NITRIDE SEMICONDUCTOR LIGHT-EMITTING DEVICE WITH ELECTRODE PATTERN
A nitride semiconductor light-emitting device with an electron pattern that applies current uniformly to an active layer to improve light emission efficiency is provided. The nitride semiconductor light-emitting device includes multiple layers of a substrate, an n-type nitride layer, an active layer of a multi-quantum-well structure, and a p-type nitride layer. The nitride semiconductor light-emitting device further includes a p-electrode pattern and an n-electrode pattern. The p-electrode pattern includes one or more p-pads disposed on the p-type nitride layer, and one or more p-fingers extending from the p-pads. The n-electrode pattern includes one or more n-pads disposed on an exposed region of the n-type nitride layer to correspond to the p-pads, and one or more n-fingers extending from the n-pads. The n-fingers have identical resistance, and the p-fingers have identical resistance to improve current spreading to the active layer.
1 . A nitride semiconductor light-emitting device including multiple layers of a substrate, an n-type nitride layer, an active layer of a multi-quantum-well structure, and a p-type nitride layer, the nitride semiconductor light-emitting device comprising:
a p-electrode pattern comprising one or more p-pads disposed on the p-type nitride layer, and one or more p-fingers extending from the p-pads; and
an n-electrode pattern comprising one or more n-pads disposed on an exposed region of the n-type nitride layer to correspond to the p-pads, and one or more n-fingers extending from the n-pads,
wherein the n-fingers have identical resistance, and the p-fingers have identical resistance to improve current spreading to the active layer.
2 . The nitride semiconductor light-emitting device of claim 1 , wherein each of the p-fingers satisfies a relation, R=ρ L/A, where R, ρ, L and A are a resistance, a resistivity, a length, and a cross-sectional area of the p-finger, respectively, so that the cross-sectional area is proportional to the length L.
3 . The nitride semiconductor light-emitting device of claim 2 , wherein the p-fingers comprise:
a first p-finger having a first length and a first cross-sectional area; and
a second p-finger having a second length greater than the first length,
wherein a second cross-sectional area of the second p-finger satisfies a relation,
L
1
A
1
=
L
2
A
2
,
where L 1 , L 2 , A 1 and A 2 are the first length, the second length, the first cross-sectional area and the second cross-sectional area, respectively.
4 . The nitride semiconductor light-emitting device of claim 1 , wherein each of the n-fingers satisfies a relation, R=ρ L/A, where R, ρ, L and A are a resistance, a resistivity, a length, and a cross-sectional area of the n-finger, respectively, so that the cross-sectional area is proportional to the length L.
5 . The nitride semiconductor light-emitting device of claim 4 , wherein the n-fingers comprise:
a first n-finger having a first length and a first cross-sectional area;
a second n-finger having a second length greater than the first length; and
a third n-finger having a third length greater than the second length,
wherein a second cross-sectional area of the second p-finger and a third cross-sectional area of the third p-finger satisfy a relation,
L
11
A
11
=
L
12
A
12
=
L
13
A
13
,
where L 11 , L 12 , L 13 , A 11 , A 12 and A 13 are the first length, the second length, the third length, the first cross-sectional area, the second cross-sectional area and the third cross-sectional area, respectively.
6 . The nitride semiconductor light-emitting device of claim 1 , wherein the nitride semiconductor light-emitting device has a horizontal type structure, and
the n-fingers and the p-fingers are disposed alternatingly and have at least one bent section, respectively.
7 . A nitride semiconductor light-emitting device comprising:
an active layer having a multi-quantum-well structure between an n-type nitride layer and a p-type nitride layer;
a p-electrode pattern comprising one or more p-pads disposed on the p-type nitride layer, and one or more p-fingers extending from the p-pads; and
an n-electrode pattern comprising one or more n-pads disposed on an exposed region of the n-type nitride layer, and one or more n-fingers extending from the n-pads,
wherein the n-fingers have identical resistance, and the p-fingers have identical resistance to improve current spreading to the active layer.
8 . The nitride semiconductor light-emitting device of claim 7 , wherein each of the p-fingers satisfies a relation, R=ρ L/A, where R, ρ, L and A are a resistance, a resistivity, a length, and a cross-sectional area of the p-finger, respectively, so that the cross-sectional area is proportional to the length L.
9 . The nitride semiconductor light-emitting device of claim 7 , wherein each of the n-fingers satisfies a relation, R=ρ L/A, where R, ρ, L and A are a resistance, a resistivity, a length, and a cross-sectional area of the n-finger, respectively, so that the cross-sectional area is proportional to the length L.
10 . The nitride semiconductor light-emitting device of claim 8 , wherein the p-fingers or the n-fingers comprise a plurality of fingers extending alternately and radially.
11 . The nitride semiconductor light-emitting device of claim 8 , wherein the n-fingers or the p-fingers each has at least one bent section.