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

An object is to provide a method for manufacturing a semiconductor device, in which the number of photolithography steps can be reduced, the manufacturing process can be simplified, and manufacturing can be performed with high yield at low cost A method for manufacturing a semiconductor device includes the following steps: forming a semiconductor film; irradiating a laser beam by passing the laser beam through a photomask including a shield for shielding the laser beam; subliming a region which has been irradiated with the laser beam through a region in which the shield is not formed in the photomask in the semiconductor film; forming an island-shaped semiconductor film in such a way that a region which is not irradiated with the laser beam is not sublimed because it is a region in which the shield is formed in the photomask; forming a first electrode which is one of a source electrode and a drain electrode and a second electrode which is the other one of the source electrode and the drain electrode; forming a gate insulating film; and forming a gate electrode over the gate insulating film

Method for Manufacturing Semiconductor Device

A nonplanar semiconductor device and its method of fabrication is described. The nonplanar semiconductor device includes a semiconductor body having a top surface opposite a bottom surface formed above an insulating substrate wherein the semiconductor body has a pair laterally opposite sidewalls. A gate dielectric is formed on the top surface of the semiconductor body on the laterally opposite sidewalls of the semiconductor body and on at least a portion of the bottom surface of semiconductor body. A gate electrode is formed on the gate dielectric, on the top surface of the semiconductor body and adjacent to the gate dielectric on the laterally opposite sidewalls of semiconductor body and beneath the gate dielectric on the bottom surface of the semiconductor body. A pair source/drain regions are formed in the semiconductor body on opposite sides of the gate electrode.

Nonplanar semiconductor device with partially or fully wrapped around gate electrode and methods of fabrication

A method of a bulk tri-gate transistor having stained enhanced mobility and its method of fabrication. The present invention is a nonplanar transistor having a strained enhanced mobility and its method of fabrication. The transistor has a semiconductor body formed on a semiconductor substrate wherein the semiconductor body has a top surface on laterally opposite sidewalls. A semiconductor capping layer is formed on the top surface and on the sidewalls of the semiconductor body. A gate dielectric layer is formed on the semiconductor capping layer on the top surface of a semiconductor body and is formed on the capping layer on the sidewalls of the semiconductor body. A gate electrode having a pair of laterally opposite sidewalls is formed on and around the gate dielectric layer. A pair of source/drain regions are formed in the semiconductor body on opposite sides of the gate electrode.

Bulk non-planar transistor having strained enhanced mobility and methods of fabrication

https://ir.nctu.edu.tw:443/bitstream/11536/30330/1/000087849500001.pdf

Progress in the developments of (Ba,Sr)TiO3 (BST) thin films for Gigabit era DRAMs

A dummy gate electrode is formed before the gate electrode is formed. Extension regions, side wall silicon nitride film, source/drain regions, silicon oxide film, and others are formed with respect to the dummy gate electrode. The dummy gate electrode is removed, and a part of the extension regions diffused to a region immediately under the dummy gate electrode is removed. The removed part is filled with silicon selection epitaxial film. Thereafter, the intended gate electrode is formed. This production method gives a semiconductor device that prevents the deterioration of electrical characteristics caused by short channel effect and parasitic resistance.

Semiconductor device and method of producing the same

Enhanced performance of RF power modules is required in a next-generation information society. To satisfy these requirements, we designed a novel high-electron mobility transistor (HEMT) structure employing wider bandgap AlGaN for a channel layer, which we called AlGaN channel HEMT, and investigated it. The wider bandgap is more effective for higher voltage operation of HEMTs and contributes to the increase of output power in RF power modules. As a result, fabricated AlGaN channel HEMTs had much higher breakdown voltages than those of conventional GaN channel HEMTs with good pinchoff operation and sufficiently high drain current density without noticeable current collapse. Furthermore, specific on-state resistances of fabricated AlGaN channel HEMTs were competitive with the best values of reported GaN- and SiC-based devices with similar breakdown voltages. These results indicate that the proposed AlGaN channel HEMTs are very promising not only for an information-communication society but also in the power electronics field.

AlGaN Channel HEMT With Extremely High Breakdown Voltage

A thin film forming apparatus using laser includes a chamber (1), a target (5) placed therein, a laser light source (10) for emitting laser beam to target (5), and a substrate holder (3). When target (5) is irradiated with laser beam (16), a plume (15) is generated, and materials included in plume (15) are deposited on the surface of a substrate (2) held by substrate holder (3). The laser beam emitted from laser light source (10) has its cross section shaped to a desired shape when passed through a shielding plate (4804), for example, so that the surface of the target (5) is irradiated with the beam having uniform light intensity distribution. Therefore, a plume (15) having uniform density distribution of active particles is generated, and therefore a thin film of high quality can be formed over a wide area with uniform film quality, without damaging the substrate.

Thin film forming apparatus using laser

The gate length (L) dependence of the isolation edge effect is investigated for MOSFETs with various isolation structures We extract the isolation edge effect for a single L by comparing with an H-shaped gate MOSFET which did not have any influence from the isolation edges For shallow trench isolation (STI), the isolation edge effect is enhanced for L around the onset of the short channel effect (SCE) and is more prominent for a trench edge with a deeper dip On the other hand, for the local oxidation of silicon (LOCOS) isolation with an elevated field oxide edge (ie, the bird's beak), the isolation edge effect operates in the opposite direction against the cases of STI, though it is enhanced around the SCE appearance point The L dependence is successfully explained using the charge sharing model where the charge shared by the mixing effect between the SCE and the (inverse) narrow width effect [(I)NWE] is introduced at the channel corners The enhancement of the isolation edge effect results from that the fraction of the charge shared by the mixing effect depends on L In addition, the difference between STI and LOCOS occurs because the mixing effect for STI is opposite to that for LOCOS

Isolation edge effect depending on gate length of MOSFETs with various isolation structures

Schottky diodes with Ni-Ti-Pt-Au Schottky electrodes on AlGaN-GaN heterostructures were fabricated and subjected to rapid thermal annealing. The electrical influence on them was investigated in terms of the existence of a thin Ni or Ti layer. The diodes of the Ni-Pt-Au system showed a drastic improvement in their electrical properties, such as an increase in the Schottky barrier height and a decrease in the leakage current, after the 600/spl deg/C treatment whereas the thermal annealing effect was found to be small in the Ti-Pt-Au and the Pt-Au systems. The Ni was considered to play a significant role in realizing a clean Pt contact to AlGaN and reducing surface traps, which were revealed from Auger electron spectroscopy measurement and frequency-dependent capacitance-voltage measurement, respectively. The thermally-treated Ni-Pt-Au gate electrode was concluded to be practicable for realizing high performance HEMTs.

Toshiyuki Oishi

Papers

Semiconductor device and method of producing the same

AlGaN Channel HEMT With Extremely High Breakdown Voltage

Thin film forming apparatus using laser

Isolation edge effect depending on gate length of MOSFETs with various isolation structures

Effects of interfacial thin metal layer for high-performance Pt-Au-based Schottky contacts to AlGaN-GaN