Abstract: A semiconductor device has an active layer, a first semiconductor layer of first conductive type, an overflow prevention layer disposed between the active layer and the first semiconductor layer, which is doped with impurities of first conductive type and which prevents overflow of electrons or holes, a second semiconductor layer of first conductive type disposed at least one of between the active layer and the overflow prevention layer and between the overflow prevention layer and the first semiconductor layer, and an impurity diffusion prevention layer disposed between the first semiconductor layer and the active layer, which has a band gap smaller than those of the overflow prevention layer, the first semiconductor layer and the second semiconductor layer and which prevents diffusion of impurities of first conductive type.

Abstract: According to one embodiment, a nitride semiconductor device includes a foundation layer, a first stacked intermediate layer, and a functional layer. The foundation layer includes an AlN buffer layer formed on a substrate. The first stacked intermediate layer is provided on the foundation layer. The first stacked intermediate layer includes a first AlN intermediate layer provided on the foundation layer, a first AlGaN intermediate layer provided on the first AlN intermediate layer, and a first GaN intermediate layer provided on the first AlGaN intermediate layer. The functional layer is provided on the first stacked intermediate layer. The first AlGaN intermediate layer includes a first step layer in contact with the first AlN intermediate layer. An Al composition ratio in the first step layer decreases stepwise in a stacking direction from the first AlN intermediate layer toward the first step layer.

Abstract: According to one embodiment, a wafer includes a substrate, a base layer, a foundation layer, an intermediate layer and a functional unit. The substrate has a major surface. The base layer is provided on the major surface and includes a silicon compound. The foundation layer is provided on the base layer and includes GaN. The intermediate layer is provided on the foundation layer and includes a layer including AlN. The functional unit is provided on the intermediate layer and includes a nitride semiconductor. The foundation layer has a first region on a side of the base layer, and a second region on a side of the intermediate layer. A concentration of silicon atoms in the first region is higher than a concentration of silicon atoms in the second region. The foundation layer has a plurality of voids provided in the first region.

Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure body, a first electrode, a second electrode, and a dielectric body part. The stacked structure body includes a first semiconductor layer, having a first portion and a second portion juxtaposed with the first portion, a light emitting layer provided on the second portion, a second semiconductor layer provided on the light emitting layer. The first electrode includes a contact part provided on the first portion and contacting the first layer. The second electrode includes a first part provided on the second semiconductor layer and contacting the second layer, and a second part electrically connected with the first part and including a portion overlapping with the contact part when viewed from the first layer toward the second layer. The dielectric body part is provided between the contact part and the second part.

Abstract: According to one embodiment, a semiconductor light-emitting device includes: a first conductivity type first semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in a (0001) surface; a second conductivity type second semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in the (0001) surface; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, containing a nitride semiconductor crystal, and having an average lattice constant larger than the lattice constant of the first semiconductor layer; and a first stress application layer provided on a side opposite to the light emitting layer of the first semiconductor layer and applying a compressive stress to the first semiconductor layer.

Abstract: According to one embodiment, a semiconductor light emitting element includes an n-type semiconductor layer including a nitride semiconductor, a p-type semiconductor layer and a light emitting layer. The p-type semiconductor layer includes a first p-side layer of Alx1Ga1?x1N (0?x1<1) including Mg, a second p-side layer of Alx2Ga1?x2N (0<x2<1) including Mg and a third p-side layer of Alx3Ga1?x3N (x2<x3<1) including Mg. The light emitting layer is provided between the n-type semiconductor layer and the second p-side layer. The light emitting layer includes barrier layers and well layers. Each of the well layers is provided between the barrier layers. A p-side barrier layer of the barrier layers most proximal to the second p-side layer includes a first layer of Alz1Ga1?z1N (0?z1), and a second layer of Alz2Ga1?z2N (z1<z2<x2).

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, and a light emitting layer. The p-type semiconductor layer includes a first p-side layer, a second p-side layer, and a third p-side layer. A concentration profile of Mg of a p-side region includes a first portion, a second portion, a third portion, a fourth portion, a fifth portion, a sixth portion and a seventh portion. The p-side region includes the light emitting layer, the second p-side layer, and the third p-side layer. A Mg concentration of the sixth portion is not less than 1×1020 cm?3 and not more than 3×1020 cm?3. The Al concentration is 1/100 of the maximum value at a second position. A Mg concentration at the second position is not less than 2×1018 cm?3.

Abstract: A semiconductor light emitting device has a light emitting element, a first electrode layer, a second electrode layer, a seed electrode layer and a plated layer. The light emitting element has a nitride-based III-V compound semiconductor on a substrate and a light extraction surface. The first electrode layer is provided on the light extraction surface. The second electrode layer is provided on a surface opposite to the light extraction surface. The seed electrode layer is configured to cover the entire surface of the second electrode layer. The plated layer is provided on the seed electrode layer. The light emitting element has a light emitting layer, first conductive type semiconductor layer, and second conductive type semiconductor layer, and has a forward tapered shape of a width which gradually narrows in order of the second conductive type semiconductor layer, the light emitting layer and the first conductive type semiconductor layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes a p-type semiconductor layer, an n-type semiconductor layer, a light emitting layer, a p-side electrode and an n-side electrode. The p-type semiconductor layer includes a nitride semiconductor and has a first major surface. The n-type semiconductor layer includes a nitride semiconductor and has a second major surface. The light emitting layer is provided between the n-type semiconductor layer and the p-type semiconductor layer. The p-side electrode contacts a part of the p-type semiconductor layer on the first major surface. The n-side electrode contacts a part of the n-type semiconductor layer on the second major surface. The n-side electrode is provided outside and around the p-side electrode in a plan view along a direction from the p-type semiconductor layer to the n-type semiconductor layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, first and second electrodes, a high resistance layer and a transparent conductive layer. The stacked structural body includes first and second semiconductor layers and a light emitting layer. The first semiconductor layer is disposed between the first electrode and the second semiconductor layer. The second semiconductor layer is disposed between the second electrode and the first semiconductor layer. The second electrode has reflectivity with respect to luminescent light. The high resistance layer is in contact with the second semiconductor layer between the second semiconductor layer and the second electrode and includes a portion overlapping with the first electrode. The transparent conductive layer is in contact with the second semiconductor layer between the second semiconductor layer and the second electrode.

Abstract: According to one embodiment, a nitride semiconductor device includes a foundation layer and a functional layer. The foundation layer is formed on an Al-containing nitride semiconductor layer formed on a silicon substrate. The foundation layer has a thickness not less than 1 micrometer and including GaN. The functional layer is provided on the foundation layer. The functional layer includes a first semiconductor layer. The first semiconductor layer has an impurity concentration higher than an impurity concentration in the foundation layer and includes GaN of a first conductivity type.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, and a light emitting part. The n-type semiconductor layer includes a nitride semiconductor. The p-type semiconductor layer includes a nitride semiconductor. The light emitting part is provided between the n-type and the p-type semiconductor layers and includes an n-side barrier layer and a first light emitting layer. The first light emitting layer includes a first barrier layer, a first well layer, and a first AIGaN layer. The first barrier layer is provided between the n-side barrier layer and the p-type semiconductor layer. The first well layer contacts the n-side barrier layer between the n-side and the first barrier layer. The first AIGaN layer is provided between the first well layer and the first barrier layer. A peak wavelength ?p of light emitted from the light emitting part is longer than 515 nanometers.

Abstract: According to one embodiment, a semiconductor light emitting device includes an electrode layer, a first semiconductor layer, a first elongated electrode, a second semiconductor layer, and a light emitting layer. The first semiconductor layer includes a crystal having a cleavage plane. The first semiconductor layer includes a first thin film portion and a thick film portion. The first thin film portion extends in a first direction perpendicular to a stacking direction from the electrode layer toward the first semiconductor layer. The first thin film portion has a first thickness. The thick film portion is arranged with the first thin film portion in a plane perpendicular to the stacking direction. An angle between the first direction and the cleavage plane is not less than 3 degrees and not more than 27 degrees. The first elongated electrode extends in the first direction in contact with the first thin film portion.

Abstract: A semiconductor device of an embodiment includes: a semiconductor layer made of p-type nitride semiconductor; an oxide layer formed on the semiconductor layer, the oxide layer being made of a crystalline nickel oxide, and the oxide layer having a thickness of 3 nm or less; and a metal layer formed on the oxide layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, a light emitting part, and a p-side electrode. The light emitting part is provided between the n-type and the p-type semiconductor layers, and includes a plurality of barrier layers and a plurality of well layers. The p-side electrode contacts the p-type semiconductor layer. The p-type semiconductor layer includes first, second, third, and fourth p-type layers. The first p-type layer contacts the p-side electrode. The second p-type layer contacts the light emitting part. The third p-type layer is provided between the first p-type layer and the second p-type layer. The fourth p-type layer is provided between the second p-type layer and the third p-type layer. The second p-type layer contains Al and contains a p-type impurity in a lower concentration lower than that in the first concentration.

Abstract: A semiconductor device has an active layer, a first semiconductor layer of first conductive type, an overflow prevention layer disposed between the active layer and the first semiconductor layer, which is doped with impurities of first conductive type and which prevents overflow of electrons or holes, a second semiconductor layer of first conductive type disposed at least one of between the active layer and the overflow prevention layer and between the overflow prevention layer and the first semiconductor layer, and an impurity diffusion prevention layer disposed between the first semiconductor layer and the active layer, which has a band gap smaller than those of the overflow prevention layer, the first semiconductor layer and the second semiconductor layer and which prevents diffusion of impurities of first conductive type.

Abstract: A semiconductor light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, and an active layer formed between the n-type semiconductor layer and the p-type semiconductor layer, and emitting light. The device further includes a p-electrode contacting to the p-type semiconductor layer, and including a first conductive oxide layer having an oxygen content lower than 40 atomic % and a second conductive oxide layer contacting to the first conductive oxide layer and having a higher oxygen content than the oxygen content of the first conductive oxide layer. The device also includes an n-electrode connecting electrically to the n-type semiconductor layer.

Abstract: Certain embodiments provide a semiconductor light emitting device including: a first metal layer; a stack film including a p-type nitride semiconductor layer, an active layer, and an n-type nitride semiconductor layer; an n-electrode; a second metal layer; and a protection film protecting an outer circumferential region of the upper face of the n-type nitride semiconductor layer, side faces of the stack film, a region of an upper face of the second metal layer other than a region in contact with the p-type nitride semiconductor layer, and a region of an upper face of the first metal layer other than a region in contact with the second metal layer. Concavities and convexities are formed in a region of the upper face of the n-type nitride semiconductor layer, the region being outside the region in which the n-electrode is provided and being outside the regions covered with the protection film.

Abstract: According to one embodiment, a nitride semiconductor device includes a stacked body and a functional layer. The stacked body includes an AlGaN layer of AlxGa1-xN (0<x?1), a first Si-containing layer, a first GaN layer, a second Si-containing layer, and a second GaN layer. The first Si-containing layer contacts an upper surface of the AlGaN layer. The first Si-containing layer contains Si at a concentration not less than 7×1019/cm3 and not more than 4×1020/cm3. The first GaN layer is provided on the first Si-containing layer. The first GaN layer includes a protrusion having an oblique surface tilted with respect to the upper surface. The second Si-containing layer is provided on the first GaN layer. The second Si-containing layer contains Si. The second GaN layer is provided on the second Si-containing layer. The functional layer is provided on the stacked body. The functional layer includes a nitride semiconductor.

Abstract: According to one embodiment, a semiconductor light emitting device includes: a stacked body, a wavelength conversion layer, a first metal layer, and a first insulating section. The stacked body includes: a first and a second semiconductor layers; and a first light emitting layer provided between the first and the second semiconductor layers. The wavelength conversion layer is configured to convert wavelength of light emitted from the first light emitting layer. The first semiconductor layer is placed between the first light emitting layer and the wavelength conversion layer. The first metal layer is electrically connected to the second semiconductor layer. The first insulating section is provided between a first side surface and a first side surface portion of the first metal layer and between the wavelength conversion layer and the first side surface portion.