SEMICONDUCTOR STRUCTURE
A semiconductor structure includes a carrier, a bonding structure, a semiconductor stack, a supporting element and a bridge layer. The bonding structure is on the carrier and has an upper surface. The semiconductor stack is on the bonding structure. The supporting element is on the bonding structure and has a side wall. The bridge layer has a first portion directly connected to the supporting element, a second portion connected to the first portion and a third portion connected to the second portion. The second portion and the third portion of the bridge layer are suspended above the upper surface of the bonding structure. The first portion of the bridge layer directly contacts the side wall of the supporting element.
This application is a continuation of U.S. patent application Ser. No. 16/549,822, filed Aug. 23, 2019, which claims the right of priority based on TW Application Serial No. 107130027, filed on Aug. 28, 2018, and the contents of which are hereby incorporated by reference in its entirety.
FIELD OF DISCLOSUREThe present disclosure relates to a semiconductor structure which may include a light-emitting diode and in particular to a semiconductor device for transferring a light-emitting diode.
BACKGROUND OF THE DISCLOSURELight-emitting diodes (LEDs) have advantages such as low energy consumption, low heat production, long operating lifetime, strong collision resistance, small size and quick speed of response, and are widely used in various fields where a lighting device is needed, for example, vehicles, home appliances, displays and light fixtures.
Since a light-emitting diode may generate a monochromatic light, it can be used for forming a pixel in a display. For example, pixels in an out-door display or an in-door display. Recently, increasing the display resolution has become a trend in developing display technologies. In order to increase the resolution, transferring more LEDs (or pixels) onto a target substrate may be required, and some technical problems are remained to be solved.
SUMMARY OF THE DISCLOSUREA semiconductor structure includes a carrier having a surface, a supporting element, a semiconductor stack and a bridge layer. The supporting element is on the surface. The semiconductor stack is on the surface and has a side surface. The bridge layer includes a first portion connecting to the supporting element, a second portion, and a third portion connecting to the semiconductor stack. The second portion is extended from the third portion toward the first portion and is protruded from the side surface.
A semiconductor structure includes a bridge layer and a semiconductor stack. The bridge layer includes a first connecting portion and a second connecting portion. The semiconductor stack is on the first connecting portion and has a side surface and comprising an active layer. The first connecting portion has a first length. The second connecting portion has a second length less than the first width. The second connecting portion is extended from the first connecting portion and is protruded from the side surface.
A semiconductor structure includes a carrier having a surface, a plurality of semiconductor devices, a supporting element, a semiconductor stack and a bridge layer. The plurality of semiconductor devices is on the surface. The semiconductor devices form an array. Each of the semiconductor devices includes a supporting element, a semiconductor stack having a side surface, and a bridge layer. The bridge layer has a first portion connecting to the supporting element, a second portion, and a third portion connecting to the semiconductor stack. The second portion is extended from the third portion toward the first portion. The second portion is protruded from the side surface.
A semiconductor structure includes a carrier, a bonding structure, a semiconductor stack, a supporting element and a bridge layer. The bonding structure is on the carrier and has an upper surface. The semiconductor stack is on the bonding structure. The supporting element is on the bonding structure and has a side wall. The bridge layer has a first portion directly connected to the supporting element, a second portion connected to the first portion and a third portion connected to the second portion. The second portion and the third portion of the bridge layer are suspended above the upper surface of the bonding structure. The first portion of the bridge layer directly contacts the side wall of the supporting element.
A semiconductor structure includes a carrier, a bonding structure and a plurality of semiconductor devices. The bonding structure is on the carrier and having an upper surface. The plurality of semiconductor devices is on the upper surface of the carrier and forms an array. Each of the plurality of semiconductor devices includes a semiconductor stack, a supporting element and a bridge layer. The semiconductor stack is on the bonding structure. The supporting element is on the bonding structure and has a side wall. The bridge layer has a first portion directly connected to the supporting element, a second portion connected to the first portion and a third portion connected to the second portion. The second portion and the third portion of the bridge layer are suspended above the upper surface of the bonding structure. The first portion of the bridge layer directly contacts the side wall of the supporting element.
The following embodiments will be described with accompany drawings to disclose the concept of the present disclosure. In the drawings or description, same or similar portions are indicated with same numerals. Furthermore, a shape or a thickness of a component in the drawings may be enlarged or reduced. Particularly, it should be noted that a component which is not illustrated or described in drawings or description may be in a form that is known by a person skilled in the art. To describe the present disclosure in a clear and concise manner, repeated descriptions of same or similar elements may be omitted in the embodiments.
The carrier 1 may support the semiconductor light-emitting device 2 and may also support other stacks or structures formed on the carrier 1. A material of the carrier 1 may include metal, oxide, semiconductor, diamond-like carbon (DLC) film, graphite, carbon fiber, or matrix composite. The carrier 1 may have a thickness of 200 μm or more, such that the carrier 1 can endure a stress generated in a manufacturing process for the semiconductor device 100 or in a pick-up process of a plurality of semiconductor light-emitting devices 2. The pick-up process of the semiconductor light-emitting devices 2 is described in later paragraphs.
The bonding structure 6 may cover the carrier 1 and the plurality of supporting elements 4 which forms an array may be fixed by the bonding structure 6. The bonding structure 6 may include a single layer or multiple layers and may have a thickness between 1 μm and 10 μm. The bonding structure 6 may include an organic material or an inorganic material. The organic material may include BCB, COC, fluorocarbon polymer, PI, or PFCB. The inorganic material may include oxide, nitride or metal. For example, the oxide includes aluminum oxide (AlxO), silicon oxide (SiOx), indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium zinc oxide (GZO), zinc oxide (ZnO), gallium phosphide (GaP), indium cerium oxide (ICO), indium tungsten oxide (IWO), indium titanium oxide (InTiO), indium zinc oxide (IZO), indium gallium oxide (IGO), gallium and aluminum co-doped zinc oxide (GAZO) or a combination thereof. The nitride may include silicon nitride (SiNx) or aluminum nitride (AlNx). The metal may include In, Ti, Pt, W, Cu, Al, Sn, Au, Ag, Pb, Ni or an alloy thereof.
In an embodiment, the bonding structure 6 includes a first diffusion barrier layer, a second diffusion barrier layer, and an alloy layer located between the first diffusion barrier layer and the second diffusion barrier layer (not shown). The alloy layer may include In, Ti, Cu, Al, Sn, Au, Ag, Pb, or Ni. The first diffusion barrier layer and the second diffusion barrier layer may include Ti, Pt, W, or an alloy thereof. The diffusion of a material in the alloy layer to the carrier 1 and/or the supporting element 4 may be prevented by the presence of the first diffusion barrier layer and/or the second diffusion barrier layer. In another embodiment, the bonding structure 6 may be a transparent structure and may be composed of a single layer or multiple layers.
A material of the supporting element 4 may include metal, oxide or nitride. In this embodiment, the material of the supporting element 4 includes Au, Cr, or the alloy thereof (Au/Cr). The supporting element 4 may have a thickness between 1 μm and 11 μm. The first part 41 of the supporting element 4 may have a thickness less than a thickness of the bonding structure 6. Specifically, the thickness of the first part 41 may be less than 1 μm, and the thickness of the second part 42 that is protruded from the surface 6S may be in a range of 1 μm to 10 μm.
Referring to
In a subsequent pick-up process, an external force can be applied on the semiconductor light-emitting device 2 to break the bridge layer 3, such that the semiconductor light-emitting device 2 may be separated from the supporting element 4. Then, the semiconductor light-emitting device 2 may be placed on another carrier for forming a display device. Specifically, when a pulling force is applied on the semiconductor light-emitting device 2, the second portion 32 may break easily since the first portion 31 is connected to the supporting element 4, the thickness T of the second portion 32 is less than the length L2, and/or the length L2 is less than length L1, such that the third portion 33 can also be picked up along with the semiconductor light-emitting device 2. As shown in
In another embodiment, the picked semiconductor light-emitting device 2 and the third portion 33 forms a light-emitting unit which can be further placed on a carrier. In other words, the light-emitting unit does not include the second portion 32 of the bridge layer 3. Similarly, an etching process can be optionally performed to remove the bridge layer in the light-emitting unit (for example, the third portion 33).
A material of the bridge layer 3 may include oxide or nitride. The oxide may include aluminum oxide (AlxO), silicon oxide (SiOx), indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), cadmium tin oxide (CTO), antimony tin oxide (ATO), aluminum zinc oxide (AZO), zinc tin oxide (ZTO), gallium zinc oxide (GZO), zinc oxide (ZnO), gallium phosphide (GaP), indium cerium oxide (ICO), indium tungsten oxide (IWO), indium titanium oxide (InTiO), indium zinc oxide (IZO), indium gallium oxide (IGO), gallium and aluminum co-doped zinc oxide (GAZO) or a combination thereof. The nitride may include silicon nitride (SiNx) or aluminum nitride (AlNx).
The semiconductor light-emitting device 2 may be located on the bridge layer 3 and directly connected to the third portion 33. The semiconductor light-emitting device 2 may include a semiconductor stack. The semiconductor stack may include a first semiconductor layer 21 on the third portion 33, an active layer 22 on the first semiconductor layer 21, and a second semiconductor layer 23 on the active layer 22. A portion of the first semiconductor layer 21 may be exposed from the second semiconductor layer 23 and the active layer 22. A first electrode 2a may be located on the first semiconductor layer 21, and a second electrode 2b may be located on the second semiconductor layer 23. The first semiconductor layer 21 and the second semiconductor layer 23 are of different conductivity types, so as to respectively provide electrons and holes. A recombination process of electrons and holes may occur in the active layer 22 and a light can be emitted. When the first semiconductor layer 21 includes a p-type III-V semiconductor material, the second semiconductor layer 23 includes an n-type III-V semiconductor material. When the second semiconductor layer 23 includes a p-type III-V semiconductor material, the first semiconductor layer 21 includes an n-type semiconductor material. The first semiconductor layer 21 or the second semiconductor layer 23 may include a dopant such as Zn, C, or Mg, so as to form a p-type semiconductor material. The first semiconductor layer 21 or the second semiconductor layer 23 may include a dopant such as Si or Te, so as to form an n-type semiconductor material. A concentration of the dopant may be between 5×1016 cm-3 and 5×1019 cm-3.
In an embodiment, a thickness of the first semiconductor layer 21 is between 0.1 μm and 2 μm, preferably between 0.1 μm and 1.5 μm. A thickness of the second semiconductor layer 23 may be between 0.1 μm and 2 μm, preferably between 0.1 μm and 1.5 μm. A total thickness of the first semiconductor layer 21, the active layer 22, and the second semiconductor layer 23 may be between 1 μm and 10 μm, preferably between 1 μm and 5 μm, so as to comply with a specification required for a downstream application such as pixels for a display. The active layer 22 may include a plurality of well layers and barrier layers alternately stacked with each other. The well layer and the barrier layer may include an III-V semiconductor material. Based on the material of the well layer, the semiconductor light-emitting device 2 may emit an infrared light with a peak wavelength between 700 nm and 1700 nm, a red light with a peak wavelength between 610 nm and 700 nm, a yellow light with a peak wavelength between 530 nm and 570 nm, a green light with a peak wavelength between 490 nm and 550 nm, a blue light or a deep blue light with a peak wavelength between 400 nm and 490 nm, or a UV light with a peak wavelength between 250 nm and 400 nm. A light exit surface 231 of the second semiconductor layer 23 may be a roughened surface (not shown) so as to reduce total internal reflection and to improve a luminous efficiency of the semiconductor light-emitting device 2.
In practical application, the sacrificial layer 5 can be removed by a dry etching (such as gas etching) or a wet etching process, such that the second portion 32 and the third portion 33 of the bridge layer 3 can be suspended above the surface 6S of the bonding structure 6, then a pick-up process may be performed. After removing the sacrificial layer 5, the surface 6S of the bonding structure 6 and the second part 42 of the supporting element 4 may be exposed. The final structure may be referred to the structure of the semiconductor device 100.
Since the production of the semiconductor device 100 and the pick-up process of the semiconductor light-emitting device 2 may be performed in different places, the sacrificial layer 5 can support the semiconductor light-emitting device 2 on the third portion 33 of the bridge layer 3, so as to avoid the detachment of the semiconductor light-emitting device 2 resulting from break of the second portion 32 due to vibrations generated during transportation of the semiconductor device 100. The material of sacrificial layer 5 may be different from the semiconductor light-emitting device 2, the bridge layer 3, the bonding structure 6, or the carrier 1, such that damages to the semiconductor light-emitting device 2, the bridge layer 3, the bonding structure 6, or the carrier 1 can be prevented in the process of removing the sacrificial layer 5. For example, the sacrificial layer 5 may be selectively etched by a solid-state or liquid-state etchant. In this embodiment, the material of sacrificial layer 5 includes silicon (Si) or zinc oxide (ZnO). The etchant may include HNO3, HF, CO3COOH or a mixture thereof.
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A patterning step can be performed on the first layer 3E to form a patterned first layer and expose the upper surface 51 of the sacrificial layer 5, as shown in the semiconductor device 200 of
In an embodiment, the sacrificial layer 5 can be further removed by dry etching (such as gas etching) or wet etching, so as to form the semiconductor device 100 as shown in
Since the production of the semiconductor device 300 and the pick-up process of the semiconductor light-emitting device 2 may be performed in different places, the sacrificial layer 5 can support the semiconductor light-emitting device 2 on the third portion 33 of the bridge layer 3, so as to avoid the detachment of the semiconductor light-emitting device 2 resulting from break of the second portion 32 due to vibrations generated during transportation of the semiconductor device 100. The material of sacrificial layer 5 may be different from the semiconductor light-emitting device 2, the bridge layer 3, the bonding structure 6 or the carrier 1, such that damages to the semiconductor light-emitting device 2, the bridge layer 3, the bonding structure 6 or the carrier 1 can be prevented in a process of removing the sacrificial layer 5. For example, the sacrificial layer 5 may be selectively etched by a solid-state or liquid-state etchant. In this embodiment, the material of sacrificial layer 5 includes silicon (Si) or zinc oxide (ZnO). The etchant may include HNO3, HF, CO3COOH or a mixture thereof.
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In an embodiment, the sacrificial layer 5 can be further removed by dry etching (such as gas etching) or wet etching, so as to form the semiconductor device 300 as shown in
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Based on above, by connecting a plurality of supporting elements 4 to the semiconductor light-emitting device 2, the force for supporting the semiconductor light-emitting device 2 through the supporting element 4 can be strengthened, and the stability of the semiconductor device can be elevated.
It should be realized that each of the embodiments mentioned in the present disclosure is only used for describing the present disclosure, but not for limiting the scope of the present disclosure. Any obvious modification or alteration is not departing from the spirit and scope of the present disclosure. Same or similar components in different embodiments or components having the same numerals in different embodiments may have same physical or chemical characteristics. Furthermore, above-mentioned embodiments can be combined or substituted under proper condition and are not limited to specific embodiments described above. A connection relationship between a specific component and another component specifically described in an embodiment may also be applied as claimed in the present disclosure. in another embodiment and is within the scope
Claims
1. A semiconductor structure, comprising:
- a carrier;
- a bonding structure on the carrier and having an upper surface;
- a semiconductor stack on the bonding structure;
- a supporting element on the bonding structure and having a side wall; and
- a bridge layer having a first portion directly connected to the supporting element, a second portion connected to the first portion and a third portion connected to the second portion;
- wherein the second portion and the third portion of the bridge layer are suspended above the upper surface of the bonding structure, and the first portion of the bridge layer directly contacts the side wall of the supporting element.
2. The semiconductor structure of claim 1, wherein the semiconductor stack is overlapped with the third portion of the bridge layer.
3. The semiconductor structure of claim 1, wherein the semiconductor stack is not overlapped with the second portion of the bridge layer.
4. The semiconductor structure of claim 1, wherein the semiconductor stack comprises a first semiconductor layer, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer.
5. The semiconductor structure of claim 4, wherein the active layer is not overlapped with the first portion and the second portion of the bridge layer.
6. The semiconductor structure of claim 1, wherein the bonding structure includes BCB, COC, fluorocarbon polymer, PI, PFCB, oxide, nitride or metal.
7. The semiconductor structure of claim 1, wherein the bridge layer includes oxide or nitride.
8. The semiconductor structure of claim 1, further comprising a sacrificial layer between the bonding structure and the bridge layer.
9. The semiconductor structure of claim 1, wherein the supporting element has a first part having a first side wall and a second part having a second side wall under the first side wall, and the first portion of the bridge layer covers the first side wall without covering the second side wall.
10. The semiconductor structure of claim 1, further comprising a first electrode and a second electrode connected to the semiconductor stack.
11. The semiconductor structure of claim 10, wherein the first electrode and the second electrode are suspended above the upper surface of the bonding structure.
12. The semiconductor structure of claim 10, wherein the first electrode and the second electrode are disposed at the same side of the semiconductor stack.
13. The semiconductor structure of claim 1, wherein the semiconductor stack has a side surface, and the second portion of the bridge layer is protruded from the side surface of the semiconductor stack.
14. The semiconductor structure of claim 1, wherein the first portion of the bridge layer has a first width and the second portion of the bridge layer has a second width less than the first width.
15. The semiconductor structure of claim 1, wherein the first portion of the bridge layer has a first width and the third portion of the bridge layer has a third width larger than the first width.
16. The semiconductor structure of claim 1, wherein the first portion of the bridge layer has a first length and the second portion of the bridge layer has a second length less than the first length.
17. The semiconductor structure of claim 1, wherein the bridge layer has a first thickness and the supporting element has a second thickness larger than the first thickness.
18. The semiconductor structure of claim 1, wherein the bridge layer has a first thickness and the semiconductor stack has a third thickness larger than the first thickness.
19. The semiconductor structure of claim 1, wherein the semiconductor stack is suspended above the upper surface of the bonding structure.
20. A semiconductor structure, comprising:
- a carrier;
- a bonding structure on the carrier and having an upper surface; and
- a plurality of semiconductor devices on the upper surface of the carrier and forming an array, and each of the plurality of semiconductor devices comprising:
- a semiconductor stack on the bonding structure;
- a supporting element on the bonding structure and having a side wall; and
- a bridge layer having a first portion directly connected to the supporting element, a second portion connected to the first portion and a third portion connected to the second portion;
- wherein the second portion and the third portion of the bridge layer are suspended above the upper surface of the bonding structure, and the first portion of the bridge layer directly contacts the side wall of the supporting element.
Type: Application
Filed: Dec 14, 2021
Publication Date: Mar 31, 2022
Inventors: Yung-Fu CHANG (Hsinchu), Fan-Lei WU (Hsinchu), Shih-Chang LEE (Hsinchu), Wen-Luh LIAO (Hsinchu), Hung-Ta CHENG (Hsinchu), Chih-Chaing YANG (Hsinchu), Yao-Ru CHANG (Hsinchu), Yi HSIAO (Hsinchu), Hsiang CHANG (Hsinchu)
Application Number: 17/550,449