An object is to provide a semiconductor device of which a manufacturing process is not complicated and by which cost can be suppressed, by forming a thin film transistor using an oxide semiconductor film typified by zinc oxide, and a manufacturing method thereof. For the semiconductor device, a gate electrode is formed over a substrate; a gate insulating film is formed covering the gate electrode; an oxide semiconductor film is formed over the gate insulating film; and a first conductive film and a second conductive film are formed over the oxide semiconductor film. The oxide semiconductor film has at least a crystallized region in a channel region.

Semiconductor device, and manufacturing method thereof

The subject of the invention is a glass-, ceramic- or vitroceramic-based substrate (1) provided on at least part of at least one of its faces with a coating (3) with a photocatalytic property containing at least partially crystalline titanium oxide. It also relates to the applications of such a substrate and to its method of preparation.

Substrate with a photocatalytic coating

Tunnel oxide passivated contacts as an alternative to partial rear contacts

Tunnel oxide passivated carrier-selective contacts based on ultra-thin SiO2 layers

Carrier transport characteristics in high-efficiency single-walled carbon nanotubes (SWNTs)/silicon (Si) hybrid solar cells are presented. The solar cells were fabricated by depositing intrinsic p-type SWNT thin-films on n-type Si wafers without involving any high-temperature process for p–n junction formation. The optimized cells showed a device ideality factor close to unity and a record-high power-conversion-efficiency of >11%. By investigating the dark forward current density characteristics with varying temperature, we have identified that the temperature-dependent current rectification originates from the thermally activated band-to-band transition of carriers in Si, and the role of the SWNT thin films is to establish a built-in potential for carrier separation/collection. We have also established that the dominant carrier transport mechanism is diffusion, with minimal interface recombination. This is further supported by the observation of a long minority carrier lifetime of ∼34 μs, determined by t...

Record High Efficiency Single-Walled Carbon Nanotube/Silicon p-n Junction Solar Cells

Ultrathin silicon dioxide (SiO2) layers with excellent electrical characteristics can be formed using the nitric acid oxidation of Si (NAOS) method, i.e., by immersion of Si in nitric acid (HNO3) solutions. The SiO2 layer formed with 61 wt % HNO3 at its boiling temperature of 113 °C has a 1.3 nm thickness with a considerably high density leakage current. When the SiO2 layer is formed in 68 wt % HNO3 (i.e., azeotropic mixture with water), on the other hand, the leakage current density (e.g., 1.5 A/cm2 at the forward gate bias, VG, of 1 V) becomes as low as that of thermally grown SiO2 layers, in spite of the nearly identical SiO2 thickness of 1.4 nm. Due to the relatively low leakage current density of the NAOS oxide layer, capacitance–voltage (C–V) curves can be measured in spite of the ultrathin oxide thickness. However, a hump is present in the C–V curve, indicating the presence of high-density interface states. Fourier transformed infrared absorption measurements show that the atomic density of the SiO...

Nitric acid oxidation of Si to form ultrathin silicon dioxide layers with a low leakage current density

There are provided image pickup devices capable of significantly increasing production yield and ensuring long-term reliability and a method for manufacturing the image pickup devices. This invention is characterized in that it has a large number of light-receiving portions 2 formed at a surface portion of a wafer 1 and a microlens 3 formed for each of the light-receiving portions, through electrodes 4 for performing supply of power to the light-receiving portions 2 and passing and reception of an electrical signal are provided all over the periphery of the wafer 1 , one end of each through electrode 4 is connected to an electrode pad 4 a which is connected to a wire leading to a light-receiving element at the surface portion of the wafer 1 , the other end is connected to a wire through a back electrode 5 , a rib 7 which serves as a partition portion arranged to surround the microlenses 3 on four sides is provided on the surface of the wafer 1 , a transparent plate 8 of optical glass or the like is bonded to an upper surface of the rib 7 with adhesive, and a protective frame 10 is provided at a junction between the rib 7 and the transparent plate 8.

Solid-Stated Image Pickup Device And Method For Manufacturing Same

Spectroscopic and electrical properties of ultrathin SiO2 layers formed with nitric acid

In the study of electroless Ni plating of Si wafers with p‐n junctions using conventional solutions, a pronounced difference in plating rate between p‐ and n‐type surfaces is observed. Further experiments show that rate difference probably should not only be attributed to the photovoltaic effect generated at the p‐n junctions but also to the electronegativity difference between p‐ and n‐type Si. The latter effect can be changed by addition of such material as or to the plating solution. Whereas addition increases the rate difference, EDTA addition decreases it. This fact which can be put to practical use gives an extra support for the explanation given above.

https://iopscience.iop.org/article/10.1149/1.2411283/pdf

Hitoo Iwasa

Papers

Nitric acid oxidation of Si to form ultrathin silicon dioxide layers with a low leakage current density

Solid-Stated Image Pickup Device And Method For Manufacturing Same

Spectroscopic and electrical properties of ultrathin SiO2 layers formed with nitric acid

Electroless Nickel Plating on Silicon

Experimental and theoretical studies of Si–CN bonds to eliminate interface states at Si/SiO2 interface