Abstract: Provided are a semiconductor film including silicon microstructures formed at high density, and a manufacturing method thereof. Further, provided are a semiconductor film including silicon microstructures whose density is controlled, and a manufacturing method thereof. Furthermore, a power storage device with improved charge-discharge capacity is provided. A manufacturing method in which a semiconductor film with a silicon layer including silicon structures is formed over a substrate with a metal surface is used. The thickness of a silicide layer formed by reaction between the metal and the silicon is controlled, so that the grain sizes of silicide grains formed at an interface between the silicide layer and the silicon layer are controlled and the shapes of the silicon structures are controlled. Such a semiconductor film can be applied to an electrode of a power storage device.

Abstract: A technique for manufacturing a microcrystalline semiconductor layer with high mass productivity is provided. In a reaction chamber of a plasma CVD apparatus, an upper electrode and a lower electrode are provided in almost parallel to each other. A hollow portion is formed in the upper electrode, and the upper electrode includes a shower plate having a plurality of holes formed on a surface of the upper electrode which faces the lower electrode. A substrate is provided over the lower electrode. A gas containing a deposition gas and hydrogen is supplied to the reaction chamber from the shower plate through the hollow portion of the upper electrode, and a rare gas is supplied to the reaction chamber from a portion different from the upper electrode. Accordingly, high-frequency power is supplied to the upper electrode to generate plasma, so that a microcrystalline semiconductor layer is formed over the substrate.

Abstract: An object of the present invention is to provide a technique for manufacturing a dense crystalline semiconductor film without a cavity between crystal grains. A plasma region is formed between a first electrode and a second electrode by supplying high-frequency power of 60 MHz or less to the first electrode under a condition where a pressure of a reactive gas in a reaction chamber of a plasma CVD apparatus is set to 450 Pa to 13332 Pa, and a distance between the first electrode and the second electrode of the plasma CVD apparatus is set to 1 mm to 20 mm; crystalline deposition precursors are formed in a gas phase including the plasma region; a crystal nucleus of 5 nm to 15 nm is formed by depositing the deposition precursors; and a microcrystalline semiconductor film is formed by growing a crystal from the crystal nucleus.

Abstract: Provided are a semiconductor film including silicon microstructures formed at high density, and a manufacturing method thereof. Further, provided are a semiconductor film including silicon microstructures whose density is controlled, and a manufacturing method thereof. Furthermore, a power storage device with improved charge-discharge capacity is provided. A manufacturing method in which a semiconductor film with a silicon layer including silicon structures is formed over a substrate with a metal surface is used. The thickness of a silicide layer formed by reaction between the metal and the silicon is controlled, so that the grain sizes of silicide grains formed at an interface between the silicide layer and the silicon layer are controlled and the shapes of the silicon structures are controlled. Such a semiconductor film can be applied to an electrode of a power storage device.

Abstract: The contact resistance between an oxide semiconductor film and a metal film is reduced. A transistor that uses an oxide semiconductor film and has excellent on-state characteristics is provided. A semiconductor device capable of high-speed operation is provided. In a transistor that uses an oxide semiconductor film, the oxide semiconductor film is subjected to nitrogen plasma treatment. Thus, part of oxygen included in the oxide semiconductor film is replaced with nitrogen, so that an oxynitride region is formed. A metal film is formed in contact with the oxynitride region. The oxynitride region has lower resistance than the other region of the oxide semiconductor film. In addition, the oxynitride region is unlikely to form high-resistance metal oxide at the interface with the contacting metal film.

Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.

Abstract: An object is to provide a thin film transistor with small off current, large on current, and high field-effect mobility. A silicon nitride layer and a silicon oxide layer which is formed by oxidizing the silicon nitride layer are stacked as a gate insulating layer, and crystals grow from an interface of the silicon oxide layer of the gate insulating layer to form a microcrystalline semiconductor layer; thus, an inverted staggered thin film transistor is manufactured. Since crystals grow from the gate insulating layer, the thin film transistor can have a high crystallinity, large on current, and high field-effect mobility. In addition, a buffer layer is provided to reduce off current.

Abstract: A method for manufacturing a microcrystalline semiconductor film having high crystallinity is provided. A method for manufacturing a semiconductor device which has favorable electric characteristics with high productivity is provided. After a first microcrystalline semiconductor film is formed over a substrate, treatment for flattening a surface of the first microcrystalline semiconductor film is performed. Then, treatment for removing an amorphous semiconductor region on a surface side of the flattened first microcrystalline semiconductor film is performed so that a second microcrystalline semiconductor film having high crystallinity and flatness is formed. After that, a third microcrystalline semiconductor film is formed over the second microcrystalline semiconductor film.

Abstract: A transistor which includes an oxide semiconductor and is capable of high-speed operation and a method of manufacturing the transistor. In addition, a highly reliable semiconductor device including the transistor and a method of manufacturing the semiconductor device. The semiconductor device includes an oxide semiconductor layer including a channel formation region, and a source and drain regions which are provided so that the channel formation region is interposed therebetween and have lower resistance than the channel formation region. The channel formation region and the source and drain regions each include a crystalline region.

Abstract: An object of the present invention is to provide a technique for manufacturing a dense crystalline semiconductor film without a cavity between crystal grains. A plasma region is formed between a first electrode and a second electrode by supplying high-frequency power of 60 MHz or less to the first electrode under a condition where a pressure of a reactive gas in a reaction chamber of a plasma CVD apparatus is set to 450 Pa to 13332 Pa, and a distance between the first electrode and the second electrode of the plasma CVD apparatus is set to 1 mm to 20 mm; crystalline deposition precursors are formed in a gas phase including the plasma region; a crystal nucleus of 5 nm to 15 nm is formed by depositing the deposition precursors; and a microcrystalline semiconductor film is formed by growing a crystal from the crystal nucleus.

Abstract: An object of one embodiment of the present invention is to provide a technique for manufacturing a dense crystalline semiconductor film (e.g., a microcrystalline semiconductor film) without a cavity between crystal grains. A plasma region is formed between a first electrode and a second electrode by supplying high-frequency power of 60 MHz or less to the first electrode under a condition where a pressure of a reactive gas in a reaction chamber of a plasma CVD apparatus is set to 450 Pa to 13332 Pa, and a distance between the first electrode and the second electrode of the plasma CVD apparatus is set to 1 mm to 20 mm; crystalline deposition precursors are formed in a gas phase including the plasma region; a crystal nucleus of 5 nm to 15 nm is formed by depositing the deposition precursors; and a microcrystalline semiconductor film is formed by growing a crystal from the crystal nucleus.

Abstract: A hydrogen generating element which can supply hydrogen efficiently and stably, is safe, and has low environmental load is provided. Further, a hydrogen generation device to which the hydrogen generating element is applied is provided. Furthermore, a power generation device and a driving device to each of which the hydrogen generation device is applied are provided. A hydrogen generating element in which a needle-like or dome-like silicon microstructure is formed over a base may be used and reacted with water, whereby hydrogen is efficiently generated. The hydrogen generating element may be applied to a hydrogen generation device. The hydrogen generation device may be applied to a power generation device and a driving device.

Abstract: To provide a photoelectric conversion device with improved photoelectric conversion characteristics and cost competitiveness. A photoelectric conversion device including a semiconductor junction has a semiconductor layer in which a needle-like crystal is made to grow over an impurity semiconductor layer. The impurity semiconductor layer is formed of a microcrystalline semiconductor and includes an impurity imparting one conductivity type. An amorphous semiconductor layer is deposited on a microcrystalline semiconductor layer by setting the flow rate of a dilution gas (typically silane) to 1 time to 6 times the flow rate of a semiconductor source gas (typically hydrogen) at the time of deposition. Thus, a crystal with a three-dimensional shape tapered in a direction of the deposition of a film, i.e., in a direction from the microcrystalline semiconductor layer to the amorphous semiconductor layer is made to grow.

Abstract: Provided are a semiconductor film including silicon microstructures formed at high density, and a manufacturing method thereof. Further, provided are a semiconductor film including silicon microstructures whose density is controlled, and a manufacturing method thereof Furthermore, a power storage device with improved charge-discharge capacity is provided. A manufacturing method in which a semiconductor film with a silicon layer including silicon structures is formed over a substrate with a metal surface is used. The thickness of a silicide layer formed by reaction between the metal and the silicon is controlled, so that the grain sizes of silicide grains formed at an interface between the silicide layer and the silicon layer are controlled and the shapes of the silicon structures are controlled. Such a semiconductor film can be applied to an electrode of a power storage device.

Abstract: A technique for manufacturing a microcrystalline semiconductor layer with high mass productivity is provided. In a reaction chamber of a plasma CVD apparatus, an upper electrode and a lower electrode are provided in almost parallel to each other. A hollow portion is formed in the upper electrode, and the upper electrode includes a shower plate having a plurality of holes formed on a surface of the upper electrode which faces the lower electrode. A substrate is provided over the lower electrode. A gas containing a deposition gas and hydrogen is supplied to the reaction chamber from the shower plate through the hollow portion of the upper electrode, and a rare gas is supplied to the reaction chamber from a portion different from the upper electrode. Accordingly, high-frequency power is supplied to the upper electrode to generate plasma, so that a microcrystalline semiconductor layer is formed over the substrate.

Abstract: A non-single-crystal semiconductor layer is formed over a substrate, and then a single crystal semiconductor layer is formed over part of the non-single-crystal semiconductor layer. Thus, a semiconductor element of a region which requires a large area (e.g. a pixel region in a display device) can be formed using the non-single-crystal semiconductor layer, and a semiconductor element of a region which requires high speed operation (e.g. a driver circuit region in a display device) can be formed using the single crystal semiconductor layer.

Abstract: A technique for manufacturing a microcrystalline semiconductor layer with high mass productivity is provided. In a reaction chamber of a plasma CVD apparatus, an upper electrode and a lower electrode are provided in almost parallel to each other. A hollow portion is formed in the upper electrode, and the upper electrode includes a shower plate having a plurality of holes formed on a surface of the upper electrode which faces the lower electrode. A substrate is provided over the lower electrode. A gas containing a deposition gas and hydrogen is supplied to the reaction chamber from the shower plate through the hollow portion of the upper electrode, and a rare gas is supplied to the reaction chamber from a portion different from the upper electrode. Accordingly, high-frequency power is supplied to the upper electrode to generate plasma, so that a microcrystalline semiconductor layer is formed over the substrate.

Abstract: Provided is a structure to obtain a reliable electrical contact through a narrow contact hole formed in an insulating layer, which is required in the miniaturization of a semiconductor device. An exemplified structure includes a thin film transistor comprising: a lower electrode over and in contact with a semiconductor layer, the lower electrode comprising a metal or a metal compound; an insulating layer over the lower electrode, the insulating layer having a contact hole reaching the lower electrode; a conductive silicon whisker grown from a surface of the lower electrode; and an upper electrode over the insulating layer and in contact with the conductive silicon whisker. The ability of the conductive silicon whisker grown from the lower electrode to ohmically contact with the lower and upper electrodes leads to a reliable electrical contact between the thin film transistor and a wiring.

Abstract: A novel photoelectric conversion device in which energy of light can be effectively utilized and performance can be improved is provided. A photoelectric conversion device includes a photoelectric conversion element and an energy conversion layer provided on a light-receiving side of a photoelectric conversion layer included in the photoelectric conversion element. The energy conversion layer includes a plurality of first layers and a plurality of second layers. The first layer and the second layer are alternately stacked. The thickness of the first layer is greater than or equal to 0.5 nm and less than or equal to 10 nm, and the thickness of the second layer is greater than or equal to 0.5 nm and less than or equal to 10 nm. The second layer can be formed using a material having a larger energy band gap than that of a material used for the first layer.

Abstract: An electrode for a power storage device with less deterioration due to charge and discharge and a power storage device using the electrode are provided. In the electrode for a power storage device and the power storage device, a region including a metal element which functions as a catalyst is selectively provided over a current collector, and then, an active material layer is formed. By selectively providing the region including the metal element, a whisker can be effectively generated in the active material layer over the current collector, and the whisker generation region can be controlled. Accordingly, the discharge capacity can be increased and the cycle characteristics can be improved.