Nitride-based semiconductor light emitting diode

• US 7,994,525 B2
• Filed: 12/14/2010
• Issued: 08/09/2011
• Est. Priority Date: 10/07/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung LED Co., Ltd. (Samsung Electronics Co. Ltd.)
• Inventors: Kim, Dong Joon, Lee, Hyuk Min, Kim, Hyun Kyung, Shin, Hyoun Soo
• Primary Examiner(s): Bryant; Kiesha R
• Assistant Examiner(s): Yang; Minchul
• Application Number:
  US12/967,558
• Publication Number:
  US 20110084305A1
• Time in Patent Office: 238 Days
• Field of Search: 257/13, 257/94, 257/103, 257/E33.025, 257/E33.03, 257/E33.034, 257/E33.062, 257/E33.063
• US Class Current: 257/94
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/32 containing nitrogen
• CPC Class Codes: H01L 33/38 with a particular shape

Abstract

A nitride-based semiconductor LED includes a substrate; an n-type nitride semiconductor layer formed on the substrate; an active layer and a p-type nitride semiconductor layer that are sequentially formed on a predetermined region of the n-type nitride semiconductor layer; a transparent electrode formed on the p-type nitride semiconductor layer; a p-electrode pad formed on the transparent electrode, the p-electrode pad being spaced from the outer edge line of the p-type nitride semiconductor layer by 50 to 200 μm; and an n-electrode pad formed on the n-type nitride semiconductor layer.

Claims

1. A nitride-based semiconductor LED comprising:

a substrate that is formed in a rectangle shape and of which a ratio of the width and the length is equal to or more than 1.5;

an n-type nitride semiconductor layer that is formed on the substrate and is composed of an n-type semiconductor material having a compositional formula of In_XAl_YGa_1-X--YN(0≦

X, 0≦

Y, and X+Y≦

1);

an active layer and a p-type nitride semiconductor layer that are sequentially formed on a predetermined region of the n-type nitride semiconductor layer, the active layer being composed of a semiconductor material having a compositional formula of In_XAl_yGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1)and the p-type nitride semiconductor layer being composed of a p-type semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1);

a transparent electrode that is formed on the p-type nitride semiconductor layer;

a p-electrode pad that is formed on the transparent electrode;

an n-electrode pad that is formed on the n-type nitride semiconductor layer; and

a buffer layer that is formed between the substrate and the n-type nitride semiconductor layer,

wherein the p-electrode pad, devoid of any elongated protrusion or any auxiliary electrode, is spaced at a distance of 50 to 200 μ

m an outer edge line of the p-type nitride semiconductor layer such that a uniform luminous effect is obtained in the entire LED, and wherein the center of the outer edge line of the p-type nitride semiconductor layer intersects with a straight line that connects a center of the p-electrode pad and a center of the n-electrode pad, and,

wherein the n-type semiconductor layer substantially surrounds the n-electrode.

2. The nitride-based semiconductor LED according to claim 1, wherein the n-type nitride semiconductor layer is a GaN layer or GaN/AlGaN layer doped with any one n-type conductive impurity selected from the group consisting of Si, Ge, and Sn,

the p-type nitride semiconductor layer is a GaN layer or GaN/AlGaN layer doped with any one p-type conductive impurity selected from the group consisting of Mg, Zn, and Be, and

the active layer is composed of an InGaN/GaN layer with a multi-quantum well structure.

3. The nitride-based semiconductor LED according to claim 1, wherein the p-electrode pad and the n-electrode pad are formed of Au or Au/Cr.

4. The nitride-based semiconductor LED according to claim 1, wherein

the distance between the p-electrode and the outer edge line of the p-type nitride semiconductor layer is longer that a distance between the n-electrode and another outer edge line of the p-type nitride semiconductor layer.

5. The nitride-based semiconductor LED of claim 1, wherein the buffer layer is composed of AlN/GaN.

6. A nitride-based semiconductor LED comprising:

a substrate that is formed in a rectangle shape and of which a ratio of the width and the length is equal to or more than 1.5;

an n-type nitride semiconductor layer that is formed on the substrate and is composed of an n-type semiconductor material having a compositional formula of In_XAl_YGa_1-X--YN(0≦

X, 0≦

Y, and X+Y≦

1);

an active layer and a p-type nitride semiconductor layer that are sequentially formed on a predetermined region of the n-type nitride semiconductor layer, the active layer being composed of a semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1) and the p-type nitride semiconductor layer being composed of a p-type semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1), the p-type nitride semiconductor layer having a p-electrode pad;

a transparent electrode that is formed on the p-type nitride semiconductor layer;

an n-electrode pad that is formed on the n-type nitride semiconductor layer; and

a buffer layer that is formed between the substrate and the n-type nitride semiconductor layer,

wherein the p-electrode pad, devoid of any elongated protrusion or any auxiliary electrode, is spaced at a distance of 50 to 200 μ

m an outer edge line of the p-type nitride semiconductor layer such that a uniform luminous effect is obtained in the entire LED, and wherein the center of the outer edge line of the p-type nitride semiconductor layer intersects with a straight line that connects a center of the p-electrode pad and a center of the n-electrode pad, and

wherein the n-type semiconductor layer substantially surrounds the n-electrode.

7. The nitride-based semiconductor LED according to claim 6, wherein

the distance between the p-electrode and the outer edge line of the p-type nitride semiconductor layer is longer that a distance between the n-electrode and another outer edge line of the p-type nitride semiconductor layer.

8. The nitride-based semiconductor LED of claim 6, wherein the buffer layer is composed of AlN/GaN.

9. A nitride-based semiconductor LED comprising:

a substrate that is formed in a rectangle shape and of which a ratio of the width and the length is equal to or more than 1.5;

an n-type nitride semiconductor layer that is formed on the substrate and is composed of an n-type semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1);

an active layer and a p-type nitride semiconductor layer that are sequentially formed on a predetermined region of the n-type nitride semiconductor layer, the active layer being composed of a semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1)and the p-type nitride semiconductor layer being composed of a p-type semiconductor material having a compositional formula of In_XAl_YGa_1-X-YN(0≦

X, 0≦

Y, and X+Y≦

1);

a transparent electrode that is formed on the p-type nitride semiconductor layer;

a p-electrode pad that is formed on the transparent electrode, a center of an outer edge line of a p-type nitride semiconductor layer being intersected by a straight line that connects a center of the p-electrode pad and a center of the n-electrode pad, wherein the p-electrode pad is spaced at a distance of 50 to 200 μ

m from the outer edge line of the p-type nitride semiconductor layer such that a uniform luminous effect is obtained in the entire LED;

an n-electrode pad that is formed on the n-type nitride semiconductor layer; and

a buffer layer that is formed between the substrate and the n-type nitride semiconductor layer,

wherein the n-type semiconductor layer substantially surrounds the n-electrode.

10. The nitride-based semiconductor LED of claim 9, wherein the buffer layer is composed of AlN/GaN.