TWM466359U - Light emitting diode device - Google Patents

Abstract

A light emitting diode device comprises a light-emitting stack, a first electrode, a second electrode, and a first current blocking layer. The first electrode is electrically connected to and formed on an upper surface of the light-emitting stack. The second electrode is formed on the upper surface, and the first electrode and the second electrode are electrically connected to two semiconductor layers having different conductivity types of the light-emitting stack. The first current blocking layer is formed on the upper surface of the light-emitting stack and under the first electrode. The first current blocking layer comprises a first end and a second end, respectively close to the first electrode and the second electrode. A width of the first current blocking layer is increased at a direction from the first end to the second end.

Description

Light-emitting diode device

The present invention provides a light-emitting diode device, especially a light-emitting diode device having better current diffusivity and uniformity of light emission.

With the advancement of technology, red, green and yellow light-emitting diodes have a relatively high brightness and have been mass-produced. However, blue light-emitting diodes still have bottlenecks due to epitaxial technology and material properties.

In addition, the current trend of the conventional horizontal light-emitting diode is the flow path of the shortest path, and the current flows from the positive electrode to the negative electrode. Generally, a current blocking layer is selectively disposed under the positive electrode, and a transparent conductive layer is coated on the outside of the current blocking layer. When current flows from the positive electrode to the negative electrode via the transparent conductive layer, light can be emitted from the transparent conductive layer to provide an illumination source.

However, the conventional current blocking layer is liable to cause uneven distribution of the traveling current in the transparent conductive layer, so that the light source is concentrated around the electrode, thereby making the light emitting efficiency of the light emitting diode poor. Therefore, how to improve the shortcoming of the current distribution of the conventional light-emitting diode is one of the development topics of the current related lighting industry.

The above-described light emitting diode can be further connected to other elements to form a light emitting device. The light emitting diode can be connected to the primary carrier by the side having the substrate, or can be soldered A material or a glue is formed between the secondary carrier and the light emitting diode to form a light emitting device. In addition, the secondary carrier may further include a circuit electrically connected to the electrode of the light emitting diode through a conductive structure such as a metal wire.

The patent application scope of the present invention discloses a light emitting diode device comprising: a light emitting laminate having an upper surface; a first electrode electrically connected to the light emitting layer and formed on the upper surface; a second electrode is formed on the upper surface, and the first electrode and the second electrode are electrically connected to the different electrical semiconductor layers of the light emitting layer respectively; and a first current blocking layer is formed on the light emitting layer The upper surface is located below the first electrode, the first current blocking layer has a first end and a second end, and the first end and the second end are respectively closer to the first electrode and the second electrode, and the first current blocking layer is A width gradually increases from the first end to the second end.

10‧‧‧Lighting diode device

12‧‧‧Lighting laminate

121‧‧‧ upper surface

14‧‧‧First electrode

16‧‧‧second electrode

18‧‧‧First current blocking layer

Sections 18a, 18b, 18c‧‧

181‧‧‧ first end

182‧‧‧ second end

20‧‧‧Substrate

22‧‧‧Extended electrode

24‧‧‧Transparent conductive layer

26‧‧‧Second current blocking layer

28‧‧‧First semiconductor layer

30‧‧‧Lighting layer

32‧‧‧Second semiconductor layer

D1‧‧‧width direction

D2‧‧‧Preset direction

A-A’‧‧‧ hatching

B-B’‧‧‧ hatching

C-C’‧‧‧ hatching

H1, H2, H3‧‧‧ height

W1, W2, W3, W4, W5‧‧‧ width

Fig. 1 is a top view of the light-emitting diode device of the present embodiment.

Fig. 2 is a cross-sectional view of the light-emitting diode device of the present embodiment taken along line A-A' of Fig. 1.

Fig. 3 is a cross-sectional view of the light-emitting diode device of the present embodiment taken along line B-B' of Fig. 1.

Fig. 4 is a cross-sectional view of the light-emitting diode device of the present embodiment taken along line C-C' of Fig. 1.

Please refer to FIG. 1 and FIG. 2 . FIG. 1 is a top view of a light-emitting diode device 10 according to an embodiment of the present invention, and FIG. 2 is a second embodiment of the light-emitting diode device 10 according to the present embodiment. A cross-sectional view of the A-A' line. The light emitting diode device 10 includes a light emitting layer 12, a first electrode 14, A second electrode 16, a first current blocking layer 18, a substrate 20, an extension electrode 22, a transparent conductive layer 24, and a second current blocking layer 26. The light emitting laminate 12 has an upper surface 121. The first electrode 14 and the second electrode 16 are formed at different positions of the upper surface 121, and the first electrode 14 and the second electrode 16 are a positive electrode and a negative electrode, respectively electrically connected to the first semiconductor layer 28 of the light emitting laminate 12. And a second semiconductor layer 32. In the present embodiment, the first semiconductor layer 28 and the second semiconductor layer 32 may be a p-type semiconductor and an n-type semiconductor, respectively.

The first current blocking layer 18 is formed on the upper surface 121 of the light emitting laminate 12 and is located below the first electrode 14. The first current blocking layer 18 has opposing first and second ends 181, 182, the first end 181 being closer to the first electrode 14, and the second end 182 being closer to the second electrode 16. As shown in FIG. 1, the width of the first current blocking layer 18 is gradually increased from the first end 181 to the second end 182 (preset direction D2), that is, the width W1 of the first current blocking layer 18 near the first end 181. It will be smaller than the width W2 near the second end 182. The preset direction D2 is substantially different from the width direction D1 of the first current blocking layer 18.

The substrate 20 of the light-emitting diode device 10 typically uses a sapphire substrate because of its preferred lattice matching quality. The light emitting laminate 12 is disposed on the substrate 20. The light emitting laminate 12 can include a first semiconductor layer 28, a light emitting layer 30, and a second semiconductor layer 32. The first semiconductor layer 28 and the second semiconductor layer 32 respectively have a first electrical property and a second electrical property, and the first electrode 14 and the second electrode 16 are electrically connected to the first semiconductor layer 28 and the second semiconductor layer 32, respectively. . As shown in FIGS. 1 and 2, the upper surface 121 may include exposed surfaces of the first semiconductor layer 28 and the second semiconductor layer 32, and the height H2 of the exposed surface of the second semiconductor layer 32 is substantially lower than the first semiconductor layer. The height of the exposed surface of 28 is H1.

Further, the extension electrode 22 is connected to the first electrode 14. First current blocking layer 18 It is located directly below the extension electrode 22 and substantially parallel to the extension electrode 22. A transparent conductive layer 24 is formed on the light emitting laminate 12 and covers the first current blocking layer 18, and the first electrode 14 is disposed on the transparent conductive layer 24. The second current blocking layer 26 is a selective element disposed under the first electrode 14 and the second current blocking layer 26 is selectively connectable or separated from the first current blocking layer 18. For example, taking the authoring embodiment illustrated in FIG. 2 as an example, the second current blocking layer 26 is integrally connected to the first current blocking layer 18.

As shown in FIG. 1, the first current blocking layer 18 can have a plurality of segments, such as segments 18a, 18b, and 18c. The boundary of adjacent segments may be a stepped structure. The width of the plurality of segments of the first current blocking layer 18 is gradually increased from the first end 181 to the second end 182, so the width W2 of the segment 18c can be substantially greater than the width of the segment 18b, and the width of the segment 18b is It may be substantially larger than the width W1 of the segment 18a. The first current blocking layer 18 of the present invention is not limited to only including two or three of the foregoing two segments, that is, the first current blocking layer 18 may include more than four segments, so the implementation end thereof Depending on the design requirements, the details are not described here.

Please refer to FIG. 1 to FIG. 4 , FIG. 3 is a cross-sectional view of the LED device 10 of the present embodiment taken along line BB′ of FIG. 1 , and FIG. 4 is a schematic diagram of the light-emitting diode of the present embodiment. A cross-sectional view of the body device 10 taken along line CC' of Fig. 1. Since the transparent conductive layer 24 is coated on the outside of the first current blocking layer 18, the width W3 of the transparent conductive layer 24 may be substantially larger than the width W4 of the first current blocking layer 18; and because the width of the first current blocking layer 18 will Widening along the direction D2, the total width of the cross-sectional width of the transparent conductive layer 24 on both sides of the first current blocking layer 18 in the width direction D1 (the width W3 minus the value of the width W4) is from the first end 181 to the second End 182 is decreasing. Furthermore, the structure width W5 of the extension electrode 22 can be kept constant, so the ratio of the width of the first current blocking layer 18 to the extension electrode 22 (for example, W1/W5 with respect to W2/W5) gradually increases from the first end 181 to the second end. increase. Current blocking layer The width may be substantially between 0 and 50 millimeters (μm), and the thickness of the current blocking layer (ie, the height H3 as depicted in FIGS. 3 and 4) may be substantially between 200 angstroms and 10,000 angstroms (Å).

In detail, in the light-emitting diode device 10, the current flows from the first electrode 14 to the second electrode 16, and the current cannot be uniformly distributed to the light-emitting diode device 10 without any current dispersion treatment. The semiconductor layer, and thus the light-emitting diode device 10 utilizes the barrier of the first and second current blocking layers 18, 26 to control the current path to provide better current spreading performance of the light-emitting diode device 10. In the present creation, the first current blocking layer 18 can assume a stepped structure, meaning that the boundary between the plurality of segments has a stepped step difference. This structural feature is known from FIG. Specifically, since the segment 18c closer to the second electrode 16 has a larger structural width, current does not excessively accumulate around the second electrode 16, and this design allows the light-emitting diode device 10 to effectively disperse current. Although the width variation of the first current blocking layer 18 of the present invention along the direction of the first electrode 14 to the second electrode 16 is exemplified by a stepped structure, the outer contour of the first current blocking layer 18 may be Designed as other forms of curves, for example, the first current blocking layer 18 may be an inverted triangular tapered structure, or the segments of the first current blocking layer 18 may be curved structures having different curvatures, respectively. The current blocking layer in which the segment is gradually increased in width from the first electrode 14 to the second electrode 16 belongs to the design of the present invention.

It can be known from the prior art that the horizontal light-emitting diode has a tendency to conduct the shortest path between the two electrodes, resulting in low luminous efficiency, and the present invention can make the current into the light-emitting layer as uniform as possible by improving the structure of the current blocking layer. It is distributed in various areas of the light-emitting laminate, thereby improving the luminous efficiency (Lm/W) that can be generated per watt of the light-emitting diode device.

In addition, since the current can be evenly distributed in the light-emitting diode device, the internal voltage difference of the light-emitting diode device can be effectively reduced, thereby avoiding the light-emitting diode. The device generates an instantaneous high current that can damage the light-emitting diode device due to external electrostatic effects. In other words, the current blocking layer of the present invention having a step width variation can also enhance the electrostatic protection characteristics of the light emitting diode device.

The above descriptions are only preferred embodiments of the present invention, and all changes and modifications made by the scope of the patent application of the present invention should be covered by the present invention.

10‧‧‧Lighting diode device

121‧‧‧ upper surface

14‧‧‧First electrode

16‧‧‧second electrode

18‧‧‧First current blocking layer

Sections 18a, 18b, 18c‧‧

181‧‧‧ first end

182‧‧‧ second end

20‧‧‧Substrate

26‧‧‧Second current blocking layer

D1‧‧‧width direction

D2‧‧‧Preset direction

A-A’‧‧‧ hatching

B-B’‧‧‧ hatching

C-C’‧‧‧ hatching

W1, W2‧‧‧ width

Claims (10)

A light-emitting diode device comprising: a light-emitting layer having an upper surface; a first electrode electrically connected to the light-emitting layer and formed on the upper surface; and a second electrode formed Above the upper surface, the first electrode and the second electrode are electrically connected to different electrically conductive semiconductor layers of the light emitting layer, respectively; and a first current blocking layer is formed on the light emitting layer An upper surface of the first electrode and a second end, the first end and the second end are respectively closer to the first electrode and the second electrode, One width of the first current blocking layer is gradually increased from the first end to the second end. The illuminating diode device of claim 1, further comprising: a substrate, the illuminating laminate being disposed on the substrate. The illuminating diode device of claim 1, wherein the illuminating layer comprises a first semiconductor layer, a luminescent layer and a second semiconductor layer, wherein the first semiconductor layer and the second semiconductor layer respectively have a first An electrical and a second electrical. The illuminating diode device of claim 3, wherein the upper surface comprises a exposed surface of the first semiconductor layer and the second semiconductor layer, and a height of the exposed surface of the second semiconductor layer is substantially lower than the first The height of the exposed surface of a semiconductor layer. The illuminating diode device of claim 1, further comprising: an extension electrode connected to the first electrode, the first current blocking layer Directly below the extension electrode, and substantially parallel to the extension electrode. The light emitting diode device of claim 1, further comprising: a transparent conductive layer formed on the light emitting layer and covering the first current blocking layer, wherein the first electrode is disposed on the transparent conductive layer on. The illuminating diode device of claim 1, further comprising: a second current blocking layer disposed under the first electrode, the second current blocking layer being connected or separated from the first current blocking layer . The illuminating diode device of claim 1, wherein the first current blocking layer has a plurality of segments, and the boundary of the adjacent segments is a stepped structure. The illuminating diode device of claim 1, wherein the width of the first current blocking layer is gradually increased from the first end to the second end. The illuminating diode device of claim 5, wherein a width ratio of the first current blocking layer to the one of the extending electrodes is gradually increased from the first end to the second end.