The reliability of a semiconductor device is increased by suppression of a variation in electric characteristics of a transistor as much as possible. As a cause of a variation in electric characteristics of a transistor including an oxide semiconductor, the concentration of hydrogen in the oxide semiconductor, the density of oxygen vacancies in the oxide semiconductor, or the like can be given. A source electrode and a drain electrode are formed using a conductive material which is easily bonded to oxygen. A channel formation region is formed using an oxide layer formed by a sputtering method or the like under an atmosphere containing oxygen. Thus, the concentration of hydrogen in a stack, in particular, the concentration of hydrogen in a channel formation region can be reduced.

A transistor manufacturing method includes: forming a first insulator layer of which formation material is a fluorine-containing resin, on a substrate having a source electrode, a drain electrode, and a semiconductor layer so as to cover the semiconductor layer; forming a second insulator layer to cover the first insulator layer; forming a base film on at least part of a surface of the second insulator layer; and after depositing a metal which is an electroless plating catalyst on a surface of the base film, forming a gate electrode on the surface of the base film by electroless plating, wherein the forming of the base film is performed by applying a liquid substance which is a formation material of the base film to the surface of the second insulator layer, and the second insulator layer has a higher lyophilic property with respect to the liquid substance than the first insulator layer.

A dual gate oxide semiconductor thin-film transistor (TFT) substrate includes a substrate; a bottom gate positioned on the substrate; a bottom gate isolation layer positioned on the substrate and the bottom gate; a first oxide semiconductor layer positioned on the bottom gate isolation layer above the bottom gate; an oxide conductor layer positioned on the bottom gate isolation layer at one side of the first oxide semiconductor layer; a top gate isolation layer positioned on the first oxide semiconductor layer, the oxide conductor layer, and the bottom gate isolation layer; a top gate positioned on the top gate isolation layer above a middle part of the first oxide semiconductor layer; a source and a drain positioned on the top gate isolation layer at two sides of the top gate; and a passivation layer positioned on the top gate isolation layer, the source, the drain, and the top gate.

Provided are liquid crystal display and the method for manufacturing the same. According to an aspect of the present disclosure, there is provided a liquid crystal display device, including: a first substrate; a gate electrode disposed on the first substrate; a semiconductor pattern layer disposed on the gate electrode; and a source electrode and a drain electrode disposed on the semiconductor pattern layer and facing each other, wherein the gate electrode includes a reference plane and a protrusion protruding from the reference plane in a horizontal direction, and the protrusion overlaps the source electrode and the drain electrode.

In a semiconductor device, a first interlayer insulating layer made of an inorganic material and formed on inverse stagger type TFTs, a second interlayer insulating layer made of an organic material and formed on the first interlayer insulating layer, and a pixel electrode formed in contact with the second interlayer insulating layer are disposed on a substrate, and an input terminal portion that is electrically connected to a wiring of another substrate is provided on an end portion of the substrate. The input terminal portion includes a first layer made of the same material as that of the gate electrode and a second layer made of the same material as that of the pixel electrode. With this structure, the number of photomasks used in the photolithography method can be reduced to 5.

An object is to provide a deposition method in which a gallium oxide film is formed by a DC sputtering method. Another object is to provide a method for manufacturing a semiconductor device using a gallium oxide film as an insulating layer such as a gate insulating layer of a transistor. An insulating film is formed by a DC sputtering method or a pulsed DC sputtering method, using an oxide target including gallium oxide (also referred to as GaO.sub.X). The oxide target includes GaO.sub.X, and X is less than 1.5, preferably more than or equal to 0.01 and less than or equal to 0.5, further preferably more than or equal to 0.1 and less than or equal to 0.2. The oxide target has conductivity, and sputtering is performed in an oxygen gas atmosphere or a mixed atmosphere of an oxygen gas and a rare gas such as argon.

It is an object to manufacture a highly reliable display device using a thin film transistor having favorable electric characteristics and high reliability as a switching element. In a bottom gate thin film transistor including an amorphous oxide semiconductor, an oxide conductive layer having a crystal region is formed between an oxide semiconductor layer which has been dehydrated or dehydrogenated by heat treatment and each of a source electrode layer and a drain electrode layer which are formed using a metal material. Accordingly, contact resistance between the oxide semiconductor layer and each of the source electrode layer and the drain electrode layer can be reduced; thus, a thin film transistor having favorable electric characteristics and a highly reliable display device using the thin film transistor can be provided.

A transistor with stable electrical characteristics is provided. The transistor includes a first insulator over a substrate; first to third oxide insulators over the first insulator; a second insulator over the third oxide insulator; a first conductor over the second insulator; and a third insulator over the first conductor. An energy level of a conduction band minimum of each of the first and second oxide insulators is closer to a vacuum level than that of the oxide semiconductor is. An energy level of a conduction band minimum of the third oxide insulator is closer to the vacuum level than that of the second oxide insulator is. The first insulator contains oxygen. The number of oxygen molecules released from the first insulator measured by thermal desorption spectroscopy is greater than or equal to 1E14 molecules/cm.sup.2 and less than or equal to 1E16 molecules/cm.sup.2.

The present invention provides a manufacture method of a LTPS thin film transistor and a LTPS thin film transistor. The gate isolation layer is first etched to form the recess, and then the gate is formed on the recess so that the width of the gate is slightly larger than the width of the recess. Then, the active layer is implemented with ion implantation to form the source contact region, the drain contact region, the channel region and one transition region at least located between the drain contact region and the channel region. The gate isolation layer above the transition region is thicker than the channel region and can shield a part of the gate electrical field to make the carrier density here lower than the channel region to form a transition.

A method and apparatus for use in improving linearity sensitivity of MOSFET devices having an accumulated charge sink (ACS) are disclosed. The method and apparatus are adapted to address degradation in second- and third-order intermodulation harmonic distortion at a desired range of operating voltage in devices employing an accumulated charge sink.