Abstract: An ion implanted region is formed by implanting Mg ions into a predetermined region of the surface of the first p-type layer. Subsequently, a second n-type layer is formed on the first p-type layer and the ion implanted region. A trench is formed by dry etching a predetermined region of the surface of the second n-type layer until reaching the first n-type layer. Next, heat treatment is performed to diffuse Mg. Thus, a p-type impurity region is formed in a region with a predetermined depth from the surface of the first n-type layer below the ion implanted region. Since the trench is formed before the heat treatment, Mg is not diffused laterally beyond the trench. Therefore, the width of the p-type impurity region is almost the same as the width of the first p-type layer divided by the trench.

Abstract: An ion implanted region is formed by implanting Mg ions into a predetermined region of the surface of the first p-type layer. Subsequently, a second n-type layer is formed on the first p-type layer and the ion implanted region. A trench is formed by dry etching a predetermined region of the surface of the second n-type layer until reaching the first n-type layer. Next, heat treatment is performed to diffuse Mg. Thus, a p-type impurity region is formed in a region with a predetermined depth from the surface of the first n-type layer below the ion implanted region. Since the trench is formed before the heat treatment, Mg is not diffused laterally beyond the trench. Therefore, the width of the p-type impurity region is almost the same as the width of the first p-type layer divided by the trench.

Abstract: The likelihood of formation of a corner resulting from a recess in a part of an n-type semiconductor layer is reduced at a deeper position than a p-type semiconductor layer. A method of manufacturing a semiconductor device comprises: forming a gallium nitride (GaN) based n-type semiconductor layer containing n-type impurities; forming a groove by forming a first mask on a part of a surface of the n-type semiconductor layer and then etching a part uncovered by the first mask; removing the first mask; forming a gallium nitride (GaN) based p-type semiconductor layer containing p-type impurities on the surface of the n-type semiconductor layer including the groove; etching the p-type semiconductor layer so as to expose the n-type semiconductor layer at least in a range differing from a range in the presence of the groove; and forming a metal electrode contacting the exposed n-type semiconductor layer and the p-type semiconductor layer.

Abstract: An n-type GaN layer, a p-type diffusion region formed by ion implantation and annealing in a part of the n-type layer, and a Schottky electrode are formed on the n-type layer. A region without the p-type region is defined as region A, and a region with the p-type region is defined as region B. In region A, an average density of each electron trap level of the n-type layer in a region having a depth of 0.8 ?m to 1.6 ?m on the n-type layer side is set so as to satisfy the predetermined conditions. In region B, an average density of each carrier trap level of the n-type layer in a region having a depth of 0.8 ?m to 1.6 ?m on the n-type layer side from a boundary between the n-type layer and the p-type diffusion region is set so as to satisfy the predetermined conditions.

Abstract: A manufacturing method of a semiconductor device comprises forming an ohmic electrode on a surface of a semiconductor substrate, the ohmic electrode including an aluminum layer in a side opposite to a side in contact with the semiconductor substrate, performing a heat treatment on the ohmic electrode, performing an acid treatment on a surface of the aluminum layer in the ohmic electrode that has been subjected to the heat treatment and forming a wiring electrode in the side of the aluminum layer opposite to the side where the semiconductor substrate is provided after the acid treatment.

Abstract: The likelihood of formation of a corner resulting from a recess in a part of an n-type semiconductor layer is reduced at a deeper position than a p-type semiconductor layer. A method of manufacturing a semiconductor device comprises: forming a gallium nitride (GaN) based n-type semiconductor layer containing n-type impurities; forming a groove by forming a first mask on a part of a surface of the n-type semiconductor layer and then etching a part uncovered by the first mask; removing the first mask; forming a gallium nitride (GaN) based p-type semiconductor layer containing p-type impurities on the surface of the n-type semiconductor layer including the groove; etching the p-type semiconductor layer so as to expose the n-type semiconductor layer at least in a range differing from a range in the presence of the groove; and forming a metal electrode contacting the exposed n-type semiconductor layer and the p-type semiconductor layer.

Abstract: An n-type GaN layer, a p-type diffusion region formed by ion implantation and annealing in a part of the n-type layer, and a Schottky electrode are formed on the n-type layer. A region without the p-type region is defined as region A, and a region with the p-type region is defined as region B. In region A, an average density of each electron trap level of the n-type layer in a region having a depth of 0.8 ?m to 1.6 ?m on the n-type layer side is set so as to satisfy the predetermined conditions. In region B, an average density of each carrier trap level of the n-type layer in a region having a depth of 0.8 ?m to 1.6 ?m on the n-type layer side from a boundary between the n-type layer and the p-type diffusion region is set so as to satisfy the predetermined conditions.

Abstract: A manufacturing method of a semiconductor device comprises forming an ohmic electrode on a surface of a semiconductor substrate, the ohmic electrode including an aluminum layer in a side opposite to a side in contact with the semiconductor substrate, performing a heat treatment on the ohmic electrode, performing an acid treatment on a surface of the aluminum layer in the ohmic electrode that has been subjected to the heat treatment and forming a wiring electrode in the side of the aluminum layer opposite to the side where the semiconductor substrate is provided after the acid treatment.

Abstract: A technique of reducing the contact resistance between a semiconductor substrate and a metal layer is provided. A manufacturing method of a semiconductor device comprises a process of forming a metal layer on an N surface of a nitride semiconductor substrate. The process of forming the metal layer includes a first process of forming a metal layer by sputtering at a film formation rate controlled to 4 nm/minute or lower.

Abstract: A technique of reducing the contact resistance between a semiconductor substrate and a metal layer is provided. A manufacturing method of a semiconductor device comprises a process of forming a metal layer on an N surface of a nitride semiconductor substrate. The process of forming the metal layer includes a first process of forming a metal layer by sputtering at a film formation rate controlled to 4 nm/minute or lower.