Gallium nitride based light-emitting device

A light-emitting structure for a light emitting diode (LED), comprising a resonant cavity structure, a contact layer, an n-type metal electrode and a p-type metal electrode, wherein:

• said-resonant cavity structure formed by a metal reflector, a substrate, a buffer layer an n-GaN based layer, an MQW active layer and a p-type distributed Bragg reflector (DBR), wherein and said substrate comprises sapphire;
• said contact layer being a p-GaN based layer and formed over said p-type DBR;
• said n-type metal electrode disposed over an exposing layer of said n-GaN layer;
• and
• said p-type metal electrode disposed over said p-GaN layer;
• wherein said MQW active layer comprises a material so that said MQW active layer generates a light with a wavelength comprising 380-600 nm in response to an applied electric power between said n-type metal electrode and said p-type metal electrode.

A light-emitting structure for a light-emitting device (LED) comprising:

• a metal reflector on a bottom side of a substrate, wherein said metal reflector has a thickness of 50 Å to 10 μm and is made of a conductive metal or metal alloy;
• an LT-GaN/HT-GaN buffer layer having a first formed LT-GaN buffer layer on said substrate and a then formed HT-GaN buffer layer on said LT-GaN buffer layer, wherein said LT-GaN buffer layer has a thickness of 30 to 500 Å while said HT-GaN buffer layer with a thickness of 0.5 to 6 μm;
• an n-GaN semiconductor layer having a thickness of 2 to 6 μm;
• an InGaN/GaN MQW active layer;
• a p-AlGaN/GaN distributed Bragg reflector (DBR);
• and
• a p+-GaN based semiconductor layer having a thickness of 0.2 to 0.5 μm;
• wherein said substrate comprising sapphire and said MQW active layer emits a light with a wavelength comprising 380-600 nm in response to an applied electric power;

A method for manufacturing a light-emitting structure of a light-emitting device (LED), comprising:

• (a) forming a buffer layer over an upper side of a substrate wherein said substrate comprises sapphire, silicon carbide (SiC), silicon (Si) and gallium nitride (GaN);
• (b) forming an n-type DBR on said buffer layer;
• (c) forming an n-GaN based layer over said n-type DBR;
• (d) forming an MQW active layer over said n-GaN based layer, wherein said MQW active layer comprises a material so that said MQW active layer emits a light with a wavelength of 380-600 nm upon an applied electric power;
• (e) forming a p-type distributed Brag reflector DBR) over said MQW active layer;
• and
• (f) forming a p-GaN based layer over said p-type DBR and etching away a portion of said p-GaN based layer, said p-type DBR, said MQW active layer and said n-GaN based layer whereby said n-GaN based layer has an exposing region and disposing said n-type electrode over said exposing region of said n-GaN based layer and disposing said p-type electrode over said p-GaN based layer.

A light-emitting structure for a light emitting diode (LED), comprising a substrate, a resonant cavity structure, a contact layer, an n-type metal electrode and a p-type metal electrode, wherein:

• said substrate comprising sapphire and having a buffer layer thereon;
• said resonant cavity structure formed over said buffer layer, comprising an n-type distributed Bragg reflector (DBR), an n-GaN based layer, a multi-quantum well (MQW) active layer and a p-type DBR layers;
• said contact layer being a p-GaN based layer and formed over said p-type DBR;
• said n-type metal electrode disposed over an exposing region of said n-GaN layer;
• and
• said p-type metal electrode disposed over said p-GaN based layer;
• wherein said MQW active layer comprises a material so that said MQW active layer generates a light with a wavelength of 380 nm to 600 nm in response to an applied electric power between said p-type electrode and said n-type electrode.

A light-emitting structure for a light-emitting device (LED) comprised of an epitaxial structure, comprising:

• an LT-GaN/HT-GaN buffer layer having a first formed LT-GaN buffer layer on a substrate and a then formed HT-GaN buffer layer on said LT-GaN buffer layer, wherein said LT-GaN buffer layer has a thickness of 30 to 500 Å while said HT-GaN buffer layer has a thickness of 0.5 to 6μm;
• an n-AlGaN/GaN distributed Bragg reflector (DBR);
• an n-GaN semiconductor layer having a thickness of 2 to 6 μm;
• an InGaN/GaN MQW active layer;
• a p-AlGaN/GaN DBR;
• and
• a p+-GaN based semiconductor layer having a thickness of 0.2 to 0.5 μm;
• wherein said substrate comprises sapphire and said MQW active layer emits a light with a wavelength comprising 380-600 nm in response to an applied electric power.