Semiconductor structure and method of manufacturing the same

Abstract

The present application provides a semiconductor structure and a method for manufacturing the same. The semiconductor structure includes a transparent substrate, an epitaxial structure and a distributed Bragg reflector structure. The epitaxial structure is disposed on one side of the transparent substrate, and the distributed Bragg reflector structure is disposed on the back side of the transparent substrate opposite to the epitaxial structure. Visible light can substantially sequentially penetrate the epitaxial structure, the transparent substrate and the distributed Bragg reflector structure, but other light other than the visible light can be substantially reflected by the distributed Bragg reflector structure back into the transparent substrate.

Description

Technical Field

[0001] This invention relates to a semiconductor structure and a method for manufacturing the same, and more particularly to a semiconductor structure and a method for manufacturing the same to improve optical alignment. Background Technology

[0002] Optical alignment calibration is a crucial step in semiconductor manufacturing, particularly in the photolithography process, to ensure precise alignment of patterns on a wafer for proper stacking of multilayer structures. This technology involves using an optical system to detect alignment marks and adjusting the position of the wafer or mask based on the location of these marks, thereby guaranteeing nanometer-level precision.

[0003] Optical alignment calibration techniques applied to transparent substrates (e.g., silicon carbide, gallium nitride, or other transparent materials) differ from traditional silicon-based processes. This is primarily because the physical properties of transparent substrates (such as optical transparency, refractive index, and thickness uniformity) present unique challenges to the design and implementation of optical alignment calibration systems. Specifically, existing conventional techniques place a metal mirror on one side of the transparent substrate to significantly improve the intensity and contrast of the alignment mark reflection signal.

[0004] However, using metal mirrors presents two main problems. First, metal mirrors have limited high-temperature resistance and cannot withstand the high temperatures encountered during the manufacturing process (e.g., potentially up to 800°C). Therefore, during high-temperature processes, metal mirrors may deform or degrade in performance, affecting the stability of the process results. Second, metal mirrors generate high reflectivity in the visible light region relative to the alignment marks, thus affecting alignment calibration in subsequent exposure lithography processes, leading to ineffective alignment. Summary of the Invention

[0005] The main objective of this invention is to provide an innovative semiconductor structure and its manufacturing method, employing a dual-band Bragg mirror structure in a transparent substrate for optical alignment calibration during the manufacturing process. It provides high reflectivity for light in the 436 nm and 940 nm wavelength bands and high average transmittance for visible light in the 500–750 nm range. Applied to edge alignment on transparent substrates, it enhances the calibration of wafer alignment marks in photolithography and improves the accuracy and intensity of exposure in photolithography. Furthermore, the dual-band Bragg mirror structure of this invention exhibits high-temperature resistance, capable of withstanding process temperatures exceeding 800°C, ensuring the stability of the mirror structure in subsequent high-temperature thin-film deposition processes, thereby improving the accuracy and efficiency of process alignment calibration.

[0006] To achieve the above objectives, the present invention provides a semiconductor structure comprising a transparent substrate, an epitaxial structure, and a distributed Bragg mirror structure. The epitaxial structure is disposed on one side of the transparent substrate, and the distributed Bragg mirror structure is disposed on the back side of the transparent substrate opposite to the epitaxial structure. Visible light can substantially and sequentially penetrate the epitaxial structure, the transparent substrate, and the distributed Bragg mirror structure, but other light rays besides visible light can be substantially reflected back into the transparent substrate by the distributed Bragg mirror structure.

[0007] In one embodiment of the semiconductor structure of the present invention, the distributed Bragg reflector structure includes a first symmetrical film stack having multiple pairs of alternating stacked first oxide films and second oxide films, wherein a refractive index of the first oxide film is greater than a refractive index of the second oxide film.

[0008] In a semiconductor structure according to an embodiment of the present invention, the thicknesses of each first oxide film and each second oxide film in the first symmetrical film stack have a first front-to-back symmetry relationship.

[0009] In one embodiment of the semiconductor structure of the present invention, the distributed Bragg reflector structure further includes a second symmetric film stack having multiple pairs of first oxide films and second oxide films stacked alternately, and the thickness of each first oxide film and each second oxide film in the second symmetric film stack is greater than the thickness of each first oxide film and each second oxide film in the first symmetric film stack.

[0010] In a semiconductor structure according to an embodiment of the present invention, the thicknesses of each first oxide film and each second oxide film in the second symmetrical film stack have a second front-to-back symmetry relationship.

[0011] In a semiconductor structure according to an embodiment of the present invention, the refractive index of the first oxide thin film and the second oxide thin film ranges from 1.4 to 3.0.

[0012] In a semiconductor structure according to an embodiment of the present invention, the first oxide film and the second oxide film are two of silicon dioxide (SiO2), titanium dioxide (TiO2), tantalum pentoxide (Ta2O5), niobium pentoxide (Nb2O5), aluminum oxide (Al2O3), and zirconium dioxide (ZrO2).

[0013] In a semiconductor structure according to an embodiment of the present invention, the thickness range of each first oxide film and each second oxide film in the first symmetrical film stack is 20 to 60 nanometers (nm).

[0014] In a semiconductor structure according to an embodiment of the present invention, the thickness range of each first oxide film and each second oxide film in the second symmetrical film stack is 50 to 220 nanometers (nm).

[0015] In one embodiment of the semiconductor structure of the present invention, the total thickness of the distributed Bragg reflector structure ranges from 800 nanometers (nm) to 3 micrometers (μm).

[0016] In a semiconductor structure according to an embodiment of the present invention, the other light includes a dual-band light of 436 nanometers (nm) and 940 nanometers (nm).

[0017] To achieve the above objectives, the present invention provides a semiconductor structure comprising a transparent substrate and a distributed Bragg reflector structure. The distributed Bragg reflector structure is disposed on a back side of the transparent substrate. The distributed Bragg reflector structure includes a first symmetrical film stack and a second symmetrical film stack. The first symmetrical film stack has multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films, and the second symmetrical film stack has multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films. The thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack is greater than the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack. Visible light can substantially and sequentially penetrate the epitaxial structure and the distributed Bragg reflector structure, but other light rays besides visible light can be substantially reflected back into the transparent substrate by the distributed Bragg reflector structure.

[0018] In another embodiment of the semiconductor structure of the present invention, the thicknesses of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack have a first front-to-back symmetry relationship, and the thicknesses of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack have a second front-to-back symmetry relationship.

[0019] In another embodiment of the semiconductor structure of the present invention, the refractive index range of the low refractive index oxide film and the high refractive index oxide film is 1.4 to 3.0.

[0020] In another embodiment of the semiconductor structure of the present invention, the low-refractive-index oxide film and the high-refractive-index oxide film are two of silicon dioxide (SiO2), titanium dioxide (TiO2), tantalum pentoxide (Ta2O5), niobium pentoxide (Nb2O5), aluminum oxide (Al2O3), and zirconium dioxide (ZrO2).

[0021] In another embodiment of the semiconductor structure of the present invention, the thickness range of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack is 20 to 60 nanometers (nm).

[0022] In another embodiment of the semiconductor structure of the present invention, the thickness range of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack is 50 to 220 nanometers (nm).

[0023] In another embodiment of the semiconductor structure of the present invention, the total thickness of the distributed Bragg reflector structure ranges from 800 nanometers (nm) to 3 micrometers (μm).

[0024] In another embodiment of the semiconductor structure of the present invention, the other light includes a dual-band light of 436 nanometers (nm) and 940 nanometers (nm).

[0025] To achieve the above objectives, the present invention provides a method for manufacturing a semiconductor structure, comprising the following steps: First, providing a transparent substrate. Second, forming a distributed Bragg reflector structure disposed on a back side of the transparent substrate. The distributed Bragg reflector structure comprises: a first symmetrical film stack having multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films; and a second symmetrical film stack having multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films, wherein the thickness of each oxide film in the second symmetrical film stack is greater than the thickness of each oxide film in the first symmetrical film stack, such that visible light can substantially sequentially penetrate the transparent substrate and the distributed Bragg reflector structure, but other light rays besides visible light can be substantially reflected back into the transparent substrate by the distributed Bragg reflector structure.

[0026] Other objects of the present invention, as well as the technical means and implementation methods of the present invention, will be understood by those skilled in the art upon referring to the accompanying drawings and the embodiments described below. Attached Figure Description

[0027] Figure 1 This diagram shows a semiconductor structure according to an embodiment of the present invention;

[0028] Figure 2 This diagram illustrates the front-to-back symmetry relationship of two sets of symmetrical film stacks in a distributed Bragg reflector structure according to an embodiment of the present invention.

[0029] Figure 3 A schematic diagram showing the spectrum of a dual-band distributed Bragg reflector design according to an embodiment of the present invention; and

[0030] Figure 4 This diagram illustrates the process steps of a semiconductor structure according to an embodiment of the present invention.

[0031] Explanation of reference numerals in the attached figures

[0032] 1. Transparent substrate

[0033] 10 Distributed Bragg mirror structure

[0034] 20. Epitaxial Structure

[0035] 30 photoresist layers

[0036] 32 Alignment Markers

[0037] 100 Semiconductor Structure

[0038] L1 First oxide film

[0039] L2 Second oxide film

[0040] L3 Third oxide film

[0041] L4 Fourth oxide film

[0042] L6 sixth oxide film

[0043] L8 8th oxide film

[0044] L9 9th oxide film

[0045] L 10 10th oxide film

[0046] L 11 11th oxide film

[0047] L 12 12th oxide film

[0048] L 13 13th oxide film

[0049] L 14 14th layer oxide film

[0050] L 15 15th layer oxide film

[0051] L 17 17th layer oxide film

[0052] L 19 19th layer oxide film

[0053] L 20 20th oxide film

[0054] L 21 21st layer oxide film

[0055] L 22 22nd layer oxide film

[0056] S1 First Symmetric Membrane Stack

[0057] S2 Second Symmetric Membrane Stack. Detailed Implementation

[0058] The following embodiments will explain the content of this invention. These embodiments are not intended to limit the implementation of this invention to any specific environment, application, or special method described in the embodiments. Therefore, the descriptions of the embodiments are merely illustrative of the invention and not intended to limit it. It should be noted that in the following embodiments and accompanying drawings, elements not directly related to this invention have been omitted and are not shown, and the dimensional relationships between the elements in the drawings are for ease of understanding only and are not intended to limit the actual scale.

[0059] Please see Figure 1 This diagram illustrates a semiconductor structure according to an embodiment of the present invention. In this embodiment, the semiconductor structure 100 includes a transparent substrate 1, a distributed Bragg reflector (DBR) structure 10, and an epitaxial structure 20. The transparent substrate 1 can be, for example, but not limited to, a sapphire substrate, a silicon carbide substrate, or a gallium nitride substrate. To overcome the various problems encountered in conventional techniques regarding optical alignment calibration of transparent substrates, the present invention specifically forms a distributed Bragg reflector structure 10 on an exposed back side of the transparent substrate 1 before performing the device epitaxial process. This structure serves as the basis for optical alignment calibration during the subsequent patterning process of the epitaxial structure on the transparent substrate, as detailed below.

[0060] Next, an epitaxial process is performed on the transparent substrate 1 to form an epitaxial structure 20. Then, a photoresist layer 30 and an alignment mark 32 on the photoresist layer 30 are formed on the epitaxial structure 20. The photoresist layer 30 is the so-called zero layer, used to establish the reference coordinate system for the entire wafer and to set the alignment mark 32. The alignment mark is shown in a top-down magnification. Figure 1 And displayed in Figure 1 The magnified area is indicated by the scribed line. It should be noted that the aforementioned epitaxial structure 20 can grow different epitaxial films according to the design requirements of the device in actual applications, thereby forming different types of devices, such as Schottky diodes or high electron mobility transistors (HEMTs) applied to third-generation semiconductor transparent substrates, but not limited thereto. Since this invention does not focus on the internal epitaxial structure design of the device, the epitaxial structure portion is only represented by an epitaxial structure 20, and detailed technical details of the device structure are omitted hereafter. Those skilled in the art can easily apply the optical alignment calibration technology of this invention to the epitaxial processes of various devices to obtain high-precision and stable alignment calibration.

[0061] Please continue reading. Figure 1The following will describe in detail the distributed Bragg reflector structure 10 disposed on the back side of the transparent substrate 1 and opposite to the epitaxial structure 20 of the present invention. As shown in the figure, in a preferred embodiment, the distributed Bragg reflector structure 10 of the present invention is a dual-band distributed Bragg reflector, which allows visible light with a wavelength range of 500-750 nanometers (nm) to substantially sequentially penetrate the epitaxial structure 20, the transparent substrate 1, and the distributed Bragg reflector structure 10. On the other hand, other light rays other than visible light, such as, but not limited to, ultraviolet light with a wavelength of 436 nanometers (nm) and / or infrared light with a wavelength of 940 nanometers (nm), can be substantially reflected back into the transparent substrate 1 by the distributed Bragg reflector structure 10.

[0062] In detail, in a preferred embodiment, the distributed Bragg reflector structure 10 of the present invention has two sets of symmetrical optical thin film stacked structures, including a first symmetrical film stack S1 and a second symmetrical film stack S2. The first symmetrical film stack S1 is composed of multiple pairs of alternately stacked optical dielectric thin films, each pair having two types of optical dielectric thin films, including a first oxide thin film and a second oxide thin film. Similarly, the second symmetrical film stack S2 is also composed of multiple pairs of alternately stacked first oxide thin films and second oxide thin films. Specifically, the first oxide thin film is a high refractive index oxide thin film, and the second oxide thin film is a low refractive index oxide thin film. For example, the first oxide thin film can be, but is not limited to, titanium dioxide (TiO2) with a refractive index of approximately 2.2 to 2.7. The second oxide thin film can be, but is not limited to, silicon dioxide (SiO2) with a refractive index of approximately 1.4 to 1.5. In essence, the first oxide film and the second oxide film can be selected from oxide dielectric materials with a refractive index range of 1.4 to 3.0. For example, two high- and low-refractive-index oxide dielectric materials can be selected from silicon dioxide (SiO2), titanium dioxide (TiO2), tantalum pentoxide (Ta2O5), niobium pentoxide (Nb2O5), aluminum oxide (Al2O3), zirconium dioxide (ZrO2) and other oxide dielectric materials as two oxide films that are stacked alternately.

[0063] Taking titanium dioxide (TiO2) as the first oxide film and silicon dioxide (SiO2) as the second oxide film as an example, the distributed Bragg reflector structure 10 with dual-band characteristics of the present invention is composed of a first symmetrical film stack S1 and a second symmetrical film stack S2. Each symmetrical film stack has 11 layers of alternating high and low refractive index oxide films, but this is not a limitation. For example, the distributed Bragg reflector structure 10 of the present invention can be composed of two or more symmetrical film stacks, and the number of logarithms or layers of two alternating optical films in each symmetrical film stack can be increased or decreased according to the actual application.

[0064] Taking the distributed Bragg reflector structure 10 as an example, which consists of two sets of film stacks, a first symmetric film stack S1 and a second symmetric film stack S2, and each set of film stacks has 11 oxide thin films, as shown in Table 1 below. Figure 1 As shown, the first symmetrical film stack S1 includes a first oxide film L1, a second oxide film L2, a third oxide film L3... an eleventh oxide film L... 11 The second symmetric film stack S2 includes a 12th oxide film L. 12 …20th oxide film L 20 , 21st oxide film L 21 , 22nd oxide film L 22 Furthermore, each layer of the oxide film is composed of alternating stacks of titanium dioxide (TiO2) and silicon dioxide (SiO2). Since both of these oxide dielectric materials are high-temperature resistant materials, with titanium dioxide (TiO2) having a melting point of approximately 1843°C and silicon dioxide (SiO2) having a melting point of approximately 1713°C, the distributed Bragg reflector structure 10 of this invention is provided with the ability to withstand process temperatures exceeding 800°C.

[0065]

[0066] Table 1

[0067] Specifically, to increase the reflection efficiency of the reflector, the present invention arranges the film layers in the first symmetrical film stack S1 and the second symmetrical film stack S2 of the distributed Bragg reflector structure 10 to have a first front-to-back symmetry relationship and a second front-to-back symmetry relationship, respectively. Please refer to [link to relevant documentation]. Figure 2 This diagram illustrates two front-to-back symmetry relationships in the two sets of symmetrical film stacks of the distributed Bragg reflector structure in the semiconductor structure of the present invention. Specifically, taking the aforementioned embodiment as an example, the first front-to-back symmetry relationship refers to a situation where, with the central layer L6 of the first symmetrical film stack S1 as the center, the thickness and oxide film material of all layers before and after this central layer are the same. Please refer to both documents together. Figure 1 , Figure 2 As shown in Table 1, the thicknesses of the 5th oxide film L5 and the 7th oxide film L7, located before and after the central layer L6, are the same, approximately 49.3 nanometers (nm). Both oxide film materials are titanium dioxide (TiO2). Furthermore, in the first symmetrical film stack S1, the 1st oxide film L1 and the 11th oxide film L... (The text abruptly ends here, so the translation stops as well.) 11 Both have the same thickness, approximately 24.6 nanometers (nm), and both are made of titanium dioxide (TiO2). Similarly, the second front-to-back symmetry relationship refers to the central layer L of the second symmetry film stack S2. 17 Centered on this central layer, the thickness of all layers before and after it is the same as that of the oxide film material. For example, located in the central layer L... 17 The 16th oxide film L at the front and back16 and the 18th oxide film L 18 Both have the same thickness, approximately 205.2 nanometers (nm), and both are made of silicon dioxide (SiO2). Furthermore, in the second symmetric film stack S2, the central layer L... 17 The 12th oxide film layer L at the very front and the very back 12 and the 22nd oxide film L 22 Both have the same thickness, approximately 102.6 nanometers (nm), and both are made of silicon dioxide (SiO2).

[0068] In the specific embodiments described above, the thickness of each first oxide film and each second oxide film in the first symmetrical film stack S1 ranges from 20 to 60 nanometers (nm). On the other hand, the thickness of each first oxide film and each second oxide film in the second symmetrical film stack S2 ranges from 50 to 220 nanometers (nm). Thus, the total thickness of the distributed Bragg reflector structure 10 of the present invention, composed of the two sets of symmetrical film stacks, ranges from 800 nanometers (nm) to 3 micrometers (μm).

[0069] Furthermore, to achieve a dual-band reflection effect, preferably, the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack S2 (totaling 11 layers) is greater than the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack S1 (also totaling 11 layers). Under this film structure, the designed spectrum achievable by the dual-band Bragg reflector structure of the present invention has the following characteristics: the optical reflection efficiency substantially achievable by the first symmetrical film stack S1 reaches a reflectance greater than 80% in the 436 nm band, with a half-width at half-maximum (HWHM) of 130–150 nm, and a suitable wavelength range for ultraviolet light of 370–500 nm. On the other hand, the optical reflection efficiency substantially achievable by the second symmetrical film stack S2 reaches a reflectance (R%) greater than 80% in the 940 nm band, with a HWHM of 200–400 nm, and a suitable wavelength range for infrared light of 750–1100 nm. Furthermore, it achieves an average transmittance (T%) greater than 80% in the visible light region, and its applicable wavelength range for visible light is 500–750 nanometers (nm). Figure 3 As shown.

[0070] As described above, the dual-band Bragg reflector structure of this invention achieves a high reflectivity of over 80% in the 436 nm and 940 nm wavelengths outside the visible light region, and provides a high average transmittance of over 80% in the 500–750 nm visible light region. This allows for the application of infrared light in the 940 nm wavelength band for edge alignment of the transparent substrate, overcoming the limitation that visible light cannot be used for edge alignment of transparent substrates. Furthermore, in the 436 nm wavelength band, it can be applied to the G-line exposure wavelength in subsequent photolithography processes to enhance the accuracy and intensity of exposure. On the other hand, in the visible light band, the dual-band Bragg reflector structure of this invention allows visible light to penetrate the transparent substrate and the reflector structure itself without causing reflection that would interfere with the calibration signal of the alignment marks, thereby enhancing the calibration signal of the alignment marks 32 on the surface of the wafer photoresist layer 30. Furthermore, the material of this reflective film is an oxide dielectric material, thus possessing high-temperature resistance and withstanding process temperatures up to 800°C. This ensures the stability of the reflective structure during subsequent high-temperature thin-film deposition processes, thereby improving process accuracy and efficiency. This heat resistance is substantially different from reflectives made using metals such as silver and aluminum, as these metals have low melting points and are unsuitable for subsequent high-temperature processes. As a result, this invention possesses high-temperature resistance and dual-band high reflectivity, achieving superior multi-band optical alignment and calibration effects.

[0071] Please see Figure 4 This diagram illustrates the process steps of the semiconductor structure of the present invention. First, in step S01, a transparent substrate is provided. Second, in step S02, a distributed Bragg reflector structure is formed and disposed on the back side of the transparent substrate. The distributed Bragg reflector structure includes: a first symmetrical film stack having multiple pairs of alternating low-refractive-index oxide films and high-refractive-index oxide films; and a second symmetrical film stack having multiple pairs of alternating low-refractive-index oxide films and high-refractive-index oxide films. The thickness of each oxide film in the second symmetrical film stack is greater than the thickness of each oxide film in the first symmetrical film stack, such that visible light can substantially and sequentially penetrate the transparent substrate and the distributed Bragg reflector structure, but other light rays besides visible light can be substantially reflected back into the transparent substrate by the distributed Bragg reflector structure. The descriptions of the relevant components are as described above and will not be repeated here.

[0072] The above embodiments are merely illustrative of implementation schemes of the present invention and to explain the technical features of the present invention, and are not intended to limit the scope of protection of the present invention. Any changes or equivalent arrangements that can be easily made by those skilled in the art are within the scope of the present invention, and the scope of protection of the present invention should be determined by the claims.

Claims

1. A semiconductor structure comprising: A transparent substrate; An epitaxial structure is disposed on one side of the transparent substrate; and A distributed Bragg reflector structure is disposed on the back side of the transparent substrate opposite to the epitaxial structure. in, Visible light can substantially pass through the epitaxial structure, the transparent substrate, and the distributed Bragg mirror structure in a substantial sequence, but other light rays besides the visible light can be substantially reflected back into the transparent substrate by the distributed Bragg mirror structure.

2. The semiconductor structure of claim 1, wherein the distributed Bragg reflector structure comprises a first symmetrical film stack having multiple pairs of alternating stacked first oxide films and second oxide films, wherein a refractive index of the first oxide film is greater than a refractive index of the second oxide film.

3. The semiconductor structure as claimed in claim 2, wherein the thicknesses of each of the first oxide films and each of the second oxide films in the first symmetrical film stack have a first front-to-back symmetry relationship.

4. The semiconductor structure of claim 2, wherein the distributed Bragg reflector structure further comprises a second symmetric film stack having multiple pairs of alternating stacked first oxide films and second oxide films, and the thickness of each of the first oxide films and each of the second oxide films in the second symmetric film stack is greater than the thickness of each of the first oxide films and each of the second oxide films in the first symmetric film stack.

5. The semiconductor structure of claim 4, wherein the thickness of each of the first oxide films and each of the second oxide films in the second symmetrical film stack has a second front-to-back symmetry relationship.

6. The semiconductor structure of claim 2, wherein the refractive index of the first oxide film and the second oxide film is in the range of 1.4 to 3.

0.

7. The semiconductor structure as claimed in claim 2, wherein the first oxide film and the second oxide film are two of silicon dioxide, titanium dioxide, tantalum pentoxide, niobium pentoxide, aluminum oxide, and zirconium dioxide.

8. The semiconductor structure of claim 2, wherein the thickness of each of the first oxide film and each of the second oxide film in the first symmetrical film stack is in the range of 20 to 60 nanometers.

9. The semiconductor structure of claim 4, wherein the thickness of each of the first oxide film and each of the second oxide film in the second symmetric film stack ranges from 50 to 220 nanometers.

10. The semiconductor structure of claim 1, wherein the total thickness of the distributed Bragg mirror structure ranges from 800 nanometers to 3 micrometers.

11. The semiconductor structure of claim 1, wherein the other light comprises a dual-band light of 436 nm and 940 nm.

12. A semiconductor structure comprising: A transparent substrate; and A distributed Bragg reflector structure, disposed on one back side of the transparent substrate, includes: A first symmetrical film stack is disposed on a back side of the transparent substrate, the first symmetrical film stack having multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films; and A second symmetrical film stack has multiple pairs of alternating low-refractive-index oxide films and high-refractive-index oxide films, wherein the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack is greater than the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack. in, Visible light can substantially pass through the transparent substrate and the distributed Bragg mirror structure in sequence, but other light rays besides the visible light can be substantially reflected back into the transparent substrate by the distributed Bragg mirror structure.

13. The semiconductor structure of claim 12, wherein the thicknesses of each of the low-refractive-index oxide films and each of the high-refractive-index oxide films in the first symmetrical film stack have a first front-to-back symmetry relationship, and the thicknesses of each of the low-refractive-index oxide films and each of the high-refractive-index oxide films in the second symmetrical film stack have a second front-to-back symmetry relationship.

14. The semiconductor structure of claim 12, wherein the refractive index of the low-refractive-index oxide film and the high-refractive-index oxide film is in the range of 1.4 to 3.

0.

15. The semiconductor structure of claim 12, wherein the low-refractive-index oxide film and the high-refractive-index oxide film are two of silicon dioxide, titanium dioxide, tantalum pentoxide, niobium pentoxide, aluminum oxide, and zirconium dioxide.

16. The semiconductor structure of claim 12, wherein the thickness of each of the low-refractive-index oxide films and each of the high-refractive-index oxide films in the first symmetrical film stack is in the range of 20 to 60 nanometers.

17. The semiconductor structure of claim 12, wherein the thickness of each of the low-refractive-index oxide films and each of the high-refractive-index oxide films in the second symmetrical film stack ranges from 50 to 220 nanometers.

18. The semiconductor structure of claim 12, wherein the total thickness of the distributed Bragg mirror structure ranges from 800 nanometers to 3 micrometers.

19. The semiconductor structure of claim 12, wherein the other light comprises a dual-band light of 436 nm and 940 nm.

20. A method for manufacturing a semiconductor structure, comprising: Provide a transparent substrate; and A distributed Bragg reflector structure is formed and disposed on a back side of the transparent substrate. The distributed Bragg reflector structure includes: A first symmetrical film stack is disposed on a back side of the transparent substrate, having multiple pairs of alternating stacked low-refractive-index oxide films and high-refractive-index oxide films; and A second symmetrical film stack has multiple pairs of alternating low-refractive-index oxide films and high-refractive-index oxide films, wherein the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the second symmetrical film stack is greater than the thickness of each low-refractive-index oxide film and each high-refractive-index oxide film in the first symmetrical film stack. in, Visible light can substantially pass through the transparent substrate and the distributed Bragg mirror structure in sequence, but other light rays besides the visible light can be substantially reflected back into the transparent substrate by the distributed Bragg mirror structure.

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