A semiconductor device in which variation of characteristics is small is provided. A second insulator, an oxide, a conductive layer, and an insulating layer are formed over a first insulator; a third insulator and fourth insulator are deposited to be in contact with the first insulator; a first opening reaching the oxide is formed in the conductive layer, the insulating layer, the third insulator, and the fourth insulator; a fifth insulator, a sixth insulator, and a conductor are formed in the first opening; a seventh insulator is deposited over the fourth insulator, the fifth insulator, and the sixth insulator; a mask is formed in a first region over the seventh insulator in a top view; oxygen is implanted into a second region not overlapping the first region in the top view; heat treatment is performed; a second opening reaching the fourth insulator is formed in the seventh insulator; and heat treatment is performed.

A semiconductor device with a small variation in transistor characteristics is provided. An oxide semiconductor film, a source electrode and a drain electrode over the oxide semiconductor film, an interlayer insulating film placed to cover the oxide semiconductor film, the source electrode, and the drain electrode, and a gate electrode over the oxide semiconductor film are included; an opening is formed overlapping with a region between the source electrode and the drain electrode in the interlayer insulating film; the gate electrode is placed in the opening in the interlayer insulating film; and the source electrode and the drain electrode include a conductive film having compressive stress.

A memory device with a small number of wirings using a NAND flash memory having a three-dimensional structure with a large number of stacked memory cell layers is provided. A decoder is formed using an OS transistor. An OS transistor can be formed by a method such as a thin film method, whereby the decoder can be provided to be stacked above the NAND flash memory having a three-dimensional structure. This can reduce the number of wirings provided substantially perpendicular to the memory cell layers.

A semiconductor device including: a first silicon layer including a first single crystal silicon and a plurality of first transistors; a first metal layer disposed over the first silicon layer; a second metal layer disposed over the first metal layer; a third metal layer disposed over the second metal layer; a second level including a plurality of second transistors, the second level disposed over the third metal layer; a fourth metal layer disposed over the second level; a fifth metal layer disposed over the fourth metal layer, a connection path from the fifth metal layer to the second metal layer, where the connection path includes a via disposed through the second level, where the via has a diameter of less than 450 nm, where the fifth metal layer includes a global power distribution grid, and where a typical thickness of the fifth metal layer is greater than a typical thickness of the second metal layer by at least 50%.

A semiconductor device with a novel structure which can identify the sound source is provided. The semiconductor device includes a microphone array, delay circuits, and a signal processing circuit. The delay circuit includes a first selection circuit, which selects a microphone, signal retention circuits, which retain voltages depending on the sound signal, and a second selection circuit, which selects a signal retention circuit. Each signal retention circuit includes a transistor which includes a semiconductor layer including an oxide semiconductor in its channel formation region. The first selection circuit writes the voltage of discreet sound signals to the signal retention circuit. The second selection circuit selects at different timings the voltages which are retained in the signal retention circuit and generates the output signal corresponding to the delayed sound signal.

A semiconductor device with a high driving speed is provided. The semiconductor device includes first to fourth cells, a converter circuit, and first to fourth wirings. The first and second cells make a first current and a second current each corresponding to the product of first data and second data flow in the first wiring and the second wiring, respectively. The third and fourth cells make base currents in the same amount flow in the first and second wirings. The converter circuit outputs, from an output terminal thereof, a voltage corresponding to the differential current between the sum of the first current and the base current flowing in the first wiring and the sum of the second current and the base current flowing in the second wiring.

A semiconductor device includes: a substrate including an active region and a device isolation region; a flat plate structure formed on the substrate; an oxide semiconductor layer covering a top surface of the flat plate structure and continuously arranged on a top surface of the substrate in the active region and the device isolation region; a gate structure arranged on the oxide semiconductor layer and including a gate dielectric layer and a gate electrode; and a source/drain region arranged on both sides of the gate structure and formed in the oxide semiconductor layer, in which, when viewed from a side cross-section, an extending direction of the flat plate structure and an extending direction of the gate structure cross each other.

To provide a display device capable of displaying a plurality of images by superimposition using a plurality of memory circuits provided in a pixel. A plurality of memory circuits are provided in a pixel, and signals corresponding to images for superimposition are retained in each of the plurality of memory circuits. In the pixel, the signals corresponding to the images for superimposition are added to each of the plurality of memory circuits. The signals are added to the signals retained in the memory circuits by capacitive coupling. A display element can display an image corresponding to a signal in which a signal written to a pixel through a wiring is added to the signals retained in the plurality of memory circuits. Reduction in the amount of arithmetic processing for displaying images by superimposition can be achieved.

A semiconductor device with a novel structure is provided. A plurality of memory circuits, a switching circuit, and an arithmetic circuit are included. Each of the plurality of memory circuits has a function of retaining weight data and a function of outputting the weight data to a first wiring. The switching circuit has a function of switching a conduction state between any one of the plurality of first wirings and a second wiring. The arithmetic circuit has a function of performing arithmetic processing using input data and the weight data supplied to the second wiring. The memory circuits are provided in a first layer. The switching circuit and the arithmetic circuit are provided in a second layer. The first layer is provided in a layer different from the second layer.

Since power source voltages are different depending on circuits used for devices, a circuit for outputting at least two or more power sources is additionally prepared. An object is to unify outputs of the power source voltages. A transistor using an oxide semiconductor is provided in such a manner that electrical charge is retained in a node where the transistor and a capacitor are electrically connected to each other, a reset signal is applied to a gate of the transistor to switch the states of the transistor from off to on, and the node is reset when the transistor is on. A circuit configuration that generates and utilizes a potential higher than or equal to a potential of a single power source can be achieved.