An oxide semiconductor film having high stability with respect to light irradiation or a semiconductor device having high stability with respect to light irradiation is provided. One embodiment of the present invention is a semiconductor film including an oxide in which light absorption is observed by a constant photocurrent method (CPM) in a wavelength range of 400 nm to 800 nm, and in which an absorption coefficient of a defect level, which is obtained by removing light absorption due to a band tail from the light absorption, is lower than or equal to 5×10.sup.−2/cm. Alternatively, a semiconductor device is manufactured using the semiconductor film.

The semiconductor device includes a first insulator over a substrate, a first oxide semiconductor over the first insulator, a second oxide semiconductor over the first oxide semiconductor, a first conductor and a second conductor in contact with the second oxide semiconductor, a third oxide semiconductor on the second oxide semiconductor and the first and second conductors, a second insulator over the third oxide semiconductor, and a third conductor over the second insulator. At least one of the first oxide semiconductor, the second oxide semiconductor, and the third oxide semiconductor has a crystallinity peak that corresponds to a (hkl) plane (h=0, k=0, l is a natural number) observed by X-ray diffraction using a Cu K-alpha radiation as a radiation source. The peak appears at a diffraction angle 2 theta greater than or equal to 31.3 degrees and less than 33.5 degrees.

The present invention provides a fabrication method of an oxide semiconductor thin film and a fabrication method of a thin film transistor, belongs to the field of display technology, and can solve the problem of high crystallization temperature and high difficulty in fabrication process of an oxide semiconductor thin film in the existing oxide thin film transistor. The fabrication method of an oxide semiconductor thin film of the present invention includes: forming an induction layer thin film on a substrate; and forming an oxide semiconductor thin film on the substrate formed with the induction layer thin film, and performing an annealing process on the oxide semiconductor thin film to crystallize the oxide semiconductor thin film.

A method for filling a gap feature on a substrate surface is disclosed. The method may include: providing a substrate comprising a non-planar surface including one or more gap features; depositing a metal oxide film over a surface of the one or more gap features by a cyclical deposition process; contacting the metal oxide with an organic ligand vapor; and converting at least a portion of the metal oxide film to a porous material thereby filling the one or more gap features. Semiconductor structures including a metal-organic framework material formed by the methods of the disclosure are also disclosed.

An object is to provide a high reliability thin film transistor using an oxide semiconductor layer which has stable electric characteristics. In the thin film transistor in which an oxide semiconductor layer is used, the amount of change in threshold voltage of the thin film transistor before and after a BT test is made to be 2 V or less, preferably 1.5 V or less, more preferably 1 V or less, whereby the semiconductor device which has high reliability and stable electric characteristics can be manufactured. In particular, in a display device which is one embodiment of the semiconductor device, a malfunction such as display unevenness due to change in threshold voltage can be reduced.

A method for fabricating a metal oxide thin film transistor comprises selecting a substrate and fabricating a gate electrode thereon; growing a layer of dielectric or high permittivity dielectric on the substrate to serve as a gate dielectric layer; growing a first metal layer on the gate dielectric layer and a second metal layer on the first metal layer; fabricating a channel region at a middle position of the first metal layer and a passivation region at a middle position of the second metal layer; anodizing the metals of the passivation region and the channel region at atmospheric pressure and room temperature; fabricating a source and a drain; forming an active region comprising the source, the drain, and the channel region; depositing a silicon nitride layer on the active region; fabricating two electrode contact holes; depositing a metal aluminum film; and fabricating two metal contact electrodes by photolithography and etching.

A manufacturing method forms an oxide insulating layer and a first plasma etching treatment forms a depressed portion therein. A second plasma etching treatment forms a trench including curved lower corner portions. An oxide semiconductor film is formed in contact with a bottom portion, the curved lower corner portions, and side portions of the trench. Source and electrodes are formed to be electrically connected to the oxide semiconductor film. A gate insulating layer is formed over the oxide semiconductor film and a gate electrode is formed over the gate insulating layer. The first plasma etching treatment is performed with a first bias power and a first power of a first power source, and the second plasma etching treatment is performed with a second bias power and a second power of a second power source, wherein the second bias power is lower than the first bias power.

Provided are an oxide semiconductor layer in which the number of defects is reduced and a highly reliable semiconductor device including the oxide semiconductor. A first oxide semiconductor layer having a crystal part is formed over a substrate by a sputtering method. A second oxide semiconductor layer is formed by a thermal chemical vapor deposition method over the first oxide semiconductor layer. The second oxide semiconductor layer is formed by epitaxial growth using the first oxide semiconductor layer as a seed crystal. A channel is formed in the second oxide semiconductor layer.

The present invention provides a method to manufacture nanowires. In various embodiments, a method is provided for producing an oxidized metal layer as a heterogeneous seed layer on arbitrary substrate for controlled nanowire growth is disclosed which comprises depositing a metal layer on a substrate, oxidizing the metal layer in air ambient or in oxidizing agent, and growing nanowires at low temperatures on oxidized metal layers on virtually any substrate.

An object is to provide a manufacturing method of a semiconductor device in which a defect in characteristics due to a crack occurring in a semiconductor device is reduced. Provision of a crack suppression layer formed of a metal film in the periphery of a semiconductor element makes it possible to suppress a crack occurring from the outer periphery of a substrate and reduce damage to the semiconductor element. In addition, even if the semiconductor device is subjected to physical forces from the outer periphery in separation and transposition steps, progression (growth) of a crack to the semiconductor device can be suppressed by the crack suppression layer.