Nitride semiconductor light-emitting device and method for producing the same

• US 9,530,932 B2
• Filed: 05/26/2015
• Issued: 12/27/2016
• Est. Priority Date: 06/30/2011
• Status: Active Grant

• Current Assignee: Sharp Fukuyama Laser Co., Ltd. (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Fudeta, Mayuko, Komada, Satoshi, Kaihara, Ryu
• Primary Examiner(s): Vu, David
• Assistant Examiner(s): INOUSSA, MOULOUCOULAY
• Application Number:
  US14/721,760
• Publication Number:
  US 20150255673A1
• Time in Patent Office: 581 Days
• Field of Search: 257/94, 257/98, 257/102, 257/103, 257/618, 438/689
• US Class Current: 1/1
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 33/04 with a quantum effect structure or superlattice, e.g. tunnel junction
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H01L 33/32 containing nitrogen

Abstract

A nitride semiconductor light-emitting device has a first conductive-type nitride semiconductor layer, a superlattice layer provided on the first conductive-type nitride semiconductor layer, an active layer provided on the superlattice layer, and a second conductive-type nitride semiconductor layer provided on the active layer. An average carrier concentration of the superlattice layer is higher than an average carrier concentration of the active layer.

Claims

1. A nitride semiconductor light-emitting device comprising:

a sapphire substrate having a convexoconcave-worked upper face;

a base layer made of Al_s1Ga_t1In_u1N (0≦

s1≦

1, 0≦

t1≦

1, 0≦

u1≦

1, s1+t1+u1≠

0) provided on a growth face of the sapphire substrate;

a contact layer made of a nitride semiconductor of an n-type, provided on said base layer;

a superlattice layer provided on said contact layer and including impurities of the n-type;

an active layer provided on said superlattice layer and including impurities of the n-type; and

a nitride semiconductor layer of a p-type, provided on said active layer, wherein

an average carrier concentration of said superlattice layer is higher than an average carrier concentration of said active layer,

wherein the superlattice layer consists essentially of nitride semiconductors, and

the sapphire substrate, the base layer, the contact layer, the superlattice layer, the active layer, and the nitride semiconductor layer are arranged in this order.

2. The nitride semiconductor light-emitting device according to claim 1, wherein the average carrier concentration of said superlattice layer is greater than or equal to 1.2 times the average carrier concentration of said active layer.

3. The nitride semiconductor light-emitting device according to claim 1, wherein said superlattice layer has two or more layers of a doped layer.

4. The nitride semiconductor light-emitting device according to claim 1, wherein

said active layer has a well layer and a barrier layer, and

said barrier layer is an undoped layer not containing a conductive-type impurity, or a concentration of the conductive-type impurity in said barrier layer is less than or equal to 8×

10¹⁷ cm<sup>−

3</sup>.

5. The nitride semiconductor light-emitting device according to claim 1, wherein

said active layer has a well layer and a barrier layer, and

a concentration of the impurities of the n-type in said barrier layer is higher than a concentration of the impurities of the n-type in said well layer.