A technique of reducing the manufacturing cost of a semiconductor device is provided, There is provided a method of manufacturing a semiconductor device comprising an ion implantation process of implanting at least one of magnesium and beryllium by ion implantation into a first semiconductor layer that is mainly formed from a group III nitride; and a heating process of heating the first semiconductor layer in an atmosphere that includes an anneal gas of at least one of magnesium and beryllium, after the ion implantation process,

A technique of improving the breakdown voltage of a semiconductor device is provided. There is provided a method of manufacturing a semiconductor device comprising a process of forming a p-type semiconductor layer that contains a p-type impurity and has a dislocation density of not higher than 1.0×10.sup.7 cm.sup.−2, on an n-type semiconductor layer that contains an n-type impurity and has a dislocation density of not higher than 1.0×10.sup.7 cm.sup.−2; an n-type semiconductor region forming process of forming an n-type semiconductor region in at least part of the p-type semiconductor layer by ion-implanting an n-type impurity into the p-type semiconductor layer and performing heat treatment to activate the ion-implanted n-type impurity; and a process of forming a trench that is recessed to pass through the p-type semiconductor layer and reach the n-type semiconductor layer. In the n-type semiconductor region forming process, a p-type impurity diffusion region in which the p-type impurity contained in the p-type semiconductor layer is diffused is formed in at least part of the n-type semiconductor layer that is located below the n-type semiconductor region.

A semiconductor device including a substrate, a plurality of III-nitride semiconductor layers, a source electrode, a gate electrode, a drain electrode, and a doped layer. The III-nitride semiconductor layers are disposed on the substrate. A two dimensional electron gas (2DEG) channel is formed in the III-nitride semiconductor layers. The source electrode, the gate electrode, and the drain electrode are disposed on the III-nitride semiconductor layers. The gate electrode is located between the source electrode and the drain electrode. The source electrode and the drain electrode are electrically connected to the 2DEG channel. A lateral direction is defined from the source electrode to the drain electrode. The doped layer is disposed between the gate electrode and the III-nitride semiconductor layers. The doped layer includes a plurality of dopants, and a concentration of the dopants varies along the lateral direction.

A technique of suppressing the potential crowding in the vicinity of the outer periphery of a bottom face of a trench without ion implantation of a p-type impurity is provided. A method of manufacturing a semiconductor device having a trench gate structure comprises an n-type semiconductor region forming process. In the n-type semiconductor region forming process, a p-type impurity diffusion region in which a p-type impurity contained in a p-type semiconductor layer is diffused is formed in at least part of an n-type semiconductor layer that is located below an n-type semiconductor region.

A semiconductor device includes a substrate having an upper surface layer of a second conduction type formed at an upper surface side, a drift layer of a first conduction type formed under the upper surface layer, a buffer layer of the first conduction type formed under the drift layer, and a lower surface layer of the second conduction type formed under the buffer layer, the buffer layer includes a plurality of upper buffer layers provided apart from each other, and a plurality of lower buffer layers provided apart from each other between the plurality of upper buffer layers and the lower surface layer, wherein the plurality of upper buffer layers are formed so that average impurity concentrations in first sections each extending from the upper end of one of the upper buffer layers to the next lower buffer layer are unified as a first concentration.

When a defect region is present near the pn junction in a GaN layer, lattice defects are present in the depletion layer. Therefore, when a reverse bias is applied to the pn junction, the defects in the depletion layer cause the generated current to flow as a leakage current. The leakage current flowing through the depletion layer can cause a decrease in the withstand voltage at the pn junction. Provided is a semiconductor device using gallium nitride, including a gallium nitride layer including an n-type region. The gallium nitride layer includes a first p-type well region and a second p-type well region that is provided on at least a portion of the first p-type well region and has a peak region with a higher p-type impurity concentration than the first p-type well region.

A fin field effect transistor (FinFET) device includes a substrate and a template material over the substrate. The template material absorbs lattice mismatches with the substrate. The FinFET device also includes a barrier material over the template material. The barrier material is free of point defects. The FinFET device further includes a channel material over the barrier material.

The present disclosure is related to a III-Nitride semiconductor device comprising a base substrate, a buffer layer, a channel layer, a barrier layer so that a 2-dimensional charge carrier gas is formed or can be formed near the interface between the channel layer and the barrier layer, and at least one set of a first and second electrode in electrical contact with the 2-dimensional charge carrier gas, wherein the device further comprises a mobile charge layer (MCL) within the buffer layer or near the interface between the buffer layer and the channel layer, when the device is in the on-state. The device further comprises an electrically conductive path between one of the electrodes and the mobile charge layer. The present disclosure is also related to a method for producing a device according to the present disclosure.

A technique of reducing the complication in manufacture is provided. There is provided a semiconductor device comprising an n-type semiconductor region made of a nitride semiconductor containing gallium; a p-type semiconductor region arranged to be adjacent to and in contact with the n-type semiconductor region and made of the nitride semiconductor; a first electrode arranged to be in ohmic contact with the n-type semiconductor region; and a second electrode arranged to be in ohmic contact with the p-type semiconductor region. The first electrode and the second electrode are mainly made of one identical metal. The identical metal is at least one metal selected from the group consisting of palladium, nickel and platinum. A concentration of a p-type impurity in the n-type semiconductor region is approximately equal to a concentration of the p-type impurity in the p-type semiconductor region. A difference between a concentration of an n-type impurity and the concentration of the p-type impurity in the n-type semiconductor region is not less than 1.0×10.sup.19 cm.sup.−3.

In certain examples, methods and semiconductor structures are directed to use of a doped buried region (e.g., Mg-dopant) including a III-Nitride material and having a diffusion path (“ion diffusion path”) that includes hydrogen introduced by using ion implantation via at least one ion species. An ion implantation thermal treatment causes hydrogen to diffuse through the ion implanted path and causes activation of the buried region. In more specific examples in which such semiconductor structures have an ohmic contact region at which a source of a transistor interfaces with the buried region, the ohmic contact region is without etching-based damage due at least in part to the post-ion implantation thermal treatment.