TWI504021B - Semiconductor light emitting device - Google Patents

Description

Semiconductor light emitting device

The present invention relates to a semiconductor light emitting device, and more particularly to a semiconductor light emitting device, the electrode of which includes an extension.

Due to its low power consumption, small size and long service life, the LED components are widely used in household appliances such as indicator lights, backlights for liquid crystal displays, graphic display screens, and automotive third-lamp lamps. In recent years, light-emitting diode materials such as aluminum gallium indium phosphide (AlGaInP) and aluminum gallium indium nitride (AlGaInN) have been successfully developed, so that conventional incandescent light bulbs can be replaced with light-emitting diode elements in many applications.

1 and 2 are a plan view and a cross-sectional view, respectively, of a conventional light-emitting diode 10, wherein Fig. 2 is a cross-sectional view taken along line 2-2' of Fig. 1. The N-type semiconductor layer 11, the light-emitting layer 16, and the P-type semiconductor layer 12 are sequentially formed on the substrate 17, and then the N-type electrode 14 and the P-type electrode 15 are produced by etching and deposition. The above-mentioned luminescent layer 16 may be a homo junction, a hetero-junction, a double hetero-structure, a single quantum well, or a multiple quantum well (multiple). Quantum well) and so on.

Generally, the electron system moves from below the N-type electrode 14 to the P-type electrode 15, and the hole also moves from the P-type electrode 15 to the N-type electrode 14 in the opposite direction. When electrons and holes are combined in the light-emitting layer 16, energy is released to emit light. Moreover, the electron and the hole have the lowest path of resistance between the P-type electrode 15 and the N-type electrode 14 as the main moving path. Therefore, the combination of electrons and holes is often concentrated on the partial area P of the light-emitting layer 16, which not only causes most of the light-emitting layer 16 to be unable to effectively emit light, but also causes the generated heat to concentrate, and reduces luminous efficiency and reliability. Such a conventional P-type and N-type electrode configuration is obviously only suitable for a small-sized (for example, 14 mil × 14 mil) light-emitting diode 10, and is not suitable for a large-area rectangular light-emitting diode.

In order to solve the above problems, the present invention discloses a semiconductor light emitting device comprising: a substrate; a first type semiconductor layer formed on the substrate; a light emitting layer and a second type semiconductor layer are sequentially formed in the portion a first type semiconductor layer is exposed on the first semiconductor layer; a first type electrode is formed on the bare first type semiconductor layer, and includes a first body portion, a first extension portion, and a first a second extending portion, the first extending portion includes a first extending portion extending from the first body portion in a first direction and a second extending portion connecting the first extending portion and extending in a second direction, and the second extending portion The second extending portion includes a third extending portion extending from the first body portion in a third direction, and a fourth extending portion connecting the third extending portion and extending in a second direction, wherein the second The fourth extending sections are parallel to each other, the first direction and the third direction and the second direction are perpendicular to each other, and the first and third directions are 180 degrees opposite to each other; and a second type electrode, Formed on The second type semiconductor layer includes a second body portion and a third extension portion, wherein the third extension portion is located between the second and fourth extension portions and is from the second body portion Extending in the fourth direction, the fourth direction and the second direction are opposite to each other by 180 degrees, a first projection of the third extension on a plane and a second and a third projection of the second extension section and the fourth extension section on the plane along the first and the The three-way observations only partially overlap.

Since the first type electrode includes the first extension portion, the second type electrode includes the second extension portion, so that the moving path of the electron and the hole can be increased, and even if the diffusion of the electron and the hole is more uniform, Avoid the concentration of heat generated to reduce luminous efficiency and reliability. Furthermore, since the first projection of the first extension portion and the second projection of the second extension portion only partially overlap, the first extension portion can be used to diffuse the current of the second extension portion to one side, Avoid the concentration of current, which will improve the electrostatic protection and reduce component failure. In addition, since the first projection of the first extension portion and the second projection of the second extension portion only partially overlap, the uncovered area of the first extension portion and the second extension portion can still serve as a light-emitting area.

The present invention further discloses a semiconductor light emitting device comprising a substrate; a first type semiconductor layer formed on the substrate; a light emitting layer and a second type semiconductor layer are sequentially formed on a portion of the first type semiconductor layer, and a first portion of the first semiconductor layer is formed on the exposed first type semiconductor layer, and includes a first body portion and a first extension portion, wherein the first extension portion is from the The first body portion extends in a first direction; and a second type electrode is formed on the second type semiconductor layer, and includes a second body portion and a second extension portion, the second extension portion is from the first The second body portion extends in a second direction, and the first direction and the second direction are opposite to each other by 180 degrees, wherein the first extension portion is in a first plane on a plane The projection and the second projection of the second extension on the plane only partially overlap in a direction perpendicular to the first direction and the third direction of the second direction.

Since the first type electrode includes the first extension portion, the second type electrode includes the second extension portion, so that the moving path of the electron and the hole can be increased, and even if the diffusion of the electron and the hole is more uniform, Avoid the concentration of heat generated to reduce luminous efficiency and reliability. Furthermore, since the first projection of the first extension portion and the second projection of the second extension portion only partially overlap, the first extension portion can be used to diffuse the current of the second extension portion to one side, Avoid the concentration of current, which will improve the electrostatic protection and reduce component failure. In addition, since the first projection of the first extension portion and the second projection of the second extension portion only partially overlap, the uncovered area of the first extension portion and the second extension portion can still serve as a light-emitting area.

The above and other objects, features, and advantages of the present invention will become more apparent from the accompanying drawings.

[Example 1]

Referring to Figures 3a, 3b and 4, a semiconductor light emitting device 100 in accordance with a first embodiment of the present invention is shown. The semiconductor light emitting device 100 can be a rectangular light emitting diode. The semiconductor light-emitting device 100 includes a substrate 110, a first-type semiconductor layer 120, a light-emitting layer 130, a second-type semiconductor layer 140, a first-type electrode 150, and a second-type electrode 170. The first type semiconductor layer 120 is formed on the substrate 110. The luminescent layer 130 and a second half The conductor layer 140 is sequentially formed on a portion of the first type semiconductor layer 120, and a portion of the first type semiconductor layer 120 is exposed. The luminescent layer 130 can be a homo junction, a hetero-junction, a double hetero-structure, a single quantum well, or a multiple quantum well. Well) and so on.

The first type of electrode 150 is formed on the exposed first type semiconductor layer 120, and includes a first body portion 1510, a first extending portion 1511 and a second extending portion 1512. The first extending portion 1511 includes a first extending portion 1511. The first extension portion 1511a extends from the first body portion 1510 in the first direction 1 and a second extension portion 1511b connects the first extension portion 1511a and extends in the second direction 2, and the second extension portion 1512 A third extension section 1512a extends from the first body portion 1510 toward the third direction 3, and a fourth extension section 1512b connects the third extension section 1512a and extends in the second direction 2. The second and fourth extending sections 1511b, 1512b are parallel to each other, the first direction 1 and the third direction 3 and the second direction 2 are perpendicular to each other, and the first and third directions 1, 3 are each other In the opposite direction of 180 degrees.

The second type electrode 170 is formed on the second type semiconductor layer 140 and includes a second body portion 1710 and a third extension portion 1711. The third extending portion 1711 is located between the second and fourth extending sections 1511b, 1512b and extends from the second body portion 1710 toward the fourth direction 4, the fourth direction 4 and the second direction 2 180 degrees opposite to each other.

a first projection of the third extension 1711 on a plane 112 The projections and the second and third projections of the second extension section 1511b and the fourth extension section 1512b on the plane 112 only partially overlap in the first and third directions 1, 3 . In detail, the substrate 110 has a flat surface that defines the plane 112. If the first projection of the third extension 1711 on the plane 112 and the second projection of the second extension section 1511b on the plane 112 are observed along the line of sight of the first direction 1, they only partially overlap. Moreover, if the first projection of the third extending portion 1711 on the plane 112 and the third projection of the fourth extending portion 1512b on the plane 112 are observed along the line of sight of the third direction 3, only partial overlap .

In this embodiment, the first type electrode may be an N type, and the second type electrode is a P type. In another embodiment, the first type electrode may also be a P type, and the second type electrode may also be an N type. When the first type electrode is of the N type and the second type of electrode is of the P type, the general electron is moved from the lower side of the N type electrode to the P type electrode, and the hole is oppositely from the P type electrode to the N type electrode. mobile. When electrons and holes are combined in the luminescent layer, energy is released to emit light. The electrons and holes have the lowest path of resistance between the P-type electrode and the N-type electrode as the main moving path.

Since the first type electrode 150 includes the first extending portion 1511 and the second extending portion 1512, the second type electrode 170 includes the third extending portion 1711, thereby increasing the moving path of the electrons and the holes, even if The diffusion of electrons and holes is more uniform to avoid the concentration of heat generated and to reduce luminous efficiency and reliability. Furthermore, the first projection of the third extension portion 1711 and the second extension of the second extension portion 1511b and the fourth extension portion 1512b The third projections only partially overlap, so that the second extension portion 1511b and the fourth extension portion 1512b can be used to diffuse the current of the third extension portion 1711 to both sides to avoid a current concentration point, thereby improving static electricity. Protection ability to reduce component failure. In addition, since the first projection of the third extending portion 1711 and the second and third projections of the second extended portion 1511b and the fourth extended portion 1512b only partially overlap, the third extending portion 1711, the first The uncovered area of the second extension section 1511b and the fourth extension section 1512b can still serve as a light-emitting area.

[Embodiment 2]

Referring to FIGS. 5a and 5b, in the second embodiment, the second electrode 170 further includes a plurality of fourth extending portions 1712, and the fourth extending portions 1712 are also located in the second and fourth extending portions 1511b. Between 1512b. The fourth extensions 1712 are each independently extended by the second body portion 1710 toward a fifth linear direction 5 between the fourth direction 4 and the first direction 1 and the orientation direction is in the fourth direction 4 And a sixth straight line direction 6 between the third direction 3 extends.

Since the second electrode 170 further includes the fourth extending portion 1712, the moving path of the electrons and the holes can be further increased, and even if the diffusion of the electrons and the holes is more uniform, the concentrated heat is generated to reduce the luminous efficiency and Reliability.

[Embodiment 3]

Referring to Figures 6a, 6b and 7, a semiconductor light emitting device 200 in accordance with a third embodiment of the present invention is shown. The semiconductor light emitting device 200 can be a light emitting device Polar body. The semiconductor light-emitting device 200 includes a substrate 210, a first-type semiconductor layer 220, a light-emitting layer 230, a second-type semiconductor layer 240, a first-type electrode 250, and a second-type electrode 270. The first type semiconductor layer 220 is formed on the substrate 210. The light emitting layer 230 and a second type semiconductor layer 240 are sequentially formed on a portion of the first type semiconductor layer 220, and a portion of the first type semiconductor layer 220 is exposed.

The first type electrode 250 is formed on the bare first type semiconductor layer 220, and includes a first body portion 2510 and a first extending portion 2511. The first extending portion 2511 is from the first body portion 2510. Extending 1' to the first direction.

The second type electrode 270 is formed on the second type semiconductor layer 240, and includes a second body portion 2710 and a second extending portion 2711. The second extending portion 2711 is from the second body portion 2710 to the second portion. The direction 2' extends, and the first direction 1' and the second direction 2' are 180 degrees opposite to each other.

a first projection of the first extension 2511 on a plane 212 and a second projection of the second extension 2711 on the plane 212 are perpendicular to the first direction 1' and the second One of the directions 2' is observed in the third direction 3' only partially overlapping. In detail, the substrate 210 has a flat surface that defines the plane 212. If the first projection of the second extension 2711 on the plane 212 and the second projection of the first extension 2511 on the plane 212 are observed along the line of sight 3' in the third direction, they only partially overlap.

The first body portion 2510 of the first electrode 250 and the second body portion 2710 of the second electrode 270 may be disposed diagonally. In this embodiment, the first type electrode may be an N type, and the second type electrode is a P type. In another embodiment, the first type electrode may also be a P type, and the second type electrode may also be an N type. When the first type electrode is of the N type and the second type of electrode is of the P type, the general electron is moved from the lower side of the N type electrode to the P type electrode, and the hole is oppositely from the P type electrode to the N type electrode. mobile. When electrons and holes are combined in the luminescent layer, energy is released to emit light. The electrons and holes have the lowest path of resistance between the P-type electrode and the N-type electrode as the main moving path.

Since the first type electrode 250 includes the first extension portion 2511, the second type electrode 270 includes the second extension portion 2711, thereby increasing the moving path of electrons and holes, and even the diffusion of electrons and holes. More uniform to avoid the concentration of heat generated to reduce luminous efficiency and reliability. Furthermore, since the first projection of the first extending portion 2511 and the second projection of the second extending portion 2711 only partially overlap, the current of the second extending portion 2711 can be used to the side by the first extending portion 2511. Diffusion to avoid the occurrence of current concentration points, thereby improving the electrostatic protection capability and reducing component failure. In addition, since the first projection of the first extending portion 2511 and the second projection of the second extending portion 2711 only partially overlap, the uncovered area of the first extending portion 2511 and the second extending portion 2711 can still be used as a light. area.

[Embodiment 4]

Referring to Figures 8a and 8b, in a fourth embodiment, the second type electrode 270 Further included is a third extension portion 2721 extending from the second body portion 2710 toward the third direction 3', wherein the third direction 3' is perpendicular to the first direction 1' and the second direction 2', respectively. The second electrode 270 may further include one or more fourth extending portions 2713, and the second body portion 2710 is oriented in a fourth direction 4 between the second direction 2' and the third direction 3'. 'extend.

Since the second type electrode 270 further includes the third extension portion 2712, or the second type electrode 270 further includes the fourth extension portion 2713, the moving path of the electron and the hole can be further increased, and even the electron and the hole The diffusion is more uniform to avoid the concentration of heat generated and reduce the luminous efficiency and reliability.

In the above, it is merely described that the present invention is an embodiment or an embodiment of the technical means for solving the problem, and is not intended to limit the scope of implementation of the present invention. That is, the equivalent changes and modifications made in accordance with the scope of the patent application of the present invention or the scope of the invention are covered by the scope of the invention.

1‧‧‧First direction

2‧‧‧second direction

3‧‧‧ third direction

4‧‧‧ fourth direction

5‧‧‧ fifth direction

6‧‧‧ sixth direction

1’‧‧‧First direction

2’‧‧‧second direction

3’‧‧‧ third direction

4’‧‧‧ fourth direction

10‧‧‧Lighting diode

11‧‧‧N type semiconductor layer

12‧‧‧P type semiconductor layer

14‧‧‧N type electrode

15‧‧‧P type electrode

16‧‧‧Lighting layer

17‧‧‧Substrate

1 is a schematic plan view of a conventional light-emitting diode; FIG. 2 is a schematic cross-sectional view taken along line 2-2' of FIG. 1, and FIGS. 3a and 3b are schematic plan views of a semiconductor light-emitting device according to a first embodiment of the present invention; Figure 4 is a schematic cross-sectional view taken along line 4-4' of Figure 3a; Figures 5a and 5b are schematic plan views of a semiconductor light-emitting device according to a second embodiment of the present invention; Figures 6a and 6b are third embodiments of the present invention; FIG. 7 is a schematic cross-sectional view taken along line 7-7' of FIG. 6a; and FIGS. 8a and 8b are plan views of a semiconductor light-emitting device according to a fourth embodiment of the present invention.

100. . . Semiconductor light emitting device

120. . . First type semiconductor layer

140. . . Second type semiconductor layer

150. . . First type electrode

1510. . . First body

1511. . . First extension

1511a. . . First extension

1511b. . . Second extension

1512. . . Second extension

1512a. . . Third extension

1512b. . . Fourth extension

170. . . Second type electrode

1710. . . Second body

1711. . . Third extension

Claims (8)

A semiconductor light emitting device comprising: a substrate; a first type semiconductor layer formed on the substrate; a light emitting layer and a second type semiconductor layer are sequentially formed on a portion of the first type semiconductor layer, and the exposed portion The first type of semiconductor layer is formed on the bare first type semiconductor layer, and includes a first body portion, a first extending portion and a second extending portion, the first extending portion The first extending portion extends from the first body portion in a first direction and a second extending portion connects the first extending portion and extends in a second direction, and the second extending portion includes a third portion The extension section extends from the first body portion in a third direction, and a fourth extension section connects the third extension section and extends in a second direction, wherein the second and fourth extension sections are parallel to each other, The first direction and the third direction and the second direction are perpendicular to each other, and the first and third directions are 180 degrees opposite to each other; and a second type electrode is formed on the second type semiconductor layer Which includes one a second body portion and a third extension portion, wherein the third extension portion is located between the second and fourth extension portions, and extends from the second body portion toward the fourth direction, the fourth direction And the second direction is opposite to each other by 180 degrees, the first projection of the third extension on a plane and the second extension of the second extension section and the fourth extension section on the plane The third projection is only partially overlapped as viewed in the first and third directions; The second type electrode further includes a plurality of fourth extending portions, the fourth extending portions are also located between the second and fourth extending portions, and the fourth extending portions are independently separated by the second body portion And extending in a fifth straight direction between the fourth direction and the first direction, and extending in a sixth straight direction between the fourth direction and the third direction. The semiconductor light-emitting device of claim 1, wherein the first type electrode is of a P type and the second type of electrode is of an N type. The semiconductor light-emitting device of claim 1, wherein the first type electrode is of an N type and the second type of electrode is of a P type. A semiconductor light emitting device comprising: a substrate; a first type semiconductor layer formed on the substrate; a light emitting layer and a second type semiconductor layer are sequentially formed on a portion of the first type semiconductor layer, and the exposed portion The first type of semiconductor layer is formed on the bare first type semiconductor layer, and includes a first body portion and a first extension portion, wherein the first extension portion is from the first The body portion extends in a first direction; and a second type electrode is formed on the second type semiconductor layer, and includes a second body portion and a second extension portion, the second extension portion is from the second body Extending in a second direction, and the first direction and the second direction are opposite to each other by 180 degrees, wherein the first projection of the first extension on a plane and the second extension are at the plane The second projection is perpendicular to the first direction and the second One of the directions is only partially overlapped in the third direction; wherein the first body portion of the first electrode and the second body portion of the second electrode are disposed diagonally. The semiconductor light-emitting device of claim 4, wherein the second-type electrode further comprises a third extension portion extending from the second body portion in the third direction, wherein the third direction is respectively associated with the third One direction and the second direction are perpendicular to each other. The semiconductor light emitting device of claim 5, wherein the second type electrode further comprises one or more fourth extensions, the second body portion being oriented in the second direction and the third direction The fourth direction extends between. The semiconductor light-emitting device according to any one of claims 4 to 6, wherein the first type electrode is of a P type and the second type of electrode is of an N type. The semiconductor light-emitting device according to any one of claims 4 to 6, wherein the first type electrode is of an N type and the second type of electrode is of a P type.