摘要:
As an electrode for a power storage device, an electrode including a current collector, a first active material layer over the current collector, and a second active material layer that is over the first active material layer and includes a particle containing niobium oxide and a granular active material is used, whereby the charge-discharge cycle characteristics and rate characteristics of the power storage device can be improved. Moreover, contact between the granular active material and the particle containing niobium oxide makes the granular active material physically fixed; accordingly, deterioration due to expansion and contraction of the active material which occur along with charge and discharge of the power storage device, such as powdering of the active material or its separation from the current collector, can be suppressed.
摘要:
One of objects is to reduce the effect caused by the volume expansion of an active material. An embodiment is a method for manufacturing an electrode for a power storage device which includes an active material over one of surfaces of a current collector. The active material is formed by forming a conductive body functioning as the current collector; forming a mixed layer including an amorphous region and a microcrystalline region over one of surfaces of the conductive body; and etching the mixed layer selectively, so that a part of or the whole of the amorphous region is removed and the microcrystalline region is exposed. Thus, the effect caused by the volume expansion of the active material is reduced.
摘要:
An electrode of an energy storage device with less deterioration by charge and discharge can be manufactured. In addition, an energy storage device which has large capacity and high endurance can be manufactured. A manufacturing method of an electrode of an energy storage device is provided in which a high-wettability regions and a low-wettability region are formed at a surface of a current collector, a composition containing silicon, germanium, or tin is discharged to the high-wettability regions and then baked to form separate active materials over a surface of the current collector. Thus, an electrode of an energy storage device with less deterioration due to charge and discharge can be manufactured.
摘要:
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.
摘要:
A single crystal semiconductor layer is formed over a substrate having an insulating surface by the following steps: forming an ion doped layer at a given depth from a surface of a single crystal semiconductor substrate; performing plasma treatment to the surface of the single crystal semiconductor substrate; forming an insulating layer on the single crystal semiconductor substrate to which the plasma treatment is performed; bonding the single crystal semiconductor substrate to the substrate having the insulating surface with an insulating layer interposed therebetween; and separating the single crystal semiconductor substrate using the ion doped layer as a separation surface. As a result, a semiconductor substrate in which a defect in an interface between the single crystal semiconductor layer and the insulating layer is reduced can be provided.
摘要:
A power storage device which has improved performance such as higher discharge capacity and in which deterioration due to peeling or the like of an active material layer is less likely to be caused is provided. In an electrode for the power storage device, phosphorus-doped amorphous silicon is used for the active material layer over a current collector as a material that can be alloyed with lithium, and niobium oxide is deposited over the active material layer as a layer containing niobium. Accordingly, the capacity of the power storage device can be increased and the cycle characteristics and the charge-discharge efficiency can be improved.
摘要:
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.
摘要:
To provide a method of obtaining a single crystal semiconductor film by a method that is simple and low-cost. A single crystal semiconductor film 11 having compression stress is formed over a surface of a single crystal semiconductor substrate 10 by a vapor phase epitaxial growth method, a film having tensile stress (for example, a thermo-setting resin film 12) is formed over a surface of the single crystal semiconductor film 11, and the single crystal semiconductor substrate 10 and the single crystal semiconductor film 11 are separated from each other by a separation step in which force is applied to the single crystal semiconductor film 11, thereby obtaining a single crystal semiconductor film. Note that as the thermo-setting resin film 12, an epoxy resin film can be used, for example.
摘要:
A secondary battery to be provided includes an electrode including silicon or a silicon compound, and the electrode includes, for example, a current collector formed using metal and a silicon film as an active material provided over the current collector. The hydrogen concentration in the silicon film of the electrode may be higher than or equal to 1.0×1018 cm−3 and lower than or equal to 1.0×1021 cm−3. Such a silicon film is formed over a current collector by a plasma CVD method or the like for example, and hydrogen is contained as little as possible in the silicon film, which is preferable. In order to contain hydrogen as little as possible in the silicon film, the silicon film may be formed over the current collector under a high temperature environment.
摘要:
A single crystal semiconductor layer is formed over a substrate having an insulating surface by the following steps: forming an ion doped layer at a given depth from a surface of a single crystal semiconductor substrate; performing plasma treatment to the surface of the single crystal semiconductor substrate; forming an insulating layer on the single crystal semiconductor substrate to which the plasma treatment is performed; bonding the single crystal semiconductor substrate to the substrate having the insulating surface with an insulating layer interposed therebetween; and separating the single crystal semiconductor substrate using the ion doped layer as a separation surface. As a result, a semiconductor substrate in which a defect in an interface between the single crystal semiconductor layer and the insulating layer is reduced can be provided.