Crystal Is, Inc.

Asahi Kasei Kabushiki Kaisha

Tomohiro Morishita

Leo J Schowalter

Shawn R Gibb

James R Grandusky

Shawn Robert Gibb

Kosuke Sato

Craig Moe

Akira Yoshikawa

Ziyi Zhang

Aya Yokoyama

Yoshihito Hagihara

Ryosuke Hasegawa

Motoaki Iwaya

To provide a nitride semiconductor element having a better contact resistance reduction effect also in the case of a light emitting element containing AlGaN having a high Al composition. The nitride semiconductor element has a substrate, a first conductivity type first nitride semiconductor layerformed on the substrate, and a first electrode layerformed on the first nitride semiconductor layer. The first electrode layercontains aluminum and nickel, and both aluminum and an alloy containing aluminum and nickel are present in a contact surface to the first nitride semiconductor layeror in the vicinity of the contact surface.

Nitride semiconductor element, nitride semiconductor light emitting element, ultraviolet light emitting element

A nitride semiconductor substrate includes a sapphire substrate and a nitride semiconductor layer formed thereon and containing a group III element including Al and nitrogen as a main component. A surface of the sapphire substrate where the nitride semiconductor layer is formed includes recesses having a maximum opening size of from 2 nm to 60 nm in an amount of from 1&#xd7;10pieces to 1&#xd7;10pieces per cm. The recesses and surfaces immediately above the recesses form spaces. Of a surface of the nitride semiconductor layer on the sapphire substrate side, a height difference &#x394;H between a surface immediately above of each recess and a surface in contact with a flat surface is 10 nm or less. A portion of the nitride semiconductor layer above each recess has a crystalline structure produced by growth along a polar plane of the group III element.

Nitride semiconductor substrate and method for manufacturing same

In various embodiments, light-emitting devices incorporate graded layers with compositional offsets at one or both end points of the graded layer to promote formation of two-dimensional carrier gases and polarization doping, thereby enhancing device performance.

Ultraviolet light-emitting devices incorporating graded layers and compositional offsets

Ultraviolet light-emitting devices incorporating two-dimensional hole gases

Growing community of inventors

Tokyo, Japan

Tomohiro Morishita