Ambient light sensor with ultraviolet light sensing function

Abstract

The invention provides an ambient light sensor with an ultraviolet light sensing function. The ambient light sensor is used for receiving external light for sensing. The ambient light sensor comprises a visible light sensing chip and a wavelength conversion layer. The visible light sensing chip is used for sensing light corresponding to the visible light response wave band, and the visible light sensing chip comprises a light receiving surface. The wavelength conversion layer is used for converting light corresponding to a specific ultraviolet light wave band in external light into light corresponding to a visible light response wave band, and the wavelength conversion layer covers at least one part of the light receiving surface.

Description

Technical Field

[0001] The invention relates to an ambient light sensor, in particular to an ambient light sensor capable of providing an ultraviolet light sensing function. Background Art

[0002] Ambient light sensors (ALS) can be applied to electronic devices to sense changes in ambient light and adjust or switch the functions of the electronic device accordingly. For example, when an ambient light sensor is applied to a smartphone or a device with a similar display screen, the brightness of the display screen can be automatically adjusted according to the sensing result of the ambient light sensor.

[0003] Ambient light sensors can be roughly divided into visible light sensors, infrared light sensors, and ultraviolet light sensors depending on the absorption layer materials used. When there is a need to sense different light, more than two of the above light sensors must be used at the same time, which is inconvenient to use. Furthermore, the existing ambient light sensors using silicon as the absorption layer material can support the sensing of the UV-A ultraviolet light band, but the sensing response of the ambient light sensor to the ultraviolet light band is low, and the band of 400nm to 1000nm in the light will also become noise, thereby affecting the existing ultraviolet light sensor's ability to sense ultraviolet light; in addition, the application of the ambient light sensor is also limited to UV-A ultraviolet ultraviolet sensing. Moreover, although the existing ambient light sensors using silicon carbide as the absorption layer material can support the sensing of a wider range of ultraviolet light bands, the ambient light sensors cannot detect visible light bands.

[0004] Therefore, how to design an ambient light sensor that can improve the above-mentioned problems is indeed a topic worth studying. Summary of the invention

[0005] The object of the present invention is to provide an ambient light sensor which uses a visible light sensing chip and can provide an ultraviolet light sensing function.

[0006] Another object of the present invention is to provide an ambient light sensor that can filter and sense a specified ultraviolet light band.

[0007] Another object of the present invention is to provide an ambient light sensor that combines visible light sensing and ultraviolet light sensing functions.

[0008] To achieve the above-mentioned purpose, the ambient light sensor with ultraviolet light sensing function of the present invention comprises a visible light sensing chip and a wavelength conversion layer. The visible light sensing chip is used to sense light corresponding to the visible light response band, and the visible light sensing chip comprises a light receiving surface. The wavelength conversion layer is used to convert light corresponding to a specific ultraviolet light band in the external light into light corresponding to the visible light response band, and the wavelength conversion layer covers at least a portion of the light receiving surface.

[0009] In one embodiment of the present invention, the wavelength conversion layer covers the entire light receiving surface.

[0010] In one embodiment of the present invention, the ambient light sensor with ultraviolet light sensing function further includes a bandpass filter for filtering light corresponding to a specific ultraviolet light band in the external light, and the bandpass filter is formed on the wavelength conversion layer.

[0011] In one embodiment of the present invention, the band-pass filter membrane is a multilayer membrane structure formed by alternately stacking two different materials, and the band-pass filter membrane includes a combination of two different dielectric materials or a combination of a metal and a dielectric material.

[0012] In one embodiment of the present invention, the specific ultraviolet light wavelength band is selected from at least one of the following wavelength band groups: 315 nm to 400 nm, 280 nm to 315 nm, and 100 nm to 280 nm.

[0013] In one embodiment of the present invention, the wavelength conversion layer is made of phosphor material.

[0014] In one embodiment of the present invention, the visible light sensor chip forms a plurality of channel regions, and the wavelength conversion layer at least covers a light receiving surface corresponding to at least one of the plurality of channel regions.

[0015] In one embodiment of the present invention, a recessed structure is formed between two adjacent channel regions of the plurality of channel regions.

[0016] In one embodiment of the present invention, the visible light response band is 460nm to 660nm.

[0017] In one embodiment of the present invention, the visible light sensor chip includes a semiconductor stack structure, and the semiconductor stack structure includes an InGaAlP material layer.

[0018] In one embodiment of the present invention, the visible light sensing chip further includes a substrate, a first electrode layer and a second electrode layer, the semiconductor stacking structure and the first electrode layer are respectively located on two opposite sides of the substrate, the side of the semiconductor stacking structure facing away from the substrate forms a light receiving surface, and the second electrode layer is located on the light receiving surface and exposed to the wavelength conversion layer.

[0019] Accordingly, the ambient light sensor with ultraviolet light sensing function of the present invention can provide the sensing function of the ultraviolet light band through the arrangement of the wavelength conversion layer, so that the visible light sensing chip can also provide the sensing function of the ultraviolet light band, and improve the response intensity to the ultraviolet light band. Furthermore, the ambient light sensor with ultraviolet light sensing function of the present invention can also provide the sensing functions of ultraviolet light and visible light at the same time, which can not only reduce the volume of the ambient light sensor but also reduce the manufacturing cost compared with the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 FIG. 4 is a schematic diagram of a first embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention.

[0021] Figure 2 FIG. 4 is a schematic diagram of a second embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention.

[0022] Figure 3 FIG. 4 is a schematic diagram of a third embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention.

[0023] Figure 4 FIG. 4 is a schematic diagram of a fourth embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention.

[0024] Figure 5 FIG. 5 is a schematic diagram of a fifth embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention.

[0025] Description of reference numerals:

[0026] 1, 1a, 1b, 1c, 1d Ambient light sensor with UV sensing function

[0027] 10 Visible light sensing chip

[0028] 11. Substrate

[0029] 12 Semiconductor stacking structure

[0030] 121 GaAs material layer

[0031] 122 Indium aluminum phosphide material layer

[0032] 123 InGaAlP material layer

[0033] 124 Indium aluminum phosphide material layer

[0034] 125 Gallium Phosphide Material Layer

[0035] 13. First electrode layer

[0036] 14. Second electrode layer

[0037] 141 First Electrode

[0038] 142 Second Electrode Section

[0039] 15 Concave structure

[0040] 20 Wavelength conversion layer

[0041] 30 Bandpass filter

[0042] 40 Circuit Board

[0043] 50 Package Structure

[0044] 60 Wire

[0045] 70 Cover

[0046] 80 Retaining Wall

[0047] A Light receiving surface

[0048] C1 First channel area

[0049] C2 Second channel area

[0050] L External light. DETAILED DESCRIPTION

[0051] Since the various aspects and embodiments are only exemplary and non-limiting, after reading this specification, ordinary technicians may also come up with other aspects and embodiments without departing from the scope of the present invention. According to the following detailed description and claims, the features and advantages of the embodiments will be more prominent.

[0052] In this document, "a" or "an" is used to describe the elements and components described herein. This is only for convenience of description and to provide a general meaning to the scope of the present invention. Therefore, unless it is obvious that it is otherwise intended, such description should be understood to include one or at least one, and the singular also includes the plural.

[0053] In this document, the terms "first" or "second" and the like ordinal numbers are mainly used to distinguish or refer to the same or similar elements or structures, and do not necessarily imply the order of these elements or structures in space or time. It should be understood that in some cases or configurations, the ordinal numbers can be used interchangeably without affecting the implementation of the present invention.

[0054] In this document, the terms "including", "having" or any other similar terms are intended to cover a non-exclusive inclusion. For example, an element or structure containing multiple elements is not limited to the elements listed herein, but may include other elements that are not explicitly listed but are generally inherent to the element or structure.

[0055] The ambient light sensor with ultraviolet light sensing function of the present invention is used to receive external light for sensing, and the external light may at least include general visible light and ultraviolet light, or even infrared light. Figure 1 FIG. 1 is a schematic diagram of a first embodiment of an ambient light sensor with ultraviolet light sensing function according to the present invention. Figure 1As shown, in this embodiment, the ambient light sensor 1 with ultraviolet light sensing function of the present invention includes a visible light sensing chip 10 and a wavelength conversion layer 20 , and the wavelength conversion layer 20 is formed on the visible light sensing chip 10 .

[0056] The visible light sensing chip 10 is used to sense light corresponding to the visible light response band. For example, in the present invention, the visible light response band that the visible light sensing chip 10 can sense is approximately 460nm to 660nm, and its wavelength response peak is approximately 560nm to 570nm, but the present invention is not limited thereto. The visible light sensing chip 10 includes a light receiving surface A, and external light L can enter the visible light sensing chip 10 through the light receiving surface A for sensing.

[0057] The visible light sensing chip 10 includes a substrate 11, a semiconductor stacking structure 12, a first electrode layer 13 and a second electrode layer 14. The substrate 11 is mainly used as a basic structural component for carrying and / or setting the aforementioned related structural components of the visible light sensing chip 10. In the present invention, the substrate 11 can adopt a gallium arsenide (GaAs) substrate, but the material of the substrate 11 can be changed according to different design requirements. The first electrode layer 13 is mainly used as one of the conduction paths of the current, and the first electrode layer 13 is located on one side of the substrate 11. In the present invention, the first electrode layer 13 can be made of a gold-containing alloy (Au-alloy) material, but the present invention is not limited to this.

[0058] The semiconductor stacking structure 12 is mainly used to absorb light corresponding to the visible light response band and convert it into a current signal, and the semiconductor stacking structure 12 is located on the other side of the substrate 11, that is, the semiconductor stacking structure 12 and the first electrode layer 13 are respectively located on two opposite sides of the substrate 11. The semiconductor stacking structure 12 can be made of III-V compound semiconductor materials. For example, in the present invention, the semiconductor stacking structure 12 includes gallium arsenide aluminum (AlGaAs) material layer 121, indium aluminum phosphide (AlInP) material layer 122, indium gallium aluminum phosphide (AlGaInP) material layer 123, indium aluminum phosphide material layer 124 and gallium phosphide (GaP) material layer 125 in sequence from the substrate 11 side. The indium gallium aluminum phosphide (AlGaInP) material layer 123 is used as the main light absorption layer. The semiconductor stacking structure 12 forms the light receiving surface A of the aforementioned visible light sensor chip 10 on the side facing away from the substrate 11 (i.e., the side of the gallium phosphide material layer 125 facing away from the indium aluminum phosphide material layer 124).

[0059] The second electrode layer 14 is mainly used as one of the conduction paths of the current, and the second electrode layer 14 is located on the light-receiving surface A. In the present invention, the second electrode layer 14 can also be made of a gold-containing alloy material, but the present invention is not limited thereto. The second electrode layer 14 is at least one bump structure convexly disposed on the light-receiving surface A, that is, the second electrode layer 14 only covers a partial area of ​​the light-receiving surface A, so that other areas of the light-receiving surface A can be incident with external light L.

[0060] In addition, in the present invention, the first electrode layer 13 is an N-type electrode, and the structural layers of the semiconductor stacking structure 12 adjacent to the first electrode layer 13 are made of N-type semiconductor materials; and the second electrode layer 14 is a P-type electrode, and the structural layers of the semiconductor stacking structure 12 adjacent to the second electrode layer 14 are made of P-type semiconductor materials, but the present invention is not limited thereto. For example, the aforementioned N-type and P-type electrodes or semiconductor materials can also be interchanged as required.

[0061] The wavelength conversion layer 20 is used to convert the light corresponding to the specific ultraviolet light band in the external light into the light corresponding to the visible light response band, so as to facilitate the sensing of the visible light sensor chip 10. The wavelength conversion layer 20 is located on the light receiving surface A of the visible light sensor chip 10, and the wavelength conversion layer 20 covers at least a portion of the light receiving surface A. In the present embodiment, the wavelength conversion layer 20 covers the entire light receiving surface A, and only the second electrode layer 14 protruding on the light receiving surface A is exposed to the wavelength conversion layer 20, but the present invention is not limited thereto. The specific ultraviolet light band that can be converted by the wavelength conversion layer 20 is selected from at least one of the following band groups: 315nm to 400nm, 280nm to 315nm, and 100nm to 280nm. Among them, 315nm to 400nm corresponds to the UV-A ultraviolet light band, 280nm to 315nm corresponds to the UV-B ultraviolet light band, and 100nm to 280nm corresponds to the UV-C ultraviolet light band. That is, the ultraviolet light band that the wavelength conversion layer 20 can convert can be a single band listed in the aforementioned group, or a combination of multiple bands. In the present invention, the wavelength conversion layer 20 is made of a material (such as phosphor) that has the function of converting ultraviolet light bands, and the specific ultraviolet light band that the wavelength conversion layer 20 can convert varies according to different phosphor materials.

[0062] Accordingly, when external light is incident on the ambient light sensor 1 with ultraviolet light sensing function of the present invention, the external light first reaches the wavelength conversion layer 20. At this time, the light corresponding to a specific ultraviolet light band (for example, corresponding to the UV-A ultraviolet light band) in the external light will be converted into light corresponding to the visible light response band (for example, corresponding to WD 550nm) through the wavelength conversion layer 20. Then, the light converted into the corresponding visible light response band will continue to pass through the light receiving surface A of the visible light sensing chip 10 and enter the semiconductor stacking structure 12 of the visible light sensing chip 10, so that the light is absorbed by the light absorption layer and corresponding sensing is performed. Finally, the ambient light sensor 1 with ultraviolet light sensing function of the present invention completes the sensing operation for ultraviolet light.

[0063] Please refer to Figure 2 FIG. 2 is a schematic diagram of a second embodiment of an ambient light sensor with ultraviolet light sensing function of the present invention. This embodiment is a variation of the first embodiment described above, and the difference lies in the arrangement of a filter membrane. Figure 2 As shown, in this embodiment, the ambient light sensor 1a with ultraviolet light sensing function of the present invention further includes a band pass filter 30. The band pass filter 30 is used to filter light corresponding to at least one specific ultraviolet light band in the external light to exclude light of other unnecessary bands. The band pass filter 30 is formed on the wavelength conversion layer 20. In this embodiment, the band pass filter 30 covers the entire wavelength conversion layer 20, and the second electrode layer 14 protruding from the light receiving surface A and exposed to the wavelength conversion layer 20 is also exposed to the band pass filter 30, but the present invention is not limited thereto. The specific ultraviolet light band that can be filtered by the aforementioned band pass filter 30 is selected from at least one of the following band groups: 315nm to 400nm (corresponding to UV-A ultraviolet light band), 280nm to 315nm (corresponding to UV-B ultraviolet light band) and 100nm to 280nm (corresponding to UV-C ultraviolet light band). That is, the ultraviolet wavelength band that can be filtered by the bandpass filter 30 can be a single wavelength band listed in the above group, or a combination of multiple wavelength bands. The bandpass filter 30 changes the corresponding specific ultraviolet wavelength band that can be filtered according to different materials and structural designs.

[0064] The band-pass filter 30 is generally a multilayer film structure formed by alternately stacking two different materials layer by layer, and the material of each thin film layer is different from the material of the adjacent thin film. For example, in terms of design, the band-pass filter 30 may adopt a combination of two dielectric materials with different n values, such as a silicon nitride (Si3N4) film and a silicon dioxide (SiO2) film to form an alternately stacked layer structure; or, the band-pass filter 30 may also adopt a combination of a metal and a dielectric material, such as an aluminum (Al) or silver (Ag) film and an aluminum oxide (Al2O3) or silicon dioxide film to form an alternately stacked layer structure, but the present invention is not limited thereto.

[0065] Accordingly, when external light is incident on the ambient light sensor 1a with ultraviolet light sensing function of the present invention, the external light L first reaches the bandpass filter 30. At this time, except for the light corresponding to a specific ultraviolet light band (for example, the UV-A ultraviolet light band) in the external light, which continues to pass through the bandpass filter 30 and reaches the wavelength conversion layer 20, the light of other bands will be filtered out by the bandpass filter 30; that is, the external light can only retain the light of a specific ultraviolet light band through the bandpass filter 30, thereby enhancing the sensing effect of ultraviolet light. Then, the light corresponding to the specific ultraviolet light band passing through the bandpass filter 30 will enter the wavelength conversion layer 20 and the visible light sensing chip 10 in sequence. Since the functional description of the wavelength conversion layer 20 and the visible light sensing chip 10 is the same as that of the first embodiment, it will not be repeated here.

[0066] Please refer to Figure 3 FIG. 1 is a schematic diagram of a third embodiment of an ambient light sensor with ultraviolet light sensing function of the present invention. This embodiment is a variation of the aforementioned second embodiment, and the difference lies in that the ultraviolet light and visible light sensing functions are combined through structural design. Figure 3 As shown, in this embodiment, the visible light sensing chip 10 of the ambient light sensor 1b with ultraviolet light sensing function of the present invention forms a plurality of channel regions, and a recessed structure is formed between two adjacent channel regions of the plurality of channel regions; the wavelength conversion layer 20 at least covers the position of the light receiving surface A corresponding to at least one of the plurality of channel regions. In addition, the second electrode layer forms independent electrode portions corresponding to each channel region.

[0067] For example, the aforementioned visible light sensor chip 10 may form adjacent first channel region C1 and second channel region C2, and the visible light sensor chip 10 further includes a recessed structure 15. The recessed structure 15 is located between the first channel region C1 and the second channel region C2, and the recessed structure 15 penetrates the semiconductor stacked structure 12 from the light receiving surface A of the visible light sensor chip 10 and extends to the position where the substrate 11 is located. In the present embodiment, the wavelength conversion layer 20 covers the local light receiving surface A corresponding to the first channel region C1, and a band pass filter 30 may be formed on the wavelength conversion layer 20, so that the first channel region C1 can provide ultraviolet light sensing function for external light; and the local light receiving surface A corresponding to the second channel region C2 is an exposed surface, so that the corresponding second channel region C2 can provide visible light sensing function for external light. The second electrode layer 14 forms a first electrode portion 141 protruding from the light receiving surface A corresponding to the first channel region C1, and the first electrode portion 141 is exposed to the wavelength conversion layer 20 and the band pass filter 30; the second electrode layer 14 forms a second electrode portion 142 protruding from the light receiving surface A corresponding to the second channel region C2. The first channel region C1 and the second channel region C2 are separated by the recessed structure 15 to avoid mutual interference between the sensing functions for ultraviolet light and visible light.

[0068] Please refer to Figure 4 FIG. 4 is a schematic diagram of a fourth embodiment of an ambient light sensor with ultraviolet light sensing function of the present invention. This embodiment is a variation of the first embodiment described above, and the difference lies in the arrangement of the wavelength conversion layer 20 and the packaging structure and circuit board combined with the visible light sensing chip. Figure 4As shown, in this embodiment, the visible light sensing chip 10 of the ambient light sensor 1c with ultraviolet light sensing function of the present invention is disposed on a circuit board 40. The first electrode layer 13 of the visible light sensing chip 10 is connected to the metal conductive layer of the circuit board 40 through silver glue, and the second electrode layer 14 of the visible light sensing chip 10 is connected to another metal conductive layer of the circuit board 40 through a wire 60 (such as a gold wire). Here, the circuit board 40 can be a printed circuit board. The packaging structure 50 is used to completely cover the visible light sensing chip 10 and the wire 60, and partially cover the circuit board 40, so as to complete the packaging of the ambient light sensor 1c with ultraviolet light sensing function of the present invention. Here, the packaging structure 50 can be transparent silicone or molded plastic (such as epoxy resin). In this embodiment, the wavelength conversion layer 20 is located on the packaging structure 50, and the area of ​​the wavelength conversion layer 20 is larger than the light receiving surface A of the visible light sensing chip 10, so that the wavelength conversion layer 20 can cover the entire light receiving surface A accordingly. In addition, a cover plate 70, such as a glass or plastic cover plate, can be selectively disposed on the wavelength conversion layer 20. Accordingly, the ambient light sensor 1c with ultraviolet light sensing function of the present invention increases the overall area of ​​the wavelength conversion layer 20, which not only ensures that external light passes through the wavelength conversion layer 20, but also allows the visible light sensing chip 10 to be combined with the packaging structure and the circuit board 40 to improve application convenience.

[0069] Please refer to Figure 5 FIG. 5 is a schematic diagram of a fifth embodiment of an ambient light sensor with ultraviolet light sensing function of the present invention. This embodiment is a variation of the fourth embodiment described above, and the difference lies in the addition of a retaining wall. Figure 5 As shown, in this embodiment, the ambient light sensor 1d with ultraviolet light sensing function of the present invention further has a retaining wall 80 disposed on the circuit board 40. The retaining wall 80 is located on the side of the packaging structure 50, and the retaining wall 80 can provide a support effect for the wavelength conversion layer 20 and / or the cover plate 70. The retaining wall 80 is mainly made of non-translucent epoxy resin, such as packaging black glue, so that the retaining wall 80 can block the light that passes through the wavelength conversion layer 20 from being scattered sideways, and prevent external light from entering from the side to affect the sensing result.

[0070] From the above embodiments, it can be seen that the ambient light sensor with ultraviolet light sensing function of the present invention can use a general visible light sensing chip to achieve the sensing function of the ultraviolet light band and improve the response intensity of the ultraviolet light band; furthermore, the ambient light sensor with ultraviolet light sensing function of the present invention can also use the same visible light sensing chip to provide the sensing functions of the ultraviolet light band and the visible light band at the same time. With the different materials and structures used in the wavelength conversion layer and / or the band pass filter, the ambient light sensor with ultraviolet light sensing function of the present invention can perform filtering and / or conversion operations for different ultraviolet light bands to meet different usage requirements.

[0071] The above embodiments are essentially only auxiliary explanations, and are not intended to limit the embodiments of the application subject or the application or use of the embodiments. In addition, although at least one exemplary embodiment has been proposed in the aforementioned embodiments, it should be understood that the present invention can still have a large number of changes. It should also be understood that the embodiments described herein are not intended to limit the scope, use or configuration of the requested application subject in any way. On the contrary, the aforementioned embodiments will provide a simple guide for those of ordinary skill in the art to implement one or more of the embodiments described. Furthermore, various changes can be made to the functions and arrangements of the components without departing from the scope defined by the claims, and the claims include known equivalents and all foreseeable equivalents at the time of the present application.

Claims

1. An ambient light sensor with ultraviolet light sensing function, used to receive external light for sensing, the ambient light sensor comprising: A visible light sensing chip, used to sense light corresponding to a visible light response band, and the visible light sensing chip includes a light receiving surface; as well as A wavelength conversion layer is used to convert the light corresponding to a specific ultraviolet light band in the external light into the light corresponding to the visible light response band, and the wavelength conversion layer covers at least a part of the light receiving surface.

2. The ambient light sensor with ultraviolet light sensing function as claimed in claim 1, further comprising a band-pass filter for filtering light corresponding to the specific ultraviolet light band in the external light, and the band-pass filter is formed on the wavelength conversion layer.

3. The ambient light sensor with ultraviolet light sensing function as described in claim 2, wherein the band-pass filter is a multilayer film structure formed by stacking two different materials alternately, and the band-pass filter includes a combination of two different dielectric materials or a combination of a metal and a dielectric material.

4. The ambient light sensor with ultraviolet light sensing function as claimed in claim 1, wherein the specific ultraviolet light band is selected from at least one of the following band groups: 315nm to 400nm, 280nm to 315nm and 100nm to 280nm. 5 . The ambient light sensor with ultraviolet light sensing function as claimed in claim 1 , wherein the wavelength conversion layer is made of fluorescent material. 6 . The ambient light sensor with ultraviolet light sensing function as claimed in claim 1 , wherein the visible light sensing chip forms a plurality of channel regions, and the wavelength conversion layer at least covers the light receiving surface corresponding to at least one of the plurality of channel regions. 7 . The ambient light sensor with ultraviolet light sensing function as claimed in claim 6 , wherein a recessed structure is formed between two adjacent channel regions of the plurality of channel regions. 8 . The ambient light sensor with ultraviolet light sensing function as claimed in claim 1 , wherein the visible light response band is 460 nm to 660 nm. 9 . The ambient light sensor with ultraviolet light sensing function as claimed in claim 1 , wherein the visible light sensing chip comprises a semiconductor stack structure, and the semiconductor stack structure comprises an InGaAlP material layer.

10. The ambient light sensor with ultraviolet light sensing function as described in claim 9, wherein the visible light sensing chip further includes a substrate, a first electrode layer and a second electrode layer, the semiconductor stacking structure and the first electrode layer are respectively located on two opposite sides of the substrate, the semiconductor stacking structure forms the light receiving surface on the side facing away from the substrate, and the second electrode layer is located on the light receiving surface and exposed to the wavelength conversion layer.

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