Integrated optical elements and methods for forming metasurfaces

Abstract

To provide a method for forming an integrated optical element and a metasurface.SOLUTION: An integrated optical element comprises: a light-emitting device layer; and a metasurface that includes a substrate, a plurality of conductive layers that are on the substrate, are arranged along a first direction, and each have a plurality of holes, a first dielectric layer that covers the conductive layer at equal angles, and a first transparent conductive layer that covers the first dielectric layer at equal angles, and that is on the light-emitting device layer.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] Some embodiments of the present disclosure relate to methods for forming integrated optical elements and metasurfaces. [Background technology]

[0002] Gate-tunable metasurfaces are generally reflective elements, so applying a voltage to the gate can manipulate the carrier concentration of the transparent conductive film sandwiched between the structures. By changing its optical properties, the element can provide different phase shifts at different positions, thereby adjusting the angular deflection of the reflected light beam. However, the unit antennas of gate-tunable metasurfaces are often located at wavelength positions with low reflectivity, which causes the element to operate in a band with low reflectivity, ultimately reducing the overall efficiency of the element. Summary of the Invention

[0003] Some embodiments of the present disclosure provide an optical element comprising a light-emitting element layer, a plurality of conductive layers arranged along a first direction, each having a plurality of holes, a first dielectric layer covering the conductive layers, and a first transparent conductive layer covering the first dielectric layer, and a metasurface in the light-emitting element layer.

[0004] In some embodiments, the metasurface further comprises a substrate underlying the conductive layer.

[0005] In some embodiments, the first dielectric of the metasurface is in contact with the substrate.

[0006] In some embodiments, the metasurface further includes a second transparent conductive layer between the substrate and the conductive layer, and a second dielectric layer between the second transparent conductive layer and the conductive layer.

[0007] In some embodiments, the first dielectric layer of the metasurface contacts the second dielectric layer.

[0008] In some embodiments, the holes in each of the conductive layers are arranged along a second direction that is different from the first direction.

[0009] In some embodiments, the conductive layers are arranged in a two-dimensional array.

[0010] In some embodiments, each hole in the conductive layer includes a plurality of first holes and a plurality of second holes, the first holes are arranged along a first direction and a second direction different from the first direction, one of the second holes is located between four of the first holes, and the center of one of the second holes is aligned with the center of a line connecting the centers of two adjacent first holes.

[0011] In some embodiments, one of the holes is a concave square.

[0012] In some embodiments, one of the holes comprises two circular holes connected by a rectangular hole.

[0013] Some embodiments of the present disclosure provide a method for forming a metasurface, including forming a conductive material layer on a substrate; patterning the conductive material layer to form a plurality of conductive layers on the substrate arranged along a first direction and having a plurality of holes; forming a first dielectric layer on the conductive layer; and forming a first transparent conductive layer on the first dielectric layer.

[0014] In some embodiments, when the first dielectric layer is formed on the conductive layer, the first dielectric layer extends from the sidewalls of the conductive layer to the top surface of the substrate.

[0015] In some embodiments, the method further includes forming a second transparent conductive layer on the substrate before forming the metal material layer on the substrate, and forming a second dielectric layer on the second transparent conductive layer between the second transparent conductive layer and the conductive layer.

[0016] In some embodiments, after forming the first dielectric layer on the conductive layer, the first dielectric layer extends from the sidewalls of the conductive layer to the top surface of the second dielectric layer.

[0017] In some embodiments, the holes in each of the conductive layers are aligned along the first direction.

[0018] In some embodiments, each hole in the conductive layer is further arranged along a second direction different from the first direction.

[0019] In some embodiments, the conductive layers are arranged in a two-dimensional array.

[0020] In some embodiments, each hole in the conductive layer includes a plurality of first holes and a plurality of second holes, the first holes are arranged along a first direction and a second direction different from the first direction, one of the second holes is located between four of the first holes, and the center of one of the second holes is aligned with the center of a line connecting the centers of two adjacent first holes.

[0021] In some embodiments, one of the holes is a concave square.

[0022] In some embodiments, one of the holes comprises two circular holes connected by a rectangular hole. [Brief explanation of the drawings]

[0023] [Figure 1] 1A and 1B are schematic diagrams illustrating optical elements according to some embodiments of the present disclosure. [Figure 2] FIG. 2 is a top view showing a portion of the metasurface in FIG. 1. [Figure 3] FIG. 3 illustrates a cross-sectional view of a metasurface taken along line AA in FIG. 2 according to some embodiments. [Figure 4] FIG. 3 is a cross-sectional view of a metasurface taken along line AA in FIG. 2 in some other embodiments. [Figure 5] 5A-5C are cross-sectional views illustrating a manufacturing process of the metasurface of FIG. 4 in some embodiments of the present disclosure. [Figure 6] 5A-5C are cross-sectional views illustrating a manufacturing process of the metasurface of FIG. 4 in some embodiments of the present disclosure. [Figure 7]5A-5C are cross-sectional views illustrating a manufacturing process of the metasurface of FIG. 4 in some embodiments of the present disclosure. [Figure 8] 5A-5C are cross-sectional views illustrating a manufacturing process of the metasurface of FIG. 4 in some embodiments of the present disclosure. [Figure 9] 10A-10C are cross-sectional views showing the manufacturing process of metasurfaces in some other embodiments of the present disclosure. [Figure 10] 10A-10C are cross-sectional views showing the manufacturing process of metasurfaces in some other embodiments of the present disclosure. [Figure 11] FIG. 10 is a top view of a metasurface in some other embodiments. [Figure 12] FIG. 10 is a top view of a metasurface in some other embodiments. [Figure 13] FIG. 10 is a top view of a metasurface in some other embodiments. [Figure 14] 10A-10C are top views illustrating protruding structures in some embodiments. [Figure 15] 10A and 10B are top views illustrating protruding structures in some other embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0024] Some embodiments of the present disclosure provide optical elements including metasurfaces with innovative structures. The metasurfaces of some embodiments of the present disclosure are transmissive metasurfaces, and the protruding structures of the metasurfaces have holes. Therefore, the metasurfaces of some embodiments of the present disclosure can operate at wavelengths with high transmittance, thereby improving the efficiency of the metasurfaces.

[0025] 1 is a schematic diagram illustrating an integrated optical element 100 according to some embodiments of the present disclosure. The integrated optical element 100 includes a light-emitting element layer 200 and a metasurface 300. The metasurface 300 is disposed on the light-emitting element layer 200. The light-emitting element layer 200 may be a layer including light-emitting elements of any form. For example, the light-emitting element layer 200 may include a mounting plate and light-emitting elements arranged on the mounting plate, and the light-emitting elements may be light-emitting diode chips, micro light-emitting diode chips, organic light-emitting diode chips, semiconductor laser chips, or the like.

[0026] The metasurface 300 is on the light-emitting element layer 200. In some embodiments of the present disclosure, the metasurface 300 is a transmissive metasurface. That is, light emitted from a light source is transmitted through the metasurface 300, and the metasurface 300 can change the optical properties of the light emitted from the light source. Thus, the metasurface 300 is aligned with the light-emitting element layer 200 (e.g., both emit light upward).

[0027] FIG. 2 is a top view of a portion of the metasurface 300 in FIG. 1 . The metasurface 300 includes multiple channels, e.g., channels CH1 and CH2. Each channel may include multiple protruding structures. For example, channel CH1 may include protruding structures A1 and A2, and channel CH2 may include protruding structures A3 and A4. In some embodiments, the protruding structures A1, A2, A3, and A4 include holes H, which are arranged along a first direction D1 and extend along a second direction D2. In some embodiments, each protruding structure includes a row of holes H. Each hole H is a unit antenna. The size of the holes H can determine the range of optical wavelengths that can pass through the metasurface 300. In some embodiments, the holes H are subwavelength structures, and the diameter of the holes H is between about 1 / 10 and 1 / 2 of the wavelength of the incident light.

[0028] The metasurface 300 is used to change the deflection angle of incident light. After light enters the metasurface 300 from below the metasurface 300, the deflection angle is θ=sin -1 This can be expressed by the relationship (λ / Λ). θ is the deflection angle, λ is the wavelength of the incident light, and Λ is the width of the large period of the metasurface 300. Here, "large period" refers to the total width of a specific number of channels. For example, the channels CH1 and CH2 in FIG. 2 can constitute one large period Λ2, and the channels CH1 and CH2 in the large period Λ2 can be used to adjust and control the same deflection angle. Therefore, a specific large period can be selected for a specific deflection angle and a corresponding voltage can be applied, and different voltages are applied to different channels in the large period (e.g., channels CH1 and CH2 in the large period Λ2). Applying voltages to the channels changes the carrier concentration of the transparent conductive layer of the channel, which in turn changes the optical properties of the channel. When different voltages are applied to different channels in the large period, the carrier concentrations of the transparent conductive layer between the different channels are different (e.g., gradually change along the first direction D1), resulting in different optical properties between the different channels. In this way, the metasurface 300 can provide different phase shifts at different positions, thereby adjusting and controlling the angular deflection of the incident beam.

[0029] The number of channels in each large period can determine the granularity of the beam adjustment control capability. For example, the more channels in each large period, the more granular the beam adjustment control capability. In some embodiments, each large period may include two channels, e.g., channel CH1 and channel CH2, where channel CH1 may include protruding structures A1 and A2, and channel CH2 may include protruding structures A3 and A4. However, the present disclosure is not limited thereto.

[0030] FIG. 3 illustrates a cross-sectional view of a metasurface 300 taken along line AA in FIG. 2 according to some embodiments. The metasurface 300 includes a substrate 310, a conductive layer 340, a dielectric layer 350, and a transparent conductive layer 360. Specifically, the conductive layer 340 is on and in contact with the substrate 310. The conductive layer 340 may have a specific shape, and the conductive layer 340 has holes H. The conductive layer 340 may be used to determine the shape of the protruding structures A1, A2, A3, and A4 ( FIG. 2 ). The dielectric layer 350 conformally covers the conductive layer 340, and the transparent conductive layer 360 conformally covers the dielectric layer 350. In some embodiments, the dielectric layer 350 also conformally covers the substrate 310, so that the dielectric layer 350 extends along the top surface of the substrate 310 to the sidewalls and top surface of the conductive layer 340. That is, the conductive layer 340 is sandwiched between the dielectric layer 350 and the substrate 310. The conductive layer 340 and the transparent conductive layer 360 are made of different conductive materials, and the conductive materials of the conductive layer 340 and the transparent conductive layer 360 have different carrier concentrations. The carrier concentration of the conductive layer 340 is greater than the carrier concentration of the transparent conductive layer 360; for example, the carrier concentration of the conductive layer 340 itself is greater than the carrier concentration of the transparent conductive layer 360 by two or more orders of magnitude. In some embodiments, the carrier concentration of the conductive layer 340 is on the order of 10 22 pieces / m 3 The carrier concentration of the transparent conductive layer 360 is on the order of 10 20 pieces / m 3 3. Note that FIG. 3 is a cross-sectional view showing only protruding structure A1. Cross-sectional views of other protruding structures may also be shown in FIG. 3. Accordingly, metasurface 300 may include multiple conductive layers 340, which are arranged on substrate 310 along a first direction D1, and each of conductive layers 340 has multiple holes H, as shown in FIG. 2. Furthermore, because the transparent conductive layers 360 on each protruding structure are not connected to each other, the transparent conductive layers 360 on each protruding structure can be independently adjusted and controlled in subsequent operations.

[0031] The metasurface 300 in FIG. 3 is a single-gate structure, i.e., the voltage V u may be applied to the transparent conductive layer 360, and a voltage V g (V gA voltage V applied to the transparent conductive layer 360 of the different channels (V is generally a ground voltage) may be applied to the conductive layer 340, so that the carrier concentration on the side of the transparent conductive layer 360 closer to the dielectric layer 350 can be adjusted and controlled. u Because the phases of the transparent conductive layers are different, the carrier concentrations of the transparent conductive layers in the different channels are different (e.g., gradually varying along the first direction D1 in FIG. 2 ), and thus the optical properties of the different channels are different. In this manner, metasurface 300 can provide different phase compensation at different positions, thereby enabling tuning and control of the angular deflection of the incident beam. In this embodiment, the channels are arranged along the first direction D1 ( FIG. 2 ), i.e., the channels constitute a one-dimensional metasurface, which may provide one-dimensional tuning control of the angular deflection of the incident beam.

[0032] In the present disclosure, metasurface 300 is a transmissive metasurface, and protruding structures A1, A2, A3, and A4 of metasurface 300 have holes H. Reflective metasurfaces are typically designed at wavelengths with low reflectivity, resulting in low metasurface efficiency and prone to excess stray light and high-order diffraction. In contrast, these holes H in metasurface 300 are anti-structures designed based on Babinet's principle. The plasma resonance mode induced by the holes H is located at wavelengths with high transmittance, thereby improving the overall efficiency of metasurface 300. Furthermore, because conductive layer 340 of metasurface 300 of the present disclosure has holes H and the holes H are subwavelength structures, the occurrence of high-order diffraction (e.g., lattice diffraction) can be avoided. This improves the quality of the transmitted beam. Furthermore, because metasurface 300 of the present disclosure is a transmissive metasurface, it can be easily combined with a light-emitting element layer to form integrated optical element 100 (Figure 1). When the metasurface is a reflective metasurface, a light-emitting element layer is located on the metasurface. If the integrated optical element is to maintain upward light emission, the presence of the light-emitting element layer imposes many design constraints.

[0033] FIG. 4 illustrates a cross-sectional view of a metasurface 300 taken along line AA in FIG. 2 according to some other embodiments. The metasurface 300 in FIG. 4 is similar to the metasurface 300 in FIG. 3, except that the metasurface 300 in FIG. 4 further includes a transparent conductive layer 320 and a dielectric layer 330. The transparent conductive layer 320 is between the substrate 310 and the conductive layer 340, and the dielectric layer 330 is between the transparent conductive layer 320 and the conductive layer 340. The conductive layer 340 is in contact with the dielectric layer 330 but not with the substrate 310. The dielectric layer 350 conformally covers the conductive layer 340, and the transparent conductive layer 360 conformally covers the dielectric layer 350. In some embodiments, the dielectric layer 350 also conformally covers the dielectric layer 330, so that the dielectric layer 350 extends along the top surface of the dielectric layer 330 and to the sidewalls and top surface of the conductive layer 340. The conductive layer 340 and the transparent conductive layers 320, 360 are made of different conductive materials, and the conductive materials of the conductive layer 340 and the transparent conductive layers 320, 360 have different carrier concentrations. The carrier concentration of the conductive layer 340 is greater than the carrier concentration of the transparent conductive layers 320, 360; for example, the carrier concentration of the conductive layer 340 itself is greater than the carrier concentration of the transparent conductive layers 320, 360 by two or more orders of magnitude. In some embodiments, the carrier concentration of the conductive layer 340 is on the order of 10 22 pieces / m 3 The carrier concentration of the transparent conductive layers 320 and 360 is on the order of 10 20 pieces / m 3 4. Note that FIG. 4 is a cross-sectional view showing only the protruding structure A1. Cross-sectional views of other protruding structures may also be shown in FIG. 4. Accordingly, the metasurface 300 may include multiple conductive layers 340, which are arranged on the substrate 310 along a first direction D1, and each of the conductive layers 340 has multiple holes H, as shown in FIG. 2. Furthermore, because the transparent conductive layers 360 on each protruding structure are not connected to each other and the transparent conductive layers 320 under each protruding structure are not connected to each other, the transparent conductive layers 360 on each protruding structure and the transparent conductive layers 320 under each protruding structure can be independently adjusted and controlled in subsequent operations.

[0034] The metasurface 300 in FIG. 4 has a double-gate structure, i.e., different voltages V u and Vb may be applied to the transparent conductive layer 360 and the transparent conductive layer 320, respectively, and a voltage V g (V g A voltage V applied to the transparent conductive layer 320 of the different channels can be adjusted and controlled by applying a voltage V to the conductive layer 340. The voltage V is generally a ground voltage, and the carrier concentration of the transparent conductive layer 360 on the side closer to the dielectric layer 350 and the carrier concentration of the transparent conductive layer 320 on the side closer to the dielectric layer 330 can be adjusted and controlled. b V applied to the transparent conductive layer 360 of the different channels u Because the channels are different, the carrier concentrations of the transparent conductive layer between different channels are different (e.g., gradually varying along the first direction D1 in FIG. 2 ), and thus the optical properties between different channels are different. In this way, metasurface 300 can provide different phase compensation at different positions, thereby enabling tuning and control of the angular deflection of an incident beam. In some embodiments, metasurface 300 with a double-gate structure can provide better beam tuning control than metasurface 300 with a single-gate structure. In this embodiment, because the channels are arranged along the first direction D1 ( FIG. 2 ), i.e., the channels form a one-dimensional metasurface, one-dimensional tuning control of the angular deflection of an incident beam can be achieved.

[0035] 5-8 are cross-sectional views illustrating a fabrication process for the metasurface 300 of FIG. 4 in some embodiments of the present disclosure. Referring to FIG. 5, a substrate 310 is provided, a transparent conductive layer 320 is formed on the substrate 310, and then a dielectric layer 330 is formed on the transparent conductive layer 320. The transparent conductive layer 320 and the dielectric layer 330 are planar layers on the substrate 310. In some embodiments, the substrate 310 may be a glass substrate or other transparent substrate, allowing a light source below to pass through the metasurface 300. In some embodiments, the transparent conductive layer 320 may be indium tin oxide (ITO) or other suitable transparent conductive material. The dielectric layer 330 may be a high-k material such as Al2O3 or HfO2. In some embodiments, the dielectric layer 330 may be formed by atomic layer deposition.

[0036] Referring to FIG. 6, a metal material layer 340′ is formed on the dielectric layer 330. Next, referring to FIG. 7, the metal material layer 340′ is patterned to form a conductive layer 340. The conductive layer 340 is arranged along a first direction (e.g., the first direction D1 in FIG. 2) and has a plurality of holes H. Specifically, the patterned conductive layer 340 is formed as a plurality of protruding structures (e.g., the protruding structures A1, A2, A3, and A4 in FIG. 2), and each protruding structure has a plurality of holes H. The shape of the conductive layer 340 and the diameter of the holes H may be determined according to actual conditions. In some embodiments, the conductive layer 340 may be made of an appropriate material depending on the wavelength of light to be applied. For example, if the metasurface 300 is applied to infrared light, the conductive layer 340 may be made of gold; if the metasurface 300 is applied to ultraviolet light, the conductive layer 340 may be made of aluminum; and if the metasurface 300 is applied to blue light, the conductive layer 340 may be made of silver.

[0037] Referring to FIG. 8 , a dielectric layer 350 is formed on the conductive layer 340. After forming the dielectric layer 350 on the conductive layer 340, the dielectric layer 350 extends from the sidewalls of the conductive layer 340 to the top surface of the dielectric layer 330. The dielectric layer 350 and the dielectric layer 330 sandwich and surround the conductive layer 340. Next, a transparent conductive layer 360 is formed on the dielectric layer 350. In some embodiments, the dielectric layer 350 may be a high-k material such as Al2O3 or HfO2. In some embodiments, the dielectric layer 350 may be formed by atomic layer deposition. The transparent conductive layer 360 may be indium tin oxide or another suitable transparent conductive material. After forming the metasurface 300, the metasurface 300 may be placed on the light-emitting element layer 200. Thus, the metasurface 300 may be used to adjust and control the physical properties of the light emitted by the light-emitting element layer 200.

[0038] The manufacturing process for the metasurface 300 in Figure 3 is similar to the manufacturing processes shown in Figures 5 to 8. When manufacturing the metasurface 300 in Figure 3, the transparent conductive layer 320 and the dielectric layer 330 in Figure 5 can be omitted. Therefore, in Figure 6, a metal material layer 340' can be directly formed on the substrate 310, and subsequent processes can be continued. When manufacturing the metasurface 300 in Figure 3, the dielectric layer 350 is formed on the conductive layer 340, and then the dielectric layer 350 extends from the sidewall of the conductive layer 340 to the top surface of the substrate 310. The dielectric layer 350 and the substrate 310 sandwich and surround the conductive layer 340.

[0039] 9 and 10 are cross-sectional views illustrating a manufacturing process of a metasurface 300 according to some other embodiments of the present disclosure. In FIG. 9 and FIG. 10, the metasurface 300 may be formed directly on the light-emitting element layer 200. Specifically, referring to FIG. 9, a dielectric layer 250 is formed on the light-emitting element layer 200. The dielectric layer 250 may be made of silicon oxide, silicon nitride, etc.

[0040] Referring to FIG. 10, a metasurface 300 is formed on the dielectric layer 250. The method for forming the metasurface 300 is similar to the manufacturing process shown in FIGS. 5 to 8. In FIG. 10, the difference is that a transparent conductive layer 320 is formed on the dielectric layer 250. In this way, the metasurface 300 may be formed directly on the light-emitting element layer 200.

[0041] FIG. 11 is a top view of a metasurface 300 according to some other embodiments. The metasurface 300 of FIG. 11 is similar to the metasurface 300 of FIG. 2, but the number of channels included in the metasurface 300 of FIG. 11 is different from the number of channels included in the metasurface 300 of FIG. 2, and the number of holes H included in each protruding structure of the metasurface 300 of FIG. 11 is also different from the number of holes H included in each protruding structure of the metasurface 300 of FIG. 2. For example, the channels CH1, CH2, and CH3 in FIG. 11 can form one large period Λ3. In this embodiment, different voltages are applied to the channels CH1, CH2, and CH3, resulting in different optical properties between the different channels. In this way, the metasurface 300 can provide different phase compensation at different positions, thereby enabling adjustment and control of the angular deflection of the incident beam. Increasing the number of channels included in each large period allows for finer adjustment and control of the angular deflection of the incident beam. Additionally, each protruding structure of the metasurface 300 of FIG. 11 includes two rows of holes H. The number of holes H in each protruding structure may be designed according to the actual situation.

[0042] FIG. 12 is a top view illustrating a metasurface 300 according to some other embodiments. The metasurface 300 in FIG. 12 is similar to the metasurface 300 in FIG. 11 . The difference is that the holes H in FIG. 12 include a first hole H1 and a second hole H2, where the first hole H1 is arranged along the first direction D1 and the second direction D2, the second hole H2 is arranged between four holes H1, and the center of the second hole H2 is aligned with the center of the line connecting the centers of two adjacent first holes H1. Therefore, increasing the number of holes H per unit area improves the tuning control ability of the metasurface 300 to the beam.

[0043] FIG. 13 is a top view illustrating a metasurface 300 according to some other embodiments. The metasurface 300 of FIG. 13 includes multiple channels CH1, CH2, CH3, CH4, CH5, CH6, CH7, CH8, and CH9, each of which may include a protruding structure. The protruding structures are arranged along a first direction D1 as well as a second direction D2 perpendicular to the first direction D1. Thus, in FIG. 13, the channels (i.e., the protruding structures) of the metasurface 300 are arranged in a two-dimensional array in a planar view. In this manner, different voltages are applied to the channels CH1, CH2, CH3, CH4, CH5, CH6, CH7, CH8, and CH9 in FIG. 13, resulting in different optical properties between the different channels. In this manner, the metasurface 300 can provide different phase shifts at different positions, thereby enabling adjustment and control of the angular deflection of an incident beam. When the metasurface 300 is configured in two dimensions using the channels, two-dimensional adjustment and control of the angular deflection of an incident beam can be achieved.

[0044] 14 is a top view showing a protruding structure AN in some embodiments. The protruding structure AN in FIG. 14 may have a dumbbell-shaped hole H. Specifically, the hole H is two circular holes connected by a rectangular hole. The protruding structure AN itself is rectangular, and the length P of the protruding structure A in the first direction D1 is x is 400 nm, and the length P y The diameter is 600 nm and the thickness is 100 nm. The width W of the dumbbell neck of the hole H is 100 nm. When the protruding structure AN has the above shape, the protruding structure AN can operate at a wavelength position with high transmittance. For example, when the protruding structure AN of Figure 14 is used to adjust and control the deflection angle of an incident beam, the wavelength of the incident beam is approximately 1.5 μm, the transmittance of the incident beam can reach 92%, and the phase adjustment control ability can reach 141.6 degrees. The protruding structures AN can be arranged in a one-dimensional or two-dimensional array, so the metasurface composed of the protruding structures AN can adjust and control the angular deflection of the incident beam in one or two dimensions.

[0045] Fig. 15 is a top view showing a protruding structure AN in some other embodiments. The protruding structure AN in Fig. 15 may have a boomerang-shaped hole H. Specifically, the hole H may be a concave rectangle. In some embodiments, as shown in Fig. 15, the four corners of the concave rectangle are formed by straight lines. In other embodiments, the four corners of the concave rectangle may be rounded.

[0046] As described above, the transmissive metasurfaces of some embodiments of the present disclosure have various advantages. Because the metasurfaces have holes and these holes may be designed based on Babinet's principle, the resulting plasma resonance modes are located at wavelengths with high transmittance, which contributes to improving the overall efficiency of the metasurfaces. Furthermore, the conductive layers of the metasurfaces of the present disclosure have holes, and because the holes have a subwavelength structure, they may be used to avoid high-order diffraction (e.g., lattice diffraction). This improves the quality of the transmitted beam. Furthermore, because the metasurfaces of the present disclosure are transmissive metasurfaces, they can be easily combined with light-emitting element layers to form integrated optical elements. The light-emitting element layer does not interfere with the light-emitting direction of the integrated optical element.

[0047] The above are only some embodiments of the present disclosure, not all embodiments, and all equivalent modifications made by those skilled in the art to the technical solutions of the present disclosure after reading the specification of the present disclosure belong to the scope of the claims of the present disclosure. [Explanation of symbols]

[0048] 100 Integrated Optical Elements 200 Light emitting element layer 250 dielectric layers 300 Metasurface 310 Substrate 320 Transparent conductive layer 330 Dielectric Layer 340 Conductive Layer 340' metal material layer 350 dielectric layer 360 Transparent conductive layer AA line A, A1, A2, A3, A4, AN protruding structure CH1~CH9 channels D1 1st direction D2 2nd direction H hole H1 1st hole H2 2nd hole P x length P y length W width

Claims

1. a light-emitting element layer; a metasurface on the light-emitting element layer, A substrate; a plurality of conductive layers arranged along a first direction on the substrate, the substrate being between the plurality of conductive layers and the light-emitting element layer, each of the plurality of conductive layers having a plurality of holes; a first dielectric layer conformally covering the hole in one of the plurality of conductive layers; a first transparent conductive layer conformally covering the first dielectric layer and the hole in the one conductive layer of the plurality of conductive layers; a metasurface including: An integrated optical element comprising:

2. The integrated optical element of claim 1 , wherein the first dielectric layer of the metasurface is in contact with the substrate.

3. The metasurface is a second transparent conductive layer between the substrate and the conductive layer; a second dielectric layer between the second transparent conductive layer and the conductive layer; The integrated optical element of claim 1 further comprising:

4. The integrated optical element of claim 3 , wherein the first dielectric layer of the metasurface is in contact with the second dielectric layer.

5. The integrated optical element according to claim 1 , wherein the holes in each of the conductive layers are arranged along a second direction different from the first direction.

6. The integrated optical element according to claim 1 , wherein the conductive layers are arranged in a two-dimensional array.

7. 2. The integrated optical element of claim 1, wherein each of the holes in the conductive layer includes a plurality of first holes and a plurality of second holes, the first holes are arranged along the first direction and a second direction different from the first direction, each of the second holes is located between four of the first holes, and the center of each of the second holes is aligned with the center of a line connecting the centers of two adjacent first holes.

8. 2. The integrated optical element of claim 1, wherein each of said holes is a concave square.

9. 2. The integrated optical element of claim 1, wherein each of said holes comprises two circular holes connected by a rectangular hole.

10. forming a substrate on the light-emitting element layer; forming a layer of conductive material on the substrate; patterning the conductive material layer to form a plurality of conductive layers on the substrate arranged along a first direction and having a plurality of holes; conformally forming a first dielectric layer on the conductive layer; conformally forming a first transparent conductive layer over the first dielectric layer and the hole in one of the plurality of conductive layers; A method for forming a metasurface, comprising:

11. 11. The method of claim 10, wherein forming the first dielectric layer on the conductive layer comprises extending the first dielectric layer from a plurality of sidewalls of the conductive layer to a top surface of the substrate.

12. before forming the conductive material layer on the substrate; forming a second transparent conductive layer on the substrate; forming a second dielectric layer on the second transparent conductive layer, the second dielectric layer being between the second transparent conductive layer and the conductive layer; The method of claim 10 further comprising:

13. 13. The method of claim 12, further comprising forming the first dielectric layer on the conductive layer, and then extending the first dielectric layer from a plurality of sidewalls of the conductive layer to a top surface of the second dielectric layer.

14. The method of claim 10 , wherein the holes in each of the conductive layers are aligned along a first direction.

15. The method of claim 10 , wherein the holes in each of the conductive layers are further arranged along a second direction different from the first direction.

16. The method of claim 10 , wherein the conductive layers are arranged in a two-dimensional array.

17. 11. The method of claim 10, wherein the holes in each of the conductive layers include a plurality of first holes and a plurality of second holes, the first holes are arranged along the first direction and a second direction different from the first direction, each of the second holes is located between four of the first holes, and the center of each of the second holes is aligned with the center of a line connecting the centers of two adjacent first holes.

18. The method of claim 10 , wherein each of the holes is a concave square.

19. The method of claim 10 , wherein each of the holes comprises two circular holes connected by a rectangular hole.

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