III-nitride light emitting device with p-type active layer

Details III-nitride light emitting device with p-type active layer III-nitride light emitting device with p-type active layer

2002-07-30

2004-12-28

Pham, Long (Department: 2814)

Active solid-state devices (e.g., transistors, solid-state diode

Incoherent light emitter structure

C257S098000

Reexamination Certificate

active

06835957

ABSTRACT:

BACKGROUND
1. Field of Invention
This invention relates to III-nitride light emitting devices with at least one p-type layer in the active region.
2. Description of Related Art
Semiconductor light-emitting devices (LEDs) are among the most efficient light sources currently available. Materials systems currently of interest in the manufacture of high-brightness LEDs capable of operation across the visible spectrum include Group III-V semiconductors, particularly binary, ternary, and quaternary alloys of gallium, aluminum, indium, and nitrogen with the general formula Al
x
In
y
Ga
z
N, 0≦x≦1, 0≦y≦1, 0≦z≦1, x+y+z=1, also referred to as III-nitride materials. Typically, III-nitride light emitting devices are fabricated by epitaxially growing a stack of semiconductor layers of different compositions and dopant concentrations on a sapphire, silicon carbide, or III-nitride substrate by metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), or other epitaxial techniques. The stack often includes one or more n-type layers doped with, for example, Si, formed over the substrate, a light emitting or active region formed over the n-type layer or layers, and one or more p-type layers doped with, for example, Mg, formed over the active region. The active region is n-type (typically Si-doped or undoped).
SUMMARY
In accordance with embodiments of the invention, a III-nitride light emitting device includes an n-type layer, a p-type layer, and an active region capable of emitting light between the p-type layer and the n-type layer. The active region includes at least one additional p-type layer. The p-type layer in the active region may be a quantum well layer or a barrier layer. In some embodiments, both the quantum well layers and the barrier layers in the active region are p-type.
In some embodiments, the p-type layer in the active region has an average dislocation density less than about 5×10
8
cm
−2
. Several methods are disclosed for fabricating p-type layers in the active region with low defect densities. First, the device layers may be fabricated on a AlInGaN substrate with low defect density. Second the device layers may be fabricated on a thick AlInGaN layer formed by hydride vapor phase epitaxy. Third, the device layers may be fabricated on an AlInGaN layer formed by epitaxial lateral overgrowth.


REFERENCES:
patent: 5656832 (1997-08-01), Ohba et al.
patent: 5684309 (1997-11-01), McIntosh et al.
patent: 5747832 (1998-05-01), Nakamura et al.
patent: 5874747 (1999-02-01), Redwing et al.
patent: 6153894 (2000-11-01), Udagawa
patent: 6440823 (2002-08-01), Vaudo et al.
Takashi Mukai et al., “InGaN-Based Blue Light-Emitting Diodes Grown on Epitaxially Laterally Overgrown GaN Substrates”, Japanese Journal of Applied Physics, 1998, pp. L839-L841.

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