Light-emitting device of gallium nitride compound semiconductor

US5408120A · kind A · utility

Assignees

• TOYODA GOSEI CO., LTD. · JP
• KABUSHIKI KAISHA TOYOTA CHUO KENKYUSHO · JP

Inventors

• Katsuhide Manabe · Ichinomiya, JP
• Masahiro Kotaki · Inazawa, JP
• Makoto Tamaki · Komaki, JP
• Masafumi Hashimoto · Tokyo, JP

Key dates

• Filing date: Jan 22, 1993
• Grant date: Apr 18, 1995
• Expiry date: Jan 22, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10H20/8312

Abstract

A light-emitting diode of GaN compound semiconductor emits a blue light from a plane rather than dots for improved luminous intensity. This diode includes a first electrode associated with a high-carrier density n.sup.+ layer and a second electrode associated with a high-impurity density i.sub.H -layer. These electrodes are made up of a first Ni layer (110 .ANG. thick), a second Ni layer (1000 .ANG. thick), an Al layer (1500 .ANG. thick), a Ti layer (1000 .ANG. thick), and a third Ni layer (2500 .ANG. thick). The Ni layers of dual structure permit a buffer layer to be formed between them. This buffer layer prevents the Ni layer from peeling. The direct contact of the Ni layer with GaN lowers a drive voltage for light emission and increases luminous intensity.