A ceramic circuit substrate according to an embodiment includes a ceramic substrate and multiple metal parts. The ceramic substrate includes a first surface. The multiple metal parts are located respectively in multiple first regions of the first surface. The first surface includes a second region positioned between adjacent first regions of the multiple metal parts. An average length RSm of roughness curve elements in the second region is not less than 40 m. The average length RSm is preferably not more than 100 m. A maximum peak height Rp of a surface roughness curve in the second region is preferably not less than 1.0 m. A maximum valley depth Rv of a surface roughness curve in the second region is preferably not less than 1.0 m.

Semiconductor devices and methods for manufacturing the same are disclosed. In an embodiment, a method of manufacturing a semiconductor device may include providing a substrate having a recess; epitaxially forming a first layer including a doped semiconductor material within the recess; and epitaxially forming a second layer including an undoped semiconductor material over at least a portion of the recess.

Methods for forming semiconductor structures are provided. The method for forming the semiconductor structure includes forming a word line cell over a substrate and forming a dielectric layer over the word line cell. The method further includes forming a conductive layer over the dielectric layer and polishing the conductive layer until the dielectric layer is exposed. The method further includes forming an oxide layer on a top surface of the conductive layer and removing portions of the conductive layer not covered by the oxide layer to form a memory gate.

Techniques are disclosed for forming a GaN transistor on a semiconductor substrate. An insulating layer forms on top of a semiconductor substrate. A trench, filled with a trench material comprising a III-V semiconductor material, forms through the insulating layer and extends into the semiconductor substrate. A channel structure, containing III-V material having a defect density lower than the trench material, forms directly on top of the insulating layer and adjacent to the trench. A source and drain form on opposite sides of the channel structure, and a gate forms on the channel structure. The semiconductor substrate forms a plane upon which both GaN transistors and other transistors can form.

Impurity elements are doped at a high concentration exceeding a thermodynamic equilibrium concentration into a solid material having an extremely small diffusion coefficient of the impurity element. A method for doping impurities includes steps for depositing source film made of material containing impurity elements with a film thickness on a surface of a solid target object (semiconductor substrate) made from the solid material. The film thickness is determined in consideration of irradiation time per light pulse and the energy density of the light pulse. The method also includes a step for irradiating the source film by the light pulse with the irradiation time and the energy density so as to dope the impurity elements into the target object at a concentration exceeding a thermodynamic equilibrium concentration.

The present invention provides a semiconductor device, including a substrate, two gate structures disposed on a channel region of the substrate, an epitaxial layer disposed in the substrate between two gate structures, a first dislocation disposed in the epitaxial layer, wherein the profile of the first dislocation has at least two non-parallel slanting lines, and a second dislocation disposed adjacent to a top surface of the epitaxial layer, and the profile of the second dislocation has at least two non-parallel slanting lines.

A semiconductor substrate of an embodiment includes a SiC layer having a surface inclined in a <11-20> direction plus or minus 5 from a {0001} face at an off angle of 0 to 10. Area density of threading edge dislocation clusters in the SiC layer is 18.8 cm.sup.2 or less, each of the threading edge dislocation clusters includes a plurality of threading edge dislocations on the surface, the threading edge dislocations included in each of the threading edge dislocation clusters exist in a region that extends in a [1-100] direction plus or minus 5 and has a width of 30 m or less, each of the threading edge dislocation clusters includes at least three threading edge dislocations adjacent at an interval of 30 m or less, and an interval of adjacent threading edge dislocations in each of the threading edge dislocation clusters is 70 m or less.

A method of manufacturing a semiconductor device includes: forming a lattice defect layer in a substrate having a front surface region where a bipolar element of a pn junction type is formed and a rear surface region opposing the front surface region, the lattice defect layer being formed by injecting a charged particle to a first region in the rear surface region of the substrate; forming a laminated region, in which a first conductivity type impurity region and a second conductivity type impurity region are sequentially laminated from a rear surface side of the substrate toward the first region, in a second region in the rear surface region of the substrate, the first region being positioned deeper than the second region from a rear surface of the substrate; and selectively activating the laminated region by laser annealing after the formation of the laminated region and the lattice defect layer.

A method of manufacturing a semiconductor device includes forming a first plurality of recessed regions in a substrate, the substrate having a protruded active region between the first plurality of recessed regions and the protruded active region having an upper surface and a sidewall, forming a device isolation film in the first plurality of recessed regions, the device isolation film exposing the upper surface and an upper portion of the sidewall of the protruded active region, and performing a first plasma treatment on the exposed surface of the protruded active region, wherein the plasma treatment is performed using a plasma gas containing at least one of an inert gas and a hydrogen gas in a temperature of less than or equal to about 700 C.

A method for manufacturing a silicon carbide semiconductor device includes the following steps. A silicon carbide substrate is prepared. A first heating step of heating the silicon carbide substrate in an atmosphere of oxygen is performed. A second heating step of heating the silicon carbide substrate to a temperature of 1300 C. or more and 1500 C. or less in an atmosphere of gas containing nitrogen atoms or phosphorus atoms is performed after the first heating step. A third heating step of heating the silicon carbide substrate in an atmosphere of a first inert gas is performed after the second heating step. Thus, the silicon carbide semiconductor device in which threshold voltage variation is small, and a method for manufacturing the same can be provided.