Semiconductor structure and preparation method thereof

Abstract

The embodiment of the invention provides a semiconductor structure and a preparation method thereof. The semiconductor structure comprises a carrier plate; the light-emitting units are located on one side of the carrier plate, each light-emitting unit comprises a first light-emitting structure, a second light-emitting structure and a third light-emitting structure which are arranged at intervals along the surface of the carrier plate and have different light-emitting wavelengths, the second light-emitting structure surrounds the first light-emitting structure, and the third light-emitting structure surrounds the second light-emitting structure; the lenses are located on the sides, away from the carrier plate, of the light-emitting units, the lenses correspond to the light-emitting units respectively, light emitted by the light-emitting units is converged and subjected to color mixing through the lenses, crosstalk of the light between the different light-emitting units before the light reaches the receiver is avoided, and therefore the light-emitting effect is prevented from being reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a semiconductor structure and a method for preparing the same. Background Art

[0002] With the development of display technology, light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), and liquid crystal displays (LCDs) are widely used in electronic products such as computers, televisions, mobile phones, and wearable devices. Micro LEDs (Micro Light-emitting diodes) are an emerging technology primarily based on inorganic GaN-based LEDs. Compared with LCDs and OLEDs, Micro LEDs offer advantages such as small size, high contrast, low power consumption, and long life. However, the display quality of Micro LED display panels still needs to be improved, and the complex manufacturing process of Micro LED display panels leads to higher production costs. Summary of the Invention

[0003] In view of this, the present application provides a semiconductor structure and a method for manufacturing the same to improve the display effect of Micro LED display panels and address the problem of high production costs.

[0004] In a first aspect, the present application provides a semiconductor structure comprising: a carrier; a plurality of light-emitting units located on one side of the carrier, each light-emitting unit comprising a first light-emitting structure, a second light-emitting structure, and a third light-emitting structure spaced apart along the surface of the carrier and emitting light of different wavelengths, the second light-emitting structure surrounding the first light-emitting structure, and the third light-emitting structure surrounding the second light-emitting structure; and a plurality of lenses located on a side of the light-emitting unit facing away from the carrier, the plurality of lenses corresponding to the plurality of light-emitting units, respectively, and the lenses converging light emitted by the light-emitting units.

[0005] In a second aspect, the present application provides a method for preparing a semiconductor structure, the method comprising: forming a plurality of light-emitting units, the light-emitting units comprising a first light-emitting structure, a second light-emitting structure, and a third light-emitting structure that are arranged at intervals and have different luminous wavelengths, the second light-emitting structure surrounding the first light-emitting structure, and the third light-emitting structure surrounding the second light-emitting structure; bonding the light-emitting units to a carrier; and forming a plurality of lenses on a side of the light-emitting units facing away from the carrier, the plurality of lenses corresponding to the plurality of light-emitting units respectively, and the lenses converging light emitted by the light-emitting units.

[0006] An embodiment of the present application provides a semiconductor structure and a method for preparing the same, the semiconductor structure comprising: a carrier; a plurality of light-emitting units located on one side of the carrier, each light-emitting unit comprising a first light-emitting structure, a second light-emitting structure, and a third light-emitting structure spaced apart along the surface of the carrier and having different luminous wavelengths, the second light-emitting structure surrounding the first light-emitting structure, and the third light-emitting structure surrounding the second light-emitting structure; and a plurality of lenses located on a side of the light-emitting unit facing away from the carrier, the plurality of lenses corresponding to the plurality of light-emitting units, respectively, the lenses converging and mixing the light emitted by the light-emitting units to avoid crosstalk between light from different light-emitting units before reaching a receiver, thereby avoiding reduction in light emission effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 FIG2 is a schematic top view of a semiconductor structure provided by an embodiment of the present application;

[0008] Figure 2 Shown is Figure 1 Schematic diagram of the cross section along line AB;

[0009] Figure 3 FIG2 is a schematic cross-sectional view of a semiconductor structure provided by an embodiment of the present application;

[0010] Figure 4 FIG2 is a schematic top view of a light emitting unit provided in one embodiment of the present application;

[0011] Figure 5 FIG2 is a schematic top view of a light emitting unit provided in one embodiment of the present application;

[0012] Figure 6 FIG2 is a schematic top view of another light emitting unit provided in one embodiment of the present application;

[0013] Figure 7 FIG2 is a partial cross-sectional schematic diagram of another semiconductor structure provided by an embodiment of the present application;

[0014] Figure 8 FIG2 is a partial cross-sectional schematic diagram of another semiconductor structure provided by an embodiment of the present application;

[0015] Figure 9 FIG2 is a partial cross-sectional schematic diagram of another semiconductor structure provided by an embodiment of the present application;

[0016] Figures 10 to 18 FIG2 is a partial cross-sectional schematic diagram of an intermediate structure for forming a light-emitting unit in a method for preparing a semiconductor structure provided by an embodiment of the present application;

[0017] Figures 19 to 21FIG2 is a partial cross-sectional schematic diagram of an intermediate structure for forming a light-emitting unit in another method for preparing a semiconductor structure provided by an embodiment of the present application;

[0018] Figures 22 to 23 Shown is a partial cross-sectional schematic diagram of an intermediate structure of another method for preparing a semiconductor structure provided by an embodiment of the present application.

[0019] Description of reference numerals:

[0020] 10-carrier; 20-light-emitting unit, 21-first light-emitting structure, 22-second light-emitting structure; 23-third light-emitting structure; 30-lens; 40-first electrode layer; 41-first electrode; 43-third electrode; 44-fourth electrode; 50-second electrode layer; 51-second electrode; 60-growth substrate; 71-first dielectric layer; 72-second dielectric layer; 73-third dielectric layer; 74-fourth dielectric layer; 81-first groove; 82-second groove; 83-third groove; 84-fourth groove; 85-fifth groove; 86-sixth groove. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. It should be understood that the terms "first", "second", etc. used in this application are only used to distinguish information of the same type from each other, and are not necessarily used to describe a specific order or sequence.

[0022] The present application provides a semiconductor structure that can improve the problems of low luminous intensity and high production cost of Micro LED light-emitting devices.

[0023] Figure 1 FIG2 is a schematic top view of a semiconductor structure provided in accordance with an embodiment of the present application. Figure 2 Shown is Figure 1 Schematic diagram of the cross section along line AB. Figure 1 and Figure 2 As shown, an embodiment of the present application provides a semiconductor structure, which includes a carrier 10 , a plurality of light-emitting units 20 and a plurality of lenses 30 .

[0024] Optionally, the carrier 10 may include a silicon substrate and a driving circuit layer for driving the light-emitting unit 20 .

[0025] Optionally, a plurality of light emitting units 20 are located on one side of the carrier 10. Figure 1As shown, a plurality of light-emitting units 20 are arranged in an array. Each light-emitting unit 20 includes a first light-emitting structure 21, a second light-emitting structure 22, and a third light-emitting structure 23, which are spaced apart along the surface of the carrier 10 and emit light of different wavelengths. The second light-emitting structure 22 surrounds the first light-emitting structure 21, and the third light-emitting structure 23 surrounds the second light-emitting structure 22.

[0026] In the embodiment of the present application, the second light-emitting structure 22 surrounds the first light-emitting structure 21, and the third light-emitting structure 23 surrounds the second light-emitting structure 22. This arrangement allows the light of different wavelengths emitted by each light-emitting structure to be evenly distributed in all directions and reduces crosstalk between lights of different colors. In other words, light is evenly distributed on the light-emitting surface of the light-emitting unit 20. Furthermore, the annular structure can help relieve stress in the second and third light-emitting structures 22, 23, improving the performance of the light-emitting unit 20.

[0027] Optionally, the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 may include an N-type semiconductor layer (not shown), an active layer (not shown), and a P-type semiconductor layer (not shown) stacked in sequence. The material of the N-type semiconductor layer may be an N-type doped Group III nitride-based material. The N-type doping element may include at least one of Si, Ge, Sn, Se, or Te. The active layer may include at least one of a single quantum well structure, a multiple quantum well structure, a quantum wire structure, and a quantum dot structure. The material of the P-type semiconductor layer may be a P-type doped Group III nitride-based material. The P-type doping element may include at least one of Mg, Zn, Ca, Sr, or Ba. The Group III nitride-based material may include any one or a combination of GaN, AlGaN, InGaN, and AlInGaN.

[0028] Optionally, the first light emitting structure 21 , the second light emitting structure 22 and the third light emitting structure 23 are spaced apart from each other. Exemplarily, dielectric material is filled between the first light emitting structure 21 , the second light emitting structure 22 and the third light emitting structure 23 . For example, the dielectric material may be silicon dioxide.

[0029] Alternatively, the semiconductor structure may be a Micro LED display panel, and the light-emitting units 20 may serve as pixels in the display panel, arranged in an array. The first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 may serve as sub-pixels of the display panel. The first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 may emit blue light, green light, and red light, respectively.

[0030] A plurality of lenses 30 are located on the side of the light-emitting unit 20 away from the carrier 10, and the plurality of lenses 30 correspond to the plurality of light-emitting units 20 respectively, and the lenses 30 converge the light emitted by the light-emitting units 20. Specifically, one lens 30 is correspondingly arranged on the light-emitting side of one light-emitting unit 20, and can converge the light of different wavelengths emitted by one light-emitting unit 20, thereby achieving the purpose of color mixing and avoiding crosstalk between the light of different light-emitting units before reaching the receiver, thereby avoiding a decrease in the light-emitting effect. Optionally, when the semiconductor structure is used for display, the receiver can be a human eye, and the light emitted by the semiconductor structure is color-mixed to avoid a decrease in the display effect due to crosstalk between the light; on the other hand, it can avoid the human eye from recognizing the boundaries of light-emitting structures of different wavelengths, thereby improving the display experience.

[0031] Optionally, multiple light-emitting structures with different emission wavelengths for a single light-emitting unit 20 can be fabricated simultaneously by epitaxial growth, avoiding the complex process of subsequent mass transfer of the three RGB colors, reducing process difficulty, and thereby improving the yield of the semiconductor structure. In one embodiment, the orthographic projection of the light-emitting unit 20 on the carrier 10 is located within the orthographic projection of the corresponding lens 30 on the carrier 10. In other words, the area of ​​the orthographic projection of the lens 30 on the carrier 10 is greater than or equal to the orthographic projection of the light-emitting unit 20 on the carrier 10. When the orthographic projection of the lens 30 on the carrier 10 is equal to the area of ​​the orthographic projection of the light-emitting unit 20 on the carrier 10, the lens 30 can converge parallel light emitted by the light-emitting unit 20 to achieve color mixing. When the area of ​​the orthographic projection of the lens 30 on the carrier 10 is greater than the area of ​​the orthographic projection of the light-emitting unit 20 on the carrier 10, the lens 30 can converge light emitted obliquely from the light-emitting unit 20, thereby increasing the intensity of the light emitted from the semiconductor structure in the embodiment of the present application and improving light extraction efficiency.

[0032] Optionally, the lens 30 includes a Fresnel lens. A Fresnel lens is a special lens with a sawtooth structure that can converge scattered, wide-angle light into parallel light, and can control the light in the angle of view to a certain extent; if the light projected onto one side of the Fresnel lens is parallel light, it converges and focuses into a point. Specifically, Figure 2 As shown, a light emitting unit 20 faces a lens 30 , and the light emitting unit 20 emits light of multiple wavelengths in parallel. After passing through the lens 30 , the light is converged and focused into one point to complete color mixing, thereby improving the display effect.

[0033] Optionally, the material of the lens 30 may be a transparent material. For example, the material of the lens 30 may be a material with high light transmittance, such as an organic polymer or glass. The organic polymer may be polyolefin.

[0034] Optionally, the material of the lens 30 includes SiO 2 , GaN or AlN. The lens 30 is manufactured on the light emitting unit 20 through a semiconductor process. The process is simple and the light emitting unit 20 and the lens 30 can be integrated at one time.

[0035] Alternatively, as Figure 2 As shown, the light emitting unit 20 and the lens 30 are spaced apart by a distance.

[0036] Optionally, Figure 3 FIG. 1 is a cross-sectional view of a semiconductor structure provided by an embodiment of the present application. Figure 3 As shown, the carrier 10 includes multiple light-emitting units 20. The light from each light-emitting unit 20 is converged at an imaging position 301 through a lens 30 and then received by a receiver (such as a human eye). Specifically, the imaging position 301 can be a physical structure or refer to a convergence position of light.

[0037] In one embodiment, the center of gravity of the orthographic projection of the light-emitting unit 20 on the carrier 10 and the center of gravity of the orthographic projection of the lens 30 on the carrier 10 coincide with each other, which can improve the color mixing effect of the lens. Optionally, the center of gravity of the orthographic projection of the first light-emitting structure 21 on the carrier 10, the center of gravity of the orthographic projection of the second light-emitting structure 22 on the carrier 10, and the center of gravity of the orthographic projection of the third light-emitting structure 23 on the carrier 10 coincide with each other, which facilitates the color mixing of the lens; optionally, the center of gravity of the orthographic projection of the first light-emitting structure 21 on the carrier 10, the center of gravity of the orthographic projection of the second light-emitting structure 22 on the carrier 10, the center of gravity of the orthographic projection of the third light-emitting structure 23 on the carrier 10, and the center of gravity of the orthographic projection of the lens 30 on the carrier 10 coincide with each other, which further improves the color mixing effect of the lens.

[0038] In one embodiment, the orthographic projections of the second light emitting structure 22 and the third light emitting structure 23 on the carrier 10 are respectively ring-shaped, and the shape of the outline of the ring is the same as the shape of the outline of the first light emitting structure 21. Figure 1 As shown, the orthographic projection of the first light-emitting structure 21 on the carrier 10 is a circle, and the orthographic projections of the second light-emitting structure 22 and the third light-emitting structure 23 on the carrier 10 are respectively rings. In this case, the circular or ring-shaped light-emitting structure helps to release stress and avoid cracking during the manufacturing process or use. In another embodiment, Figure 4 FIG. 1 is a top view of a light emitting unit provided in one embodiment of the present application. Figure 4 As shown, the orthographic projection of the first light emitting structure 21 on the carrier 10 is a rectangle, and the orthographic projections of the second light emitting structure 22 and the third light emitting structure 23 on the carrier 10 are rectangular rings. In another embodiment, Figure 5 FIG. 1 is a top view of a light emitting unit provided in one embodiment of the present application. Figure 5As shown, the orthographic projection of the first light-emitting structure 21 on the carrier 10 is an ellipse, while the orthographic projections of the second light-emitting structure 22 and the third light-emitting structure 23 on the carrier 10 are each an elliptical ring. Specifically, light emitted by the light-emitting unit 20 is uniformly emitted from the center of the light-emitting unit 20 along the radial direction of the outline shape. Therefore, a display device fabricated using the semiconductor structure provided by the embodiments of the present application can achieve excellent display effects.

[0039] Optionally, the orthographic projection of the first light-emitting structure 21 on the carrier 10 is a circular, polygonal, elliptical or other special-shaped structure.

[0040] like Figure 1 As shown, in one embodiment, the orthographic projection shape of the lens 30 on the carrier 10 is the same as the orthographic projection shape of the light-emitting unit 20 on the carrier 10. For example, if the light-emitting unit 20 is circular, the lens 30 is also circular; if the light-emitting unit 20 is rectangular, the lens 30 is also rectangular. The shape of the lens 30 being the same as the shape of the light-emitting unit 20 can make the edge of the lens 30 parallel to the edge of the light-emitting unit, and parallel light is converged by the lens 30, thereby better focusing the light emitted by the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23. Optionally, the area of ​​the orthographic projection of the lens 30 on the carrier 10 is greater than or equal to the area of ​​the orthographic projection of the light-emitting unit 20 on the carrier 10.

[0041] In one embodiment, Figure 6 FIG. 1 is a top view of another light emitting unit provided in an embodiment of the present application. Figure 6 As shown, the second light emitting structure 22 includes at least two second sub-light emitting structures spaced apart; and / or, the third light emitting structure 23 includes at least two third sub-light emitting structures spaced apart. Optionally, the number of the second sub-light emitting structures may be 2, 3, 4, etc.; or the number of the third sub-light emitting structures may be 2, 3, 4, etc. Figure 6 As shown, the second sub-light emitting structure 22 includes four third light emitting sub-structures, and the third light emitting structure 23 includes eight third light emitting sub-structures. Optionally, multiple second light emitting sub-structures can be controlled separately, and multiple third light emitting sub-structures can be controlled separately to more flexibly adjust the light intensity of the light emitting structure.

[0042] In one embodiment, the light emitting unit 20 includes a first electrode layer 40 and a second electrode layer 50 .

[0043] Figure 7 FIG. 1 is a partial cross-sectional view of another semiconductor structure provided by an embodiment of the present application. Figure 7As shown, optionally, the first electrode layer 40 is located between the light-emitting unit 20 and the carrier 10, and includes first electrodes 41 electrically connected to the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23. The second electrode layer 50 is located on the side of the light-emitting unit 20 facing away from the carrier 10, and includes three second electrodes 51 electrically connected to the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23, respectively. The three second electrodes 51 are electrically isolated from each other. In other words, the first electrode 41 is a common electrode for the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23. The first electrode 41 connected to the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 can be formed in a single process, thereby improving efficiency. In this case, the carrier 10 is not the growth substrate of the light-emitting unit 20.

[0044] Optionally, a first electrode 41 shared by the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 may be provided on a side of the light-emitting unit 20 facing away from the carrier 10. Three second electrodes 51 connected to the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23, respectively, may be provided on a side of the light-emitting unit 20 facing the carrier 10.

[0045] Optionally, the materials of the first electrode 41 and the second electrode 51 may be metal materials, for example, the materials of the first electrode 41 and the second electrode 51 may be copper, silver, iron, and alloys thereof.

[0046] Optionally, Figure 8 FIG. 1 is a partial cross-sectional view of another semiconductor structure provided by an embodiment of the present application. Figure 8 As shown, the first electrode layer 40 is located between the light-emitting unit 20 and the carrier 10, and includes a third electrode 43 and a fourth electrode 44 electrically connected to the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23, respectively. The first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 each include two semiconductor film layers with different conductive types, and the third electrode 43 and the fourth electrode 44 are electrically connected to the two semiconductor film layers, respectively, so that the light output of the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 can be controlled separately.

[0047] Optionally, the electrical signals of the first electrode layer 40 and the second electrode layer 50 are controlled to achieve full color or white light display. Figure 7Taking the semiconductor structure shown in FIG. 1 as an example, a first common signal is provided to the first electrode layer 40, and different second signals are provided to the first light-emitting structure 21, the second light-emitting structure 22, and the second electrode 51 of the third light-emitting structure 23 of the plurality of light-emitting units 20. After being mixed by the lens 30, the plurality of light-emitting units 20 emit light of different wavelength ranges or different intensities, ultimately achieving full color. Specifically, Figure 7 Taking the semiconductor structure shown as an example, a first common signal is provided to the first electrode layer 40, and the same second signal is provided to the first light-emitting structure 21, the second light-emitting structure 22 and the second electrode 51 of the third light-emitting structure 23 of the multiple light-emitting units 20 respectively. After mixing through the lens 30, the multiple light-emitting units 20 emit white light, and finally realize white light.

[0048] In one embodiment, the light-emitting structure with the largest light-emitting wavelength among the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 has the largest projected area on the carrier 10. For example, when the light-emitting colors of the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 are blue, green and red respectively, the projected areas of the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 on the carrier 10 increase in sequence. Since the light extraction efficiency of different wavelengths is different, the shorter the wavelength, the stronger the light extraction efficiency. In order to improve the light extraction efficiency, the area of ​​the light-emitting structure with a larger light-emitting wavelength is increased. In addition, the human eye has different perception sensitivities to light of different wavelengths. Based on this, by designing the area ratio of different light color units, the light intensity of each light-emitting structure in the light-emitting unit 20 can be effectively balanced, and the problem of display color deviation can be improved.

[0049] Optionally, the semiconductor structure provided in this application is used to manufacture a vehicle light array.

[0050] In one embodiment, Figure 9 FIG. 1 is a partial cross-sectional view of another semiconductor structure provided by an embodiment of the present application. Figure 9 As shown, the light-emitting unit 20 includes a stacked light-emitting layer 200 and a light-conversion layer 201, with the light-conversion layer 201 located between the light-emitting layer 200 and the lens 30. The light-conversion layers 201 of the first, second, and third light-emitting structures 21, 22, and 23 are different, resulting in different emission wavelengths for the first, second, and third light-emitting structures 21, 22, and 23. Specifically, the light-emitting layer 200 of each light-emitting unit 20 emits light of the same wavelength. After passing through the different light-conversion layers 201 of the three light-emitting structures 21, 22, and 23, the light ultimately emits light of different wavelengths.

[0051] Optionally, the material of the light-conversion layer 201 can be quantum dots or phosphors. Specifically, the light-emitting layer 200 emits white, yellow, or blue light. The light-conversion layer 201 in the first light-emitting structure 21 is provided with blue quantum dots, which ultimately emits blue light; the light-conversion layer 201 in the second light-emitting structure 22 is provided with green quantum dots, which ultimately emits green light; and the light-conversion layer 201 in the third light-emitting structure 23 is provided with red quantum dots, which ultimately emits red light.

[0052] In one embodiment, the present application provides a method for preparing a semiconductor structure, which includes the following steps.

[0053] In step S1 , a plurality of light-emitting units 20 are formed. The light-emitting units 20 include a first light-emitting structure 21 , a second light-emitting structure 22 and a third light-emitting structure 23 which are arranged at intervals and have different luminous wavelengths. The second light-emitting structure 22 surrounds the first light-emitting structure 21 , and the third light-emitting structure 23 surrounds the second light-emitting structure 22 .

[0054] Step S2 , bonding the light emitting unit 20 to the carrier 10 .

[0055] In step S3 , a plurality of lenses 30 are formed on a side of the light emitting unit 20 facing away from the carrier 10 . The plurality of lenses 30 correspond to the plurality of light emitting units 20 , respectively, and the lenses 30 converge the light emitted by the light emitting units 20 .

[0056] Figures 10 to 18 FIG. 1 is a partial cross-sectional diagram of an intermediate structure of a light-emitting unit in a method for preparing a semiconductor structure provided by an embodiment of the present application. Figures 10 to 18 As shown, forming a plurality of light emitting units 20 includes the following steps.

[0057] Step 1101 : providing a growth substrate 60 .

[0058] like Figure 10 As shown, specifically, the growth substrate 60 can be made of sapphire, silicon carbide, single crystal silicon, polycrystalline silicon, diamond, gallium nitride, a composite substrate, or the like.

[0059] Step 1102 : forming a first dielectric layer 71 covering the growth substrate 60 . The first dielectric layer 71 includes a first groove 81 exposing the growth substrate 60 .

[0060] like Figure 11 As shown, specifically, the first groove 81 can be formed by etching the first dielectric layer 71 using a mask until the growth substrate 60 is exposed. The shape of the orthographic projection of the first groove 81 on the growth substrate 60 can be circular, polygonal, or elliptical, etc. Exemplarily, the shape of the orthographic projection of the first groove 81 on the growth substrate 60 is circular.

[0061] Step 1103 : epitaxially fabricate the first light emitting structure 21 in the first groove 81 .

[0062] like Figure 12 Specifically, the first light-emitting structure 21 may include an N-type semiconductor layer (not shown), an active layer (not shown), and a P-type semiconductor layer (not shown) stacked in sequence. Optionally, the first light-emitting structure 21 may further include a transparent electrode (not shown). For example, the transparent electrode may be made of ITO. Exemplarily, the first light-emitting structure 21 is configured to emit blue light.

[0063] Step 1104 : forming a second dielectric layer 72 covering the first light emitting structure 21 and the first dielectric layer 71 .

[0064] like Figure 13 As shown, specifically, the second dielectric layer 72 covers the first light emitting structure 21 to protect the first light emitting structure 21 and prevent subsequent film layers of the second light emitting structure 22 from being formed on the first light emitting structure 21 .

[0065] Step 1105 : etching the second dielectric layer 72 to form a second groove 82 surrounding the first light emitting structure 21 and exposing the growth substrate 60 .

[0066] like Figure 14 As shown, specifically, the second groove 82 can be formed by etching the second dielectric layer 72 and the first dielectric layer 71 through a mask until the growth substrate 60 is exposed. For example, the orthographic projection of the second groove 82 on the growth substrate 60 can be in the shape of a ring.

[0067] Step 1106 , epitaxially fabricate the second light emitting structure 22 in the second groove 82 .

[0068] like Figure 15 As shown, specifically, the second light emitting structure 22 is similar to the first light emitting structure 21 in structure, and the difference between the two is that the active layer is made of different materials. Optionally, the second light emitting structure 22 is used to emit green light.

[0069] Step 1107 : forming a third dielectric layer 73 covering the second light emitting structure 22 and the second dielectric layer 72 .

[0070] like Figure 16 As shown, specifically, the third dielectric layer 73 is used to prevent the subsequent film layer of the third light-emitting structure 23 from being formed above the second light-emitting structure 22 .

[0071] Step 1108 : Etch the third dielectric layer 73 to form a third groove 83 surrounding the second light emitting structure 22 and exposing the growth substrate 60 .

[0072] like Figure 17Specifically, the third groove 83 can be formed by etching the third dielectric layer 73, the second dielectric layer 72 and the first dielectric layer 71 through a mask until the growth substrate 60 is exposed. For example, the orthographic projection of the second groove 82 on the growth substrate 60 can be a ring.

[0073] Step 1109 , epitaxially fabricating a third light emitting structure 23 in the third groove 83 .

[0074] like Figure 18 As shown, specifically, the third light emitting structure 23 is similar to the first light emitting structure 21, and the difference between the two is that the active layer is made of different materials. Optionally, the second light emitting structure 22 is used to emit red light.

[0075] Optionally, after forming the third light emitting structure 23 , the first dielectric layer 71 , the second dielectric layer 72 , and the third dielectric layer 73 may be planarized to expose the first light emitting structure 21 and the second light emitting structure 22 .

[0076] Optionally, after the planarization process, a first electrode layer is formed on the surfaces of the first dielectric layer 71, the first light emitting structure 21, the second light emitting structure 22, and the third light emitting structure 23. The first electrode layer may be a first electrode shared by the first light emitting structure 21, the second light emitting structure 22, and the third light emitting structure 23.

[0077] In this embodiment, the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 with different light-emitting colors are formed on the same growth substrate 60 using an epitaxial process. Multiple light-emitting units with light-emitting structures of different colors can be bonded to the carrier as a whole. This method can simplify the preparation process of Micro LED, thereby significantly reducing the production cost of Micro LED.

[0078] Figures 19 to 21 FIG. 1 is a partial cross-sectional view of an intermediate structure of a light-emitting unit formed in another method for preparing a semiconductor structure provided by an embodiment of the present application. Figures 19 to 21 As shown, optionally, forming a plurality of light emitting units 20 includes the following steps.

[0079] Step S1201, providing a growth substrate 60. Optionally, see Figure 10 and step S1101, which will not be described again here.

[0080] Step S1202, as Figure 19 As shown, a fourth dielectric layer 7 is formed covering the growth substrate 60 .

[0081] In step S1203, the fourth dielectric layer 74 is etched to form at least one fourth groove 84, a plurality of fifth grooves 85, and a plurality of sixth grooves 86 that expose the growth substrate 60. The plurality of fifth grooves 85 surround the fourth grooves 84, and the plurality of sixth grooves 86 surround the plurality of fifth grooves 85. The fourth grooves 84, the fifth grooves 85, and the sixth grooves 86 have different projected areas on the growth substrate 60.

[0082] like Figure 20 As shown, specifically, the fourth dielectric layer can be etched using a mask. Optionally, the orthographic projection of the fourth groove 84 on the growth substrate 60 is a circle, and the orthographic projections of the fifth groove 85 and the sixth groove 86 on the growth substrate 60 can be rings.

[0083] Step S1204 , epitaxially fabricating the first light emitting structure 21 , the second light emitting structure 22 and the third light emitting structure 23 with different light emitting wavelengths in the fourth groove 84 , the fifth groove 85 and the sixth groove 86 at one time.

[0084] like Figure 21 As shown, specifically, the first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 with different emission wavelengths can be prepared in the same epitaxial process using the same process parameters. Since the sizes of the fourth groove 84, the fifth groove 85, and the sixth groove 86 are different, the materials of the active layers formed in different grooves under the same conditions are different, and the formed first light-emitting structure 21, the second light-emitting structure 22, and the third light-emitting structure 23 emit blue light, green light, and red light, respectively.

[0085] like Figure 22 As shown, in step S2 , bonding the light emitting unit 20 to the carrier 10 may include bonding a side of the light emitting unit 20 facing away from the growth substrate 60 to the carrier 10 .

[0086] like Figure 23 As shown, after the light emitting unit 20 and the carrier 10 are bonded, the original growth substrate 60 is peeled off.

[0087] Optionally, after peeling off the original growth substrate 60, a second electrode layer is formed on the side of the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23 facing away from the carrier 10, and the second electrode layer includes three second electrodes electrically connected to the first light-emitting structure 21, the second light-emitting structure 22 and the third light-emitting structure 23, respectively.

[0088] like Figure 2As shown, in step S3, a lens 30 is formed on the side of the light-emitting unit 20 facing away from the carrier 10. A distance is provided between the light-emitting unit 20 and the lens 30, which can be used to arrange electrodes and other structures. Optionally, when the lens 30 is made of materials such as SiO2, GaN, or AlN, it can be formed on the surface of the light-emitting unit 20 by deposition or epitaxy. This process is simple and allows the light-emitting unit 20 and the lens 30 to be integrated at one time. When the lens 30 is made of materials such as organic polymers or glass, it can be formed by bonding.

[0089] The embodiment of the present application provides a method for preparing a semiconductor structure, in which a first light-emitting structure, a second light-emitting structure and a third light-emitting structure of different light-emitting colors are formed on the same growth substrate and can be bonded to a carrier as a whole at the same time. Compared with the preparation method of the traditional mass transfer process in which light-emitting structures of different light-emitting colors are formed on different growth substrates and then the light-emitting structures of different colors are transferred to a carrier, the preparation method of the semiconductor structure provided by the embodiment of the present application simplifies the preparation process of Micro LED and greatly reduces the production cost of Micro LED. In the semiconductor structure prepared by the preparation method, the light-emitting unit includes a first light-emitting structure, a second light-emitting structure and a third light-emitting structure, the second light-emitting structure surrounds the first light-emitting structure, and the third light-emitting structure surrounds the second light-emitting structure. A plurality of lenses correspond to a plurality of light-emitting units respectively, and the lenses converge and mix the light emitted by the light-emitting units to avoid crosstalk between the light of different light-emitting units before reaching the receiver, thereby avoiding reduction in the light output effect.

[0090] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A semiconductor structure, characterized in that include: a carrier plate (10); a plurality of light-emitting units (20) located on one side of the carrier (10), each of the light-emitting units (20) comprising a first light-emitting structure (21), a second light-emitting structure (22), and a third light-emitting structure (23) spaced apart along the surface of the carrier (10) and emitting light of different wavelengths, the second light-emitting structure (22) surrounding the first light-emitting structure (21), and the third light-emitting structure (23) surrounding the second light-emitting structure (22); and A plurality of lenses (30) are located on a side of the light-emitting unit (20) away from the carrier (10), the plurality of lenses (30) respectively corresponding to the plurality of light-emitting units (20), and the lenses (30) converge the light emitted by the light-emitting units (20).

2. The semiconductor structure according to claim 1, wherein: The orthographic projection of the light-emitting unit (20) on the carrier (10) is located within the orthographic projection of the corresponding lens (30) on the carrier (10).

3. The semiconductor structure according to claim 2, wherein: The lens (30) comprises a Fresnel lens.

4. The semiconductor structure according to claim 3, wherein: The material of the lens (30) includes any one of SiO2, GaN, AlN, glass or organic polymer materials.

5. The semiconductor structure according to claim 2, wherein: The center of gravity of the projection of the light-emitting unit (20) on the carrier (10) coincides with the center of gravity of the projection of the lens (30) on the carrier (10). The semiconductor structure according to claim 1 , wherein: The orthographic projections of the second light-emitting structure (22) and the third light-emitting structure (23) on the carrier (10) are respectively ring-shaped, and the shape of the outline of the ring is the same as the shape of the outline of the first light-emitting structure (21).

7. The semiconductor structure according to claim 6, wherein: The orthographic projection shape of the lens (30) on the carrier (10) is the same as the orthographic projection shape of the light-emitting unit (20) on the carrier (10).

8. The semiconductor structure according to claim 6, wherein: The second light-emitting structure (22) comprises at least two second sub-light-emitting structures arranged at intervals; and / or The third light-emitting structure (23) comprises at least two third sub-light-emitting structures arranged at intervals.

9. The semiconductor structure according to claim 1, wherein: The light emitting unit (20) comprises: a first electrode layer (40), located between the light-emitting unit (20) and the carrier (10), comprising first electrodes (41) electrically connected to the first light-emitting structure (21), the second light-emitting structure (22), and the third light-emitting structure (23); The second electrode layer (50) is located on a side of the light-emitting unit (20) facing away from the carrier (10), and includes three second electrodes (51) electrically connected to the first light-emitting structure (21), the second light-emitting structure (22), and the third light-emitting structure (23), respectively, and the three second electrodes (51) are electrically isolated from each other.

10. The semiconductor structure according to claim 1, wherein: Among the first light-emitting structure (21), the second light-emitting structure (22) and the third light-emitting structure (23), the light-emitting structure with the largest light-emitting wavelength has the largest projection area on the carrier (10).

11. The semiconductor structure according to claim 1, wherein: The light-emitting unit (20) comprises a light-emitting layer (200) and a light conversion layer (201) that are stacked, and the light conversion layer (201) is located between the light-emitting layer (200) and the lens (30); The light conversion layers (201) of the first light-emitting structure (21), the second light-emitting structure (22), and the third light-emitting structure (23) are different, so that the light-emitting wavelengths of the first light-emitting structure (21), the second light-emitting structure (22), and the third light-emitting structure (23) are different.

12. A method for preparing a semiconductor structure, characterized in that: include: A plurality of light-emitting units (20) are formed, wherein the light-emitting units (20) include a first light-emitting structure (21), a second light-emitting structure (22), and a third light-emitting structure (23) which are arranged at intervals and have different light-emitting wavelengths, wherein the second light-emitting structure (22) surrounds the first light-emitting structure (21), and the third light-emitting structure (23) surrounds the second light-emitting structure (22); Bonding the light-emitting unit (20) to the carrier (10); as well as A plurality of lenses (30) are formed on a side of the light-emitting unit (20) facing away from the carrier (10), the plurality of lenses (30) respectively corresponding to the plurality of light-emitting units (20), and the lenses (30) converge light emitted by the light-emitting units (20).

13. The method according to claim 12, characterized in that The forming of the plurality of light emitting units (20) comprises: providing a growth substrate (60); forming a first dielectric layer (71) covering the growth substrate (60), wherein the first dielectric layer (71) includes a first groove (81) exposing the growth substrate (60); Epitaxially fabricating a first light-emitting structure (21) in the first groove (81); forming a second dielectric layer (72) covering the first light-emitting structure (21) and the first dielectric layer (71); Etching the second dielectric layer (72) to form a second groove (82) surrounding the first light-emitting structure (21) and exposing the growth substrate (60); Epitaxially fabricating a second light-emitting structure (22) in the second groove (82); forming a third dielectric layer (73) covering the second light-emitting structure (22) and the second dielectric layer (72); etching the third dielectric layer (73) to form a third groove (83) surrounding the second light-emitting structure (22) and exposing the growth substrate (60); and A third light-emitting structure (23) is epitaxially fabricated in the third groove (83).

14. The method according to claim 12, characterized in that The forming of the plurality of light emitting units (20) comprises: providing a growth substrate (60); forming a fourth dielectric layer covering the growth substrate (60); Etching the fourth dielectric layer to form at least one fourth groove (84), a plurality of fifth grooves (85), and a plurality of sixth grooves (86) exposing the growth substrate (60), wherein the plurality of fifth grooves (85) surround the fourth groove (84), and the plurality of sixth grooves (86) surround the plurality of fifth grooves (85), and the fourth groove (84), the fifth groove (85), and the sixth groove (86) have different projected areas on the growth substrate (60); The first light-emitting structure (21), the second light-emitting structure (22) and the third light-emitting structure (23) having different light-emitting wavelengths are produced by epitaxial growth at one time in the fourth groove (84), the fifth groove (85) and the sixth groove (86).

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