Abstract: In general, according to one embodiment, a semiconductor light emitting element includes: a first semiconductor layer; a second semiconductor layer; a light emitting layer. The light emitting layer includes a well layer with a thickness of t1 (nanometers). The well layer includes InxGa1-xN having an In composition ratio x higher than 0 and lower than 1. The first semiconductor layer has a tensile strain of not less than 0.02 percent and not more than 0.25 percent in a plane perpendicular to a stacking direction. A peak wavelength ?p (nanometers) of light satisfies a relationship of ?p=a1+a2×(x+(t1?3.0)×a3). The a1 is not less than 359 and not more than 363. The a2 is not less than 534 and not more than 550. The a3 is not less than 0.0205 and not more than 0.0235.

Abstract: According to one embodiment, a semiconductor light emitting device includes first and second semiconductor layers, and a light emitting unit. The light emitting unit is provided between the first and second semiconductor layers and includes well layers and barrier layers. The barrier layers include p-side and n-side barrier layers, and a first intermediate barrier layer. The n-side barrier layer is provided between the p-side barrier layer and the first semiconductor layer. The first intermediate barrier layer is provided between the barrier layers. The well layers include p-side and n-side well layers, and a first intermediate well layer. The p-side well layer is provided between the p-side barrier layer and the second semiconductor layer. The n-side well layer is provided between the n-side barrier layer and the first intermediate barrier layer. The first intermediate well layer is provided between the first intermediate barrier layer and the p-side barrier layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes n-type and p-type semiconductor layers containing a nitride semiconductor and a light emitting layer. The emitting layer includes a barrier layer containing III group elements, and a well layer stacked with the barrier layer and containing III group elements. The barrier layer is divided into a first portion on an n-type semiconductor layer side and a second portion on a p-type semiconductor layer side, an In composition ratio in the III group elements of the second portion is lower than that of the first portion. The well layer is divided into a third portion on an n-type semiconductor layer side and a fourth portion on a p-type semiconductor layer side, an In composition ratio in the III group elements of the fourth portion is higher than that of the third portion.

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 portion. The light emitting portion is provided between the semiconductor layers and includes barrier layers and well layers alternately stacked. An n-side end well layer which is closest to the n-type semiconductor layer contains InwnGa1-wnN and has a layer thickness twn. An n-side end barrier layer which is closest to the n-type semiconductor layer contains InbnGa1-bnN and has a layer thickness tbn. A p-side end well layer which is closest to the p-type semiconductor layer contains InwpGa1-wpN and has a layer thickness twp. A p-side end barrier layer which is closest to the p-type semiconductor contains InbpGa1-bpN and has a layer thickness tbp. A value of (wp×twp+bp×tbp)/(twp+tbp) is higher than (wn×twn+bn×tbn)/(twn+tbn) and is not higher than 5 times (wn×twn+bn×tbn)/(twn+tbn).

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 element includes a first semiconductor layer of an n-type, a second semiconductor layer of a p-type, and a light emitting unit. The first semiconductor layer includes a nitride semiconductor. The second semiconductor layer includes a nitride semiconductor. The light emitting unit is provided between the first semiconductor layer and the second semiconductor layer. The light emitting unit includes a plurality of well layers stacked alternately with a plurality of barrier layers. The well layers include a first p-side well layer most proximal to the second semiconductor layer, and a second p-side well layer second most proximal to the second semiconductor layer. A localization energy of excitons of the first p-side well layer is smaller than a localization energy of excitons of the second p-side well layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type layer, a light emitting layer, a p-type layer, and a transparent electrode. The n-type layer includes a nitride semiconductor and has a thickness not more than 500 nm. The light emitting layer is provided on the n-type layer. The p-type layer is provided on the light emitting layer and includes a nitride semiconductor. The transparent electrode contacts the n-type layer. The n-type layer is disposed between the transparent electrode and the light emitting layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes first and second semiconductor layers, and a light emitting unit. The light emitting unit is provided between the first and second semiconductor layers and includes well layers and barrier layers. The barrier layers include p-side and n-side barrier layers, and a first intermediate barrier layer. The n-side barrier layer is provided between the p-side barrier layer and the first semiconductor layer. The first intermediate barrier layer is provided between the barrier layers. The well layers include p-side and n-side well layers, and a first intermediate well layer. The p-side well layer is provided between the p-side barrier layer and the second semiconductor layer. The n-side well layer is provided between the n-side barrier layer and the first intermediate barrier layer. The first intermediate well layer is provided between the first intermediate barrier layer and the p-side barrier layer.

Abstract: According to one embodiment, the luminescent material shows a luminescence peak in a wavelength range of 570 to 670 nm when excited with light having an emission peak in a wavelength range of 250 to 520 nm. The luminescent material includes a host material having a crystal structure substantially same as the crystal structure of Sr2Si7Al3ON13. The host material is activated by Eu, and includes Sr and Ca to satisfy a relationship of 0.008?MCa/(MSr+MCa)?0.114, where MCa is a number of moles of Ca and MSr is a number of moles of Sr.

Abstract: According to one embodiment, a semiconductor light-emitting device includes an n-type semiconductor layer including a nitride semiconductor, a p-type semiconductor layer including a nitride semiconductor, a light-emitting portion and a stacked body. The light-emitting portion is provided between the n-type and p-type semiconductor layers and includes a barrier layer and a well layer. The well layer is stacked with the barrier layer. The stacked body is provided between the light-emitting portion and the n-type semiconductor layer and includes a first layer and a second layer. The second layer is stacked with the first layer. Average In composition ratio of the stacked body is higher than 0.4 times average In composition ratio of the light-emitting portion. The layer thickness tb of the barrier layer is 10 nanometers or less.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type layer, a light emitting layer, a p-type layer, and a transparent electrode. The n-type layer includes a nitride semiconductor and has a thickness not more than 500 nm. The light emitting layer is provided on the n-type layer. The p-type layer is provided on the light emitting layer and includes a nitride semiconductor. The transparent electrode contacts the n-type layer. The n-type layer is disposed between the transparent electrode and the light emitting layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes a first semiconductor layer, a second semiconductor layer, a light emitting part, and a multilayered structural body. The light emitting part is provided between the first and second semiconductor layers and includes barrier layers and well layers alternately stacked. The multilayered structural body is provided between the first semiconductor layer and the light emitting part and includes high energy layers and low energy layers alternately stacked. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the multilayered structural body. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the light emitting part.

Abstract: A semiconductor light emitting element includes a first substrate, a stacked body, an electrode, and a conductive layer. The first substrate has a first face and a first side face. The first side face intersects the first face. The first substrate includes a plurality of conductive portions and a plurality of insulating portions arranged alternately. The stacked body is aligned with the first substrate. The stacked body includes first and second semiconductor layers and a light emitting layer. The electrode is electrically connected to the first semiconductor layer. The conductive layer is electrically connected to at least one of the conductive portions and the second semiconductor layer. At least one of the insulating portions is disposed between the first side face and a portion of the conductive layer nearest to the first side face.

Abstract: In general, according to one embodiment, a semiconductor light emitting element includes: a first semiconductor layer; a second semiconductor layer; a light emitting layer. The light emitting layer includes a well layer with a thickness of t1 (nanometers). The well layer includes InxGa1-xN having an In composition ratio x higher than 0 and lower than 1. The first semiconductor layer has a tensile strain of not less than 0.02 percent and not more than 0.25 percent in a plane perpendicular to a stacking direction. A peak wavelength ?p (nanometers) of light satisfies a relationship of ?p=a1+a2×(x+(t1?3.0)×a3). The a1 is not less than 359 and not more than 363. The a2 is not less than 534 and not more than 550. The a3 is not less than 0.0205 and not more than 0.0235.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type semiconductor layer, a p-type semiconductor layer, a light emitting portion, a first layer, a second layer, and an intermediate layer. The semiconductor layers include nitride semiconductor. The light emitting portion is provided between the n-type semiconductor layer and the p-type semiconductor layer and includes a quantum well layer. The first layer is provided between the light emitting portion and the p-type semiconductor layer and includes AlX1Ga1-x1N having first Al composition ratio x1. The second layer is provided between the first layer and the p-type semiconductor layer and includes Alx2Ga1-x2N having second Al composition ratio x2 higher than the first Al composition ratio x1. The intermediate layer is provided between the first layer and the light emitting portion and has a thickness not smaller than 3 nanometers and not larger than 8 nanometers and includes Inz1Ga1-z1N (0?z1<1).

Abstract: According to one embodiment, a semiconductor light emitting device includes a first semiconductor layer, a second semiconductor layer, a light emitting part, and a multilayered structural body. The light emitting part is provided between the first and second semiconductor layers and includes barrier layers and well layers alternately stacked. The multilayered structural body is provided between the first semiconductor layer and the light emitting part and includes high energy layers and low energy layers alternately stacked. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the multilayered structural body. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the light emitting part.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type first semiconductor layer, a p-type second semiconductor layer and a light emitting layer. The light emitting layer is provided between the first and second semiconductor layers, and includes a plurality of barrier layers including a nitride semiconductor and a well layer provided between the barrier layers and including a nitride semiconductor containing In. The barrier layers and the well layer are stacked in a first direction from the second semiconductor layer toward the first semiconductor layer. The well layer has a p-side interface part and an n-side interface part. Each of the p-side and the n-side interface part include an interface with one of the barrier layers. A variation in a concentration of In in a surface perpendicular to the first direction of the p-side interface part is not more than that of the n-side interface part.

Abstract: According to one embodiment, a semiconductor light emitting device includes an n-type layer, a light emitting layer, a p-type layer, and a transparent electrode. The n-type layer includes a nitride semiconductor and has a thickness not more than 500 nm. The light emitting layer is provided on the n-type layer. The p-type layer is provided on the light emitting layer and includes a nitride semiconductor. The transparent electrode contacts the n-type layer. The n-type layer is disposed between the transparent electrode and the light emitting layer.

Abstract: According to one embodiment, a semiconductor light emitting device includes a first semiconductor layer, a second semiconductor layer, a light emitting part, and a multilayered structural body. The light emitting part is provided between the first and second semiconductor layers and includes barrier layers and well layers alternately stacked. The multilayered structural body is provided between the first semiconductor layer and the light emitting part and includes high energy layers and low energy layers alternately stacked. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the multilayered structural body. An average In composition ratio on a side of the second semiconductor is higher than that on a side of the first semiconductor in the light emitting part.

Abstract: According to one embodiment, a semiconductor light emitting element includes a light reflecting layer, first second, third and fourth semiconductor layers, first and second light emitting layers, and a first light transmitting layer. The second semiconductor layer is provided between the first semiconductor layer and the light reflecting layer. The first light emitting layer is provided between the first and second semiconductor layers. The first light transmitting layer is provided between the second semiconductor layer and the light reflecting layer. The third semiconductor layer is provided between the first light transmitting layer and the light reflecting layer. The fourth semiconductor layer is provided between the third semiconductor layer and the light reflecting layer. The second light emitting layer is provided between the third and fourth semiconductor layers. The light reflecting layer is electrically connected to one selected from the third and fourth semiconductor layers.