y, z, and w satisfy 0?x/(y+z)<2, y>0, z>0, 0.26?(y+z)/w<0.5, and 0.2<z/y<1.2. The lithium manganese composite oxide has high structural stability and high capacity.

Abstract: A semiconductor device including a transistor having a reduced number of oxygen vacancies in a channel formation region of an oxide semiconductor with stable electrical characteristics or high reliability is provided. A gate insulating film is formed over a gate electrode; an oxide semiconductor layer is formed over the gate insulating film; an oxide layer is formed over the oxide semiconductor layer by a sputtering method to form an stacked-layer oxide film including the oxide semiconductor layer and the oxide layer; the stacked-layer oxide film is processed into a predetermined shape; a conductive film containing Ti as a main component is formed over the stacked-layer oxide film; the conductive film is etched to form source and drain electrodes and a depression portion on a back channel side; and portions of the stacked-layer oxide film in contact with the source and drain electrodes are changed to an n-type by heat treatment.

Abstract: The amount of lithium ions that can be received and released in and from a positive electrode active material is increased, and high capacity and high energy density of a secondary battery are achieved. Provided is a lithium-manganese composite oxide represented by LixMnyMzOw, where M is a metal element other than Li and Mn, or Si or P, and y, z, and w satisfy 0?x/(y+z)<2, y>0, z>0, 0.26?(y+z)/w<0.5, and 0.2<z/y<1.2. The lithium manganese composite oxide has high structural stability and high capacity.

Abstract: A semiconductor device including a transistor having a reduced number of oxygen vacancies in a channel formation region of an oxide semiconductor with stable electrical characteristics or high reliability is provided. A gate insulating film is formed over a gate electrode; an oxide semiconductor layer is formed over the gate insulating film; an oxide layer is formed over the oxide semiconductor layer by a sputtering method to form an stacked-layer oxide film including the oxide semiconductor layer and the oxide layer; the stacked-layer oxide film is processed into a predetermined shape; a conductive film containing Ti as a main component is formed over the stacked-layer oxide film; the conductive film is etched to form source and drain electrodes and a depression portion on a back channel side; and portions of the stacked-layer oxide film in contact with the source and drain electrodes are changed to an n-type by heat treatment.

Abstract: A reverse bias voltage is applied to a photodiode array provided with a plurality of avalanche photodiodes operated in Geiger mode and with quenching resistors connected in series to the respective avalanche photodiodes. Electric current is measured with change of the reverse bias voltage applied, and the reverse bias voltage at an inflection point in change of electric current measured is determined as a reference voltage. A voltage obtained by adding a predetermined value to the determined reference voltage is determined as a recommended operating voltage.

Abstract: To increase the amount of lithium ions that can be received in and released from a positive electrode active material to achieve high capacity and high energy density of a secondary battery. A lithium manganese oxide particle includes a first region and a second region. The valence number of manganese in the first region is lower than the valence number of manganese in the second region. The lithium manganese oxide has high structural stability and high capacity characteristics.

Abstract: In a semiconductor device using a transistor including an oxide semiconductor, a change in electrical characteristics is suppressed and reliability is improved. The semiconductor device includes a gate electrode over an insulating surface; an oxide semiconductor film overlapping with the gate electrode; a gate insulating film that is between the gate electrode and the oxide semiconductor film and in contact with the oxide semiconductor film; a protective film in contact with a surface of the oxide semiconductor film that is an opposite side of a surface in contact with the gate insulating film; and a pair of electrodes in contact with the oxide semiconductor film. The spin density of the gate insulating film or the protective film measured by electron spin resonance spectroscopy is lower than 1×1018 spins/cm3, preferably higher than or equal to 1×1017 spins/cm3 and lower than 1×1018 spins/cm3.

Abstract: The amount of lithium ions that can be received and released in and from a positive electrode active material is increased, and high capacity and high energy density of a secondary battery are achieved. Provided is a lithium-manganese composite oxide represented by LixMnyMzOw, where M is a metal element other than Li and Mn, or Si or P, and y, z, and w satisfy 0?x/(y+z)<2, y>0, z>0, 0.26?(y+z)/w<0.5, and 0.2<z/y<1.2. The lithium manganese composite oxide has high structural stability and high capacity.

Abstract: With a small amount of a conductive additive, an electrode for a storage battery including an active material layer which is highly filled with an active material is provided. The use of the electrode enables fabrication of a storage battery having high capacity per unit volume of the electrode. By using graphene as a conductive additive in an electrode for a storage battery including a positive electrode active material, a network for electron conduction through graphene is formed. Consequently, the electrode can include an active material layer in which particles of an active material are electrically connected to each other by graphene. Therefore, graphene is used as a conductive additive in an electrode for a sodium-ion secondary battery including an active material with low electric conductivity, for example, an active material with a band gap of 3.0 eV or more.

Abstract: A semiconductor device including a transistor having a reduced number of oxygen vacancies in a channel formation region of an oxide semiconductor with stable electrical characteristics or high reliability is provided. A gate insulating film is formed over a gate electrode; an oxide semiconductor layer is formed over the gate insulating film; an oxide layer is formed over the oxide semiconductor layer by a sputtering method to form an stacked-layer oxide film including the oxide semiconductor layer and the oxide layer; the stacked-layer oxide film is processed into a predetermined shape; a conductive film containing Ti as a main component is formed over the stacked-layer oxide film; the conductive film is etched to form source and drain electrodes and a depression portion on a back channel side; and portions of the stacked-layer oxide film in contact with the source and drain electrodes are changed to an n-type by heat treatment.

Abstract: A reverse bias voltage is applied to a photodiode array provided with a plurality of avalanche photodiodes operated in Geiger mode and with quenching resistors connected in series to the respective avalanche photodiodes. Electric current is measured with change of the reverse bias voltage applied, and the reverse bias voltage at an inflection point in change of electric current measured is determined as a reference voltage. A voltage obtained by adding a predetermined value to the determined reference voltage is determined as a recommended operating voltage.

Abstract: Graphene which is permeable to lithium ions and can be used for electric appliances is provided. A carbocyclic ring including nine or more ring members is provided in graphene. The maximum potential energy of the carbocyclic ring including nine or more ring members to a lithium ion is substantially 0 eV. Therefore, the carbocyclic ring including nine or more ring members can function as a hole through which lithium ions pass. When a surface of an electrode or an active material is coated with such graphene, reaction of the electrode or the active material with an electrolyte can be suppressed without interference with the movement of lithium ions.