摘要:
Methods are disclosed for forming a multi-layer structure including highly controlled diffusion interfaces between alternating layers of different semiconductor materials. According to embodiments, during a deposition of semiconductor layers, the process is controlled to remain at low temperatures such that an inter-diffusion rate between the materials of the deposited layers is managed to provide diffusion interfaces with abrupt Si/SiGe interfaces. The highly controlled interfaces and first and second layers provide a multi-layer structure with improved etching selectivity. In an embodiment, a gate all-around (GAA) transistor is formed with horizontal nanowires (NWs) from the multi-layer structure with improved etching selectivity. In embodiments, horizontal NWs of a GAA transistor may be formed with substantially the same size diameters and silicon germanium (SiGe) NWs may be formed with “all-in-one” silicon (Si) caps.
摘要:
A method for thermally processing a substrate having a surface region and a buried region with a pulsed light beam, the substrate presenting an initial temperature-depth profile and the surface region presenting an initial surface temperature, including steps of: illuminating the surface region with a preliminary pulse so that it generates an amount of heat and reaches a predetermined preliminary surface temperature; and illuminating the surface region with a subsequent pulse after a time interval so that it reaches a predetermined subsequent surface temperature. The time interval is determined such that the surface region reaches a predetermined intermediate surface temperature greater than the initial surface temperature, such that during the time interval, the amount of heat is diffused within the substrate down to a predetermined depth so that the substrate presents a predetermined intermediate temperature-depth profile.
摘要:
In a general aspect, an apparatus can include a silicon carbide (SiC) trench gate MOSFET with improved operation due, at least in part, to a reduced gate capacitance. In the SiC trench gate MOSFET, a thick gate oxide can be formed on a bottom surface of the gate trench and a built-in channel, having a vertical portion and a lateral portion, can be formed to electrically connect a vertical inversion-layer channel, such as in a channel stopper layer, to a vertical JFET channel region and a drift region.
摘要:
A method for manufacturing a silicon carbide semiconductor device includes the steps of preparing a silicon carbide substrate having a first main surface and a second main surface located on a side opposite to the first main surface, forming an epitaxial layer on the first main surface, the epitaxial layer having a first conductivity type and having a third main surface located on a side opposite to a side on which the silicon carbide substrate is located, forming a trench, which includes side walls intersecting with the third main surface and a bottom portion connected to the side walls, in the epitaxial layer, widening an opening of the trench, and forming an embedded region, which has a second conductivity type different from the first conductivity type, in the trench. The epitaxial layer adjacent to the embedded region and the embedded region constitute a superjunction structure.
摘要:
Methods for preparing layered semiconductor structures are disclosed. The methods may involve pretreating an ion-implanted donor wafer by annealing the ion-implanted donor wafer to cause a portion of the ions to out-diffuse prior to wafer bonding. The donor structure may be bonded to a handle structure and cleaved without re-implanting ions into the donor structure.
摘要:
A method for manufacturing a SiC semiconductor device includes the steps of: forming an impurity region in a SiC layer; forming a first carbon layer on a surface of the SiC layer having the impurity region formed therein, by selectively removing silicon from the surface; forming a second carbon layer on the first carbon layer; and heating the SiC layer having the first carbon layer and the second carbon layer formed therein.
摘要:
A method for processing a semiconductor includes irradiating a surface of a semiconductor with ions of a first gas type for cleaning the surface and implanting of ions of a second gas type in a region below the surface of the semiconductor for creating defects in the region below the surface. The irradiating and the implanting are performed within the same chamber.
摘要:
In a method for producing an SiC semiconductor device, a p type layer is formed in a trench by epitaxially growing, and is then left only on a bottom portion and ends of the trench by hydrogen etching, thereby to form a p type SiC layer. Thus, the p type SiC layer can be formed without depending on diagonal ion implantation. Since it is not necessary to separately perform the diagonal ion implantation, it is less likely that a production process will be complicated due to transferring into an ion implantation apparatus, and thus manufacturing costs reduce. Since there is no damage due to a defect caused by the ion implantation, it is possible to reduce a drain leakage and to reliably restrict the p type SiC layer from remaining on the side surface of the trench.
摘要:
A method for introducing impurity into a semiconductor substrate includes bringing a solution containing a compound of an impurity element into contact with a primary surface of a semiconductor substrate; and irradiating the primary surface of the semiconductor substrate with a laser beam through the solution to raise a temperature of the primary surface of the semiconductor substrate at a position irradiated by the laser beam so as to dope the impurity element into the semiconductor substrate. The laser beam irradiation is performed such that the raised temperature does not return to room temperature until a prescribed dose of the impurity element is caused to be doped into the semiconductor substrate.
摘要:
The present inventive concept has been made in an effort to improve the breakdown voltage of a silicon carbide MOSFET using a trench gate.A semiconductor device according to the present inventive concept includes a p type pillar region disposed below the trench, spaced apart from the trench or a first p type pillar region and a second p type pillar region disposed below the trench and corresponding to two corners of the trench.