Coupling device and electronic device comprising the same

Abstract

A coupling device includes a substrate including a first surface to a third surface, and a first coupling waveguide including a first waveguide including a first end portion and a second end portion in the third surface, wherein the first end portion is exposed at the first surface, the second end portion is inside the substrate, and the first waveguide further includes a transmission path from the first end portion to the second end portion in a first direction parallel to the third surface, and a second waveguide including a third end portion and a fourth end portion, wherein the third end portion is adjacent to the first waveguide inside the substrate, the fourth end portion is exposed at a second surface, and a distance from the third surface to the third end portion is different from a distance from the third surface to the fourth end portion.

Description

Cross-reference to related applications

[0001] This application is based on and claims priority to Korean Patent Application No. 10-2024-0175807, filed with the Korean Intellectual Property Office on November 29, 2024, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] This disclosure relates to a coupling device and an electronic device including the coupling device. Background Technology

[0003] Optical interconnect is a technology that converts electrical data into optical signals and transmits those signals. It originated in the 1980s with intercontinental (thousands of kilometers) optical communication and has since expanded to shorter distances, including connecting cities (tens to hundreds of kilometers), data centers (kilometers to tens of kilometers), and racks within data centers (tens to several kilometers). This is due to the exponential growth in data transmission demands.

[0004] Electrical interconnects transmit charge via copper wires, but a problem arises: the skin effect, where the wire resistance increases with transmission speed, leads to reduced power efficiency. Optical interconnects, however, do not suffer from this problem. Therefore, for long-distance communication, optical interconnects, with their significant advantages, have replaced electrical interconnects.

[0005] In this type of optical communication, light transmitted through optical fibers can be converted back into electrical signals. Therefore, various technologies have been explored to connect optical fibers to photonic integrated circuits (PICs) equipped with optical elements for photoelectric conversion. Summary of the Invention

[0006] A coupling device is provided for connecting optical fibers to photonic integrated circuits (PICs).

[0007] According to one aspect of this disclosure, a coupling device may include: a substrate including a first surface, a second surface, and a third surface, wherein the first surface and the second surface are back-to-back with each other, and the third surface is between and connected to the first surface and the second surface; and a first coupling waveguide within the substrate and extending from the first surface to the second surface, wherein the first coupling waveguide includes: a first waveguide in the third surface of the substrate, the first waveguide including a first end and a second end, wherein the first end is exposed on the first surface, the second end is inside the substrate, and the first waveguide further includes a transmission path from the first end to the second end in a first direction parallel to the third surface; and a second waveguide including a third end and a fourth end, wherein the third end is adjacent to the first waveguide inside the substrate, the fourth end is exposed on the second surface, and the distance from the third surface to the third end is different from the distance from the third surface to the fourth end.

[0008] The refractive indices of the first waveguide and the second waveguide can be different from each other.

[0009] The difference between the refractive index of the first waveguide and the refractive index of the second waveguide can be 0.003 or less.

[0010] The third end of the second waveguide can be adjacent to the first waveguide, so that light propagating through the second waveguide can be transmitted to the first waveguide.

[0011] A portion of the first waveguide and a portion of the second waveguide may overlap each other in a second direction in the substrate, which is parallel to the third surface and perpendicular to the first direction.

[0012] The distance between a portion of the first waveguide and a portion of the second waveguide in the second direction can be 3 μm or less.

[0013] The overlap length between a portion of the first waveguide and a portion of the second waveguide can be from 0.1 mm to 5 mm.

[0014] Parts of the first waveguide and parts of the second waveguide can overlap each other in the substrate in a third direction perpendicular to the third surface.

[0015] The length of the first waveguide in the first direction can be 50% or more of the length of the substrate in the first direction.

[0016] The first coupling waveguide may further include a directional coupler between the first waveguide and the second waveguide, wherein the directional coupler extends parallel to the first waveguide and the material of the directional coupler is the same as that of the first waveguide.

[0017] One end of the directional coupler can contact the third end.

[0018] The first waveguide can be formed by implanting ions into the material of the substrate.

[0019] A second waveguide can be formed by using a laser to modify the material of a substrate.

[0020] According to one aspect of this disclosure, the coupling device may further include a second coupling waveguide, the second coupling waveguide comprising: a third waveguide in a third surface of a substrate, the third waveguide including a fifth end and a sixth end, wherein the fifth end is exposed on a first surface, the sixth end is located inside the substrate, and the third waveguide further includes a transmission path from the fifth end to the sixth end in a first direction; and a fourth waveguide including a seventh end and an eighth end, wherein the seventh end is adjacent to the third waveguide inside the substrate, the eighth end is exposed on a second surface, and the distance from the third surface to the seventh end is different from the distance from the third surface to the eighth end, and wherein the distance from the third surface to the eighth end is different from the distance from the third surface to the fourth end.

[0021] The coupling device may also include a third waveguide extending from the first surface to the second surface, the distance between the third waveguide and the third surface being constant, and the material of the third waveguide being the same as that of the first waveguide.

[0022] The coupling device may also include alignment marks on the third surface of the substrate.

[0023] The coupling device may also include a guide pin hole in the substrate and through an opening on a second surface of the substrate.

[0024] A method of manufacturing a coupling device may include: forming a first waveguide in a substrate, the first waveguide including a first transmission path, wherein the distance from the surface of the substrate to the first transmission path is constant; and forming a second waveguide in the substrate, the second waveguide including a second transmission path, wherein the distance from the surface of the substrate to the second transmission path is not constant.

[0025] Forming the first waveguide may include ion implantation, and forming the second waveguide may include laser beam irradiation.

[0026] According to one aspect of this disclosure, an electronic device may include: a coupling device; an optical fiber array connected to a first end of the coupling device; and a photonic integrated circuit connected to a second end of the coupling device, wherein the coupling device includes: a substrate including a first surface, a second surface, and a third surface, wherein the first surface and the second surface are back-to-back with each other, and the third surface is between and connected to the first surface and the second surface; and a coupling waveguide within the substrate and extending from the first surface to the second surface, wherein the coupling waveguide includes: a first waveguide in the third surface, the first waveguide including a first end and a second end, wherein the first end is exposed on the first surface, the second end is inside the substrate, and the first waveguide further includes a transmission path from the first end to the second end in a first direction parallel to the third surface; and a second waveguide including a third end and a fourth end, wherein the third end is adjacent to the first waveguide within the substrate, the fourth end is exposed on the second surface, and the distance from the third surface to the third end is different from the distance from the third surface to the fourth end.

[0027] Additional aspects will be set forth in part in the description which follows, and will also be apparent in part from the description, or may be learned by practicing the embodiments presented in this disclosure. Attached Figure Description

[0028] The above and other aspects, features, and advantages of some embodiments of this disclosure will become clearer from the following description taken in conjunction with the accompanying drawings, in which:

[0029] Figure 1 This is a perspective view showing a schematic structure of the coupling device according to an embodiment;

[0030] Figure 2A It shows Figure 1 A detailed perspective view of the coupling waveguides installed in the coupling device;

[0031] Figure 2B and Figure 2C They are shown separately Figure 1 Side view of the first and second surfaces of the coupling device;

[0032] Figure 3 It shows in Figure 1 The electromagnetic field distribution at the locations where the first waveguide and the second waveguide are adjacent to each other in the coupling device is calculated and simulated.

[0033] Figure 4 This is a perspective view showing a schematic structure of the coupling device according to an embodiment;

[0034] Figure 5A and Figure 5B They are shown separately Figure 4Side view of the first and second surfaces of the coupling device;

[0035] Figure 6A and Figure 6B These are side views showing the first and second surfaces of the coupling device according to an embodiment;

[0036] Figure 7 This is a perspective view showing a schematic structure of the coupling device according to an embodiment;

[0037] Figure 8 It shows Figure 7 A detailed perspective view of the coupling waveguides installed in the coupling device;

[0038] Figure 9 This is a detailed perspective view showing the coupling waveguide disposed in the coupling device according to an embodiment;

[0039] Figure 10 This is a flowchart illustrating a method for manufacturing a coupling device according to an embodiment;

[0040] Figure 11 A block diagram schematically illustrating an electronic device according to an embodiment; and

[0041] Figure 12 An electronic device according to an embodiment is illustrated schematically. Detailed Implementation

[0042] The non-limiting exemplary embodiments of this disclosure will now be described in detail with reference to the accompanying drawings, wherein similar reference numerals always indicate similar elements. In this respect, embodiments of this disclosure may take different forms and should not be construed as limited to the description set forth herein. Accordingly, exemplary embodiments are described below only with reference to the accompanying drawings to explain exemplary aspects. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of…” modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list.

[0043] In the following, non-limiting exemplary embodiments of the present disclosure are described in detail with reference to the accompanying drawings. The exemplary embodiments described below are merely illustrative, and various modifications can be made to these embodiments. In the drawings, the same reference numerals indicate the same components, and the dimensions of each component in the drawings may be exaggerated for clarity and ease of description.

[0044] It will be understood that when an element or layer is referred to as being "on" or "above" another element or layer, that element or layer may be directly on the other element or layer, or on an intermediate element or layer.

[0045] Terms such as “first” and “second” can be used to describe various components, but only for the purpose of distinguishing the components from one another. These terms do not limit the differences in the materials or structures of the components.

[0046] Unless the context clearly indicates otherwise, singular expressions include plural expressions. Furthermore, when a part “contains” or “includes” a component, unless otherwise stated, this means that it may include other components, rather than exclude them.

[0047] In addition, the terms "unit" and "module" refer to a unit that performs at least one function or operation, which can be implemented by hardware or software or by a combination of hardware and software.

[0048] The term “the” and similar indicative terms can be used in both singular and plural forms.

[0049] Unless explicitly stated otherwise, the operations constituting the methods of this disclosure may be performed in an appropriate order. Furthermore, all descriptive terms (e.g., “etc.”) are used only to elaborate on exemplary aspects, and the scope of the claims is not limited by these terms.

[0050] Figure 1 This is a perspective view showing a schematic structure of the coupling device 100 according to an embodiment. Figure 2A It shows Figure 1 A detailed perspective view of the coupling waveguide provided in the coupling device 100. Figure 2B and Figure 2C They are shown separately Figure 1 Side view of the first and second surfaces of the coupling device 100.

[0051] The coupling device 100 can be configured to connect two different types of waveguides and may include a substrate 110 and a coupling waveguide 140 disposed in the substrate 110. The coupling device 100 can, for example, optically connect a waveguide providing an optical transmission path along the A2 direction to a waveguide providing an optical transmission path along the A1 direction. The coupling device 100 may include one or more coupling waveguides 140. The number of coupling waveguides 140 illustrated is merely an example and can be varied.

[0052] The substrate 110 may include a first surface 110a and a second surface 110b facing away from each other, and a third surface 110c connecting the first surface 110a and the second surface 110b between the first surface 110a and the second surface 110b. The third surface 110c may be referred to as the top surface of the substrate 110. Although the substrate 110 is shown in a cuboid shape, the embodiment is not limited thereto. The substrate 110 may include glass. The substrate 110 may also include various transparent plastic materials.

[0053] The coupled waveguide 140 may include a first waveguide 141 and a second waveguide 142.

[0054] The first waveguide 141 can be configured to insert into the interior of the substrate 110 from the third surface 110c. That is, the top surface of the first waveguide 141 can be coplanar with the third surface 110c, where the third surface 110c can be the top surface of the substrate 110. The first waveguide 141 can include a first end E1 and a second end E2. The first end E1 can be exposed at the first surface 110a, while the second end E2 can be located inside the substrate 110. The first waveguide 141 can have a refractive index different from that of the substrate 110. The refractive index of the first waveguide 141 can be greater than that of the substrate 110. The first waveguide 141 can form a transmission path at a constant distance from the third surface 110c. That is, the first waveguide 141 can extend parallel to the third surface 110c. The first waveguide 141 can form a transmission path in a first direction (e.g., the X direction). The first waveguide 141 can include a material obtained by ion implantation into the material forming the substrate 110. In other words, the first waveguide 141 can be fabricated by implanting ions into the substrate 110 at the location where the first waveguide 141 is to be formed. This fabrication method is called photolithography. As shown, the waveguide fabricated in this way forms a transmission path parallel to the third surface 110c of the substrate 110, but does not form a transmission path leading to other depths within the substrate 110.

[0055] The second waveguide 142 can be arranged adjacent to the first waveguide 141. The second waveguide 142 may include a third end E3 and a fourth end E4. The third end E3 may be inside the substrate 110 adjacent to the first waveguide 141, while the fourth end E4 may be exposed at the second surface 110b. The distances between the third end E3 and the fourth end E4 and the third surface 110c may be different from each other. The height position of the fourth end E4 may be different from the height position of the third end E3. In other words, the second waveguide 142 can form a transmission path with a non-constant distance from the third surface 110c. As shown, a portion of the second waveguide 142 can form a transmission path parallel to the third surface 110c, while the remaining portion of the second waveguide 142 can form a transmission path with a gradually increasing distance from the third surface 110c.

[0056] As shown in the figure, the third end E3 can have the same height as the second end E2 and the first end E1. This arrangement is an example of coupling between the first waveguide 141 and the second waveguide 142 occurring in the Y direction parallel to the third surface 110c, but the embodiment is not limited thereto. In an embodiment, the second waveguide 142 can be located below the first waveguide 141, and the third end E3 can be located at a lower position than the first end E1 and the second end E2, that is, it can be located within the substrate 110 at a position farther from the third surface 110c. In this case, coupling between the first waveguide 141 and the second waveguide 142 can occur in the Z direction perpendicular to the third surface 110c.

[0057] The refractive index of the second waveguide 142 can be greater than that of the substrate 110. The second waveguide 142 may comprise a material obtained by modifying the material forming the substrate 110 using a laser. In other words, the second waveguide 142 can be manufactured by focusing a laser beam at the location within the substrate 110 where the second waveguide 142 is to be formed, and using high energy to melt the material forming the substrate 110 to change its refractive index. This manufacturing method is called writing. In this way, the focus of the laser beam can be formed at a desired location within the substrate 110, thereby forming a three-dimensional transmission path, the distance from which to the third surface 110c (which may be the top surface of the substrate 110) can be set differently.

[0058] The positional relationship between the first waveguide 141 and the second waveguide 142 can be configured so that light propagating through the second waveguide 142 can be transmitted to the first waveguide 141. For example, light incident on the second waveguide 142 through the fourth end E4 can be transmitted to the first waveguide 141 at a position adjacent to the second waveguide 142. Figure 2A As shown in detail, the first waveguide 141 and the second waveguide 142 can be positioned such that some regions of them overlap when viewed from a second direction (Y direction). The second direction can be parallel to the third surface 110c of the substrate 110 and perpendicular to the first direction (e.g., the X direction), where the first direction is the direction of the transmission path of the first waveguide 141. The overlap length d1 can be from about 0.1 mm to 5 mm. At the overlap location, the distance d2 between the first waveguide 141 and the second waveguide 142 can be about 3 μm or less. These values ​​are merely examples and can be changed to appropriate values ​​that allow the first waveguide 141 and the second waveguide 142 to couple.

[0059] Although the first waveguide 141 and the second waveguide 142 can be manufactured based on the same material, they may include different materials due to different specific manufacturing methods, and therefore may have different refractive indices. The difference between the refractive index of the first waveguide 141 and the refractive index of the second waveguide 142 may be about 0.003 or less. This value is merely an example and can be changed to an appropriate value that allows the first waveguide 141 and the second waveguide 142 to couple.

[0060] The coupling device 100 may further include an alignment mark 180. The alignment mark 180 may be formed at a location introduced into the substrate 110 from the third surface 110c of the substrate 110. The alignment mark 180 may be configured to provide an alignment reference when the second waveguide 142 is formed after the first waveguide 141 is formed, or when the first waveguide 141 is formed after the second waveguide 142 is formed.

[0061] Alignment marks 180 may be manufactured together with the first waveguide 141. Alignment marks 180 may include the same material as the first waveguide 141. The position or number of alignment marks 180 is illustrative and is not limited to the form shown.

[0062] Alignment mark 180 may include a material different from that of the first waveguide 141. For example, alignment mark 180 may include a photoresist material and a metallic material, and may be manufactured separately from the process of forming the first waveguide 141.

[0063] The coupling device 100 may further include a guide pin hole 190. The guide pin hole 190 may be a hole formed inside the substrate 110, such that the hole passes through an opening on the second surface 110b. For example, guide pins of an optical fiber array may be coupled to the guide pin hole 190. The location or number of guide pin holes 190 are merely examples and are not limited to the forms shown. The guide pin hole 190 may be disposed separately from the substrate 110. For example, a socket with the guide pin hole 190 may be coupled to the substrate 110.

[0064] The coupling device 100 according to the embodiment can connect different types of waveguides, and for example, can connect waveguides and optical fibers of a photonic integrated circuit (PIC). Considering that the outer diameter of the optical fiber may be about 125 μm, the spacing between two adjacent optical fibers can be at least 127 μm. On the other hand, the distance between adjacent waveguides in a PIC can be about 2 μm to about 3 μm. Furthermore, the mode size of the light propagating along the optical fiber (i.e., the size of the area in the cross section of the optical fiber where the light is distributed) can be about 10 μm in diameter, while the mode size in the PIC can be about 0.2 μm × 0.5 μm. As mentioned above, it is difficult to combine two waveguides with different environmental conditions using only a structure that can only form a two-dimensional transmission path. The coupling device 100 according to the embodiment can form different types of transmission paths and includes a first waveguide 141 and a second waveguide 142 manufactured in different ways, thereby providing an efficient data transmission structure.

[0065] Furthermore, the coupling device 100 according to the embodiment can also appropriately utilize the second waveguide 142, which has a relatively long manufacturing time, thereby reducing the overall manufacturing time. For example, in the coupling waveguide 140, the length of the first waveguide 141 can be formed as long as possible, while the length of the second waveguide 142 can be relatively shortened. The length of the first waveguide 141 in a first direction (e.g., the X direction) can be about 50% or more of the length of the substrate 110 in the X direction, wherein the first direction can be the direction of the transmission path of the first waveguide 141. Alternatively, the length of the first waveguide 141 in the first direction (e.g., the X direction) can be about 60% or more, or about 70% or more, of the length of the substrate 110 in the X direction. These values ​​are illustrative and not limited thereto. As the length of the first waveguide 141 in the first direction (e.g., the X direction) increases, the length of the second waveguide 142 can be shortened, and the total time required to manufacture the coupling waveguide 140 can be shortened.

[0066] Figure 3 It shows in Figure 1 The electromagnetic field distribution at the positions where the first waveguide and the second waveguide are adjacent to each other in the coupling device is calculated and simulated.

[0067] It can be seen that the difference between the refractive index of the first waveguide 141 and the refractive index of the second waveguide 142 can be approximately 0.0025, and the light transmitted through the first waveguide 141 and the second waveguide 142 can be transmitted to the second waveguide 142 at a position adjacent to the first waveguide 141. When the distance between the first waveguide 141 and the second waveguide 142 is approximately 1 μm, it can be confirmed that approximately 99.67% of the optical power has been transmitted to the other waveguide during a propagation process of approximately 1 mm.

[0068] Figure 4 This is a perspective view showing a schematic structure of the coupling device according to an embodiment. Figure 5Aand Figure 5B They are shown separately Figure 4 Side view of the first and second surfaces of the coupling device.

[0069] Coupling device 101 and Figure 1 The difference between the coupling device 100 shown is that the former also includes a third waveguide 160.

[0070] The third waveguide 160 may extend from the first surface 110a to the second surface 110b and may be a waveguide with a constant distance from the third surface 110c. The third waveguide 160 may comprise the same material as the first waveguide 141. The third waveguide 160 may be manufactured together with the first waveguide 141 during the manufacture of the first waveguide 141. That is, the third waveguide 160 may be positioned from the third surface 110c of the substrate 110 toward the interior of the substrate 110 and may be manufactured by ion implantation at the location in the substrate 110 where the third waveguide 160 is to be formed.

[0071] like Figure 5A As shown, the end of the third waveguide 160 and the first end E1 of the first waveguide 141 of the coupling waveguide 140 can all be arranged in the same row at the first surface 110a of the coupling device 101. In contrast, as... Figure 5B As shown, at the second surface 110b of the coupling device 101, the end of the third waveguide 160 can be arranged in a single row, while the fourth end E4 of the second waveguide 142 of the coupling waveguide 140 is arranged in another single row at a position different from that of the third waveguide 160, so that these ends can be arranged in two rows as a whole.

[0072] Figure 6A and Figure 6B The images show side views of the first and second surfaces of the coupling device according to an embodiment.

[0073] The coupling device 102 in this embodiment and Figure 4 The difference of the coupling device 101 is that, in addition to Figure 4 In addition to the coupling waveguide 140 and the third waveguide 160 provided in the coupling device 101, the coupling device 102 also includes a coupling waveguide 150.

[0074] Coupled waveguide 150 can be similar to coupled waveguide 140, as shown in the reference. Figure 2A As described in detail, the coupling waveguide 150 may include a first waveguide 151 and a second waveguide 152, but the positioning depth of the fourth end E4 of the second waveguide 152 in the substrate 110 may be different from that of the fourth end E4 of the second waveguide 142. That is, the distances of the fourth end E4 of the second waveguide 152 and the fourth end E4 of the second waveguide 142 from the third surface 110c may be different.

[0075] like Figure 6A As shown, the ends of the third waveguide 160, the first end E1 of the first waveguide 141 of the coupling waveguide 140, and the first end E1 of the first waveguide 151 of the coupling waveguide 150 can all be arranged in the same row at the first surface 110a of the coupling device 102. In contrast, as... Figure 6B As shown, at the second surface 110b of the coupling device 102, the end of the third waveguide 160 can be arranged in a single row, the fourth end E4 of the second waveguide 142 of the coupling waveguide 140 can be arranged in a single row at a position different from that of the third waveguide 160, and the fourth end E4 of the second waveguide 152 of the coupling waveguide 150 can be arranged in another single row at a position different from that of the coupling waveguide 140, so that all these ends can be arranged in three rows as a whole.

[0076] In an embodiment, the coupling device may further include a fourth coupling waveguide located at other positions. That is, the ends of the coupling waveguide may be arranged in multiple rows, i.e., three or more rows, at the second surface 110b.

[0077] Figure 7 This is a perspective view showing a schematic structure of the coupling device according to an embodiment. Figure 8 It shows Figure 7 A detailed perspective view of the coupling waveguides installed in the coupling device.

[0078] In the coupling device 103 of this embodiment, the detailed structure of the coupling waveguide 170 can be compared with... Figure 1 The coupled waveguide 140 is different.

[0079] The coupling waveguide 170 provided in the coupling device 103 may include a first waveguide 171 and a second waveguide 172, and may also include a directional coupler 173 arranged between the first waveguide 171 and the second waveguide 172.

[0080] Similar to the first waveguide 141 described above, the first waveguide 171 may include a first end E1 and a second end E2, and may form a transmission path parallel to the third surface 110c of the substrate 110.

[0081] The directional coupler 173 may be arranged adjacent to and parallel to the first waveguide 171. The directional coupler 173 may comprise the same material as the first waveguide 171. The directional coupler 173 may be formed together with the first waveguide 171 using the same process during its fabrication. When viewed from a second direction (e.g., the Y direction), the directional coupler 173 may be arranged to overlap with the first waveguide 171. The second direction may be parallel to the third surface 110c of the substrate 110 and perpendicular to the first direction (e.g., the X direction), where the first direction may be the direction of the transmission path of the first waveguide 171. The overlap length between the directional coupler 173 and the first waveguide 171 may be an overlap length d1. The spacing between the directional coupler 173 and the first waveguide 171 may be a distance d2. The overlap length d1 and the distance d2 may be configured such that light propagating along the first waveguide 171 can be transmitted to the directional coupler 173. For example, the overlap length d1 can be approximately 0.1 mm to 5 mm, and the distance d2 can be approximately 3 μm or less.

[0082] The directional coupler 173 can be arranged adjacent to the second waveguide 172. Similar to the second waveguide 142 described above, the second waveguide 172 can include a third end E3 and a fourth end E4 at different depths within the substrate 110. One end of the directional coupler 173 can contact the third end E3. The second waveguide 172 can form a transmission path with a gradually increasing distance from the third surface 110c.

[0083] The coupling device of the embodiment may include Figure 7 The coupled waveguide 170 shown and Figure 1 The coupled waveguide 140 is shown.

[0084] The coupling device of the embodiment may include Figure 4 The planar third waveguide 160 shown and Figure 7 The coupled waveguide 170 is shown.

[0085] The coupling device of the embodiment may include having Figure 7 The coupled waveguide 170 of the structure shown can have two or more types of depth positions of the fourth end E4 in the substrate 110.

[0086] Figure 9 This is a detailed perspective view showing the coupling waveguide arranged in the coupling device according to an embodiment.

[0087] In this embodiment, the coupling waveguide 240 and the coupling device are provided with Figure 2A The difference in the coupled waveguide 140 shown is the relative positional relationship between the first waveguide 241 and the second waveguide 242.

[0088] The second waveguide 242 can be arranged below the first waveguide 241, that is, on the substrate (e.g., Figure 1 The third end E3 is located deeper than the first waveguide 241 in the substrate 110. The height position of the third end E3 may be different from the height position of the second end E2; in other words, the third end E3 and the second end E2 are located at a distance from the third surface (e.g., Figure 1 The distance to the third surface 110c can be different.

[0089] The first waveguide 241 and the second waveguide 242 can be arranged such that some regions of them overlap when viewed from the Z direction. In this arrangement, coupling between the first waveguide 241 and the second waveguide 242 can occur in the Z direction.

[0090] For the materials or shapes of the first waveguide 241 and the second waveguide 242, as well as the spacing or overlap length between the first waveguide 241 and the second waveguide 242, please refer to the remaining description of the first waveguide 141 and the second waveguide 142 above.

[0091] The coupling waveguide 240 can be applied to the coupling devices 100, 101, 102 and 103 described above. For example, it can replace or be provided together with the coupling waveguides 140, 150 and 170.

[0092] Figure 10 This is a flowchart illustrating a method for manufacturing a coupling device according to an embodiment.

[0093] A method of manufacturing a coupling device may include: forming a first waveguide in a substrate having a transmission path at a constant distance from the surface of the substrate; and forming a second waveguide in the substrate having a transmission path at a non-constant distance from the surface of the substrate.

[0094] The first waveguide can be fabricated using ion implantation, while the second waveguide can be fabricated using laser beam irradiation. The first and second waveguides fabricated as described above can have the shapes described above.

[0095] The method for manufacturing the coupling device is described below.

[0096] First, a substrate can be prepared (operation S10). The substrate 110 may include a glass material, or it may include various other transparent plastic materials.

[0097] The substrate can be made into a rectangular block, but is not limited to this. Shapes such as... can be pre-formed on the substrate. Figure 1 The described guide pin hole.

[0098] Next, alignment marks can be formed on the substrate (e.g., within the substrate) (operation S15), and a plurality of first waveguides can be formed within the substrate by photolithography (operation S20). Operation S15, forming the alignment marks, and operation S20, forming the first waveguides can be performed together in the same process. For example, a mask with a pattern suitable for the shape and number of alignment marks and first waveguides can be arranged on the substrate, and ions can be implanted into the substrate. Accordingly, the refractive index of the substrate at the ion implantation site can be changed, thereby forming the alignment marks and the first waveguides.

[0099] Next, multiple second waveguides can be formed using a writing method (operation S25). For example, a method can be used to focus a high-power pulsed laser at the location within the substrate where the second waveguide is to be formed. The strong energy focused at a predetermined location within the substrate can melt the substrate material at that location, and the refractive index can be increased. By changing the focus position, a second waveguide capable of having a three-dimensional transmission path can be formed.

[0100] The order of operations S20 for forming the first waveguide and S25 for forming the second waveguide can be interchanged. In this case, operation S15 for forming the alignment mark can be performed beforehand, or it can be performed together with operation S25 for forming the second waveguide.

[0101] The method of forming the first waveguide using photolithography may be limited to creating a planar transmission path in the surface, but the manufacturing speed can be very fast. Forming the second waveguide using writing can be achieved in three dimensions in various forms, but the process time can be very long.

[0102] The coupling device according to the embodiment has a structure in which manufacturing processes with longer processing times and manufacturing processes with shorter processing times can be effectively allocated, thereby achieving efficient manufacturing in terms of time and cost.

[0103] For example, when the coupling device is constructed using photolithography to include only 50 planar first waveguides, the manufacturing time can be as short as 2 minutes. However, the number of optical fibers that can be coupled to the coupling device may be limited to 50.

[0104] Meanwhile, when a coupling device with 100 second waveguides for connection to 100 optical fibers is manufactured by writing, the time required may be approximately 2.6 to 26 hours.

[0105] By using a hybrid photolithography and writing method, the coupling device according to the embodiment can manufacture 100 coupled waveguides that can be connected to 100 optical fibers in about 0.3 hours to 2.6 hours.

[0106] The specific time values ​​are for illustrative purposes only, and the embodiments are not limited to the times shown.

[0107] The coupling device manufactured as described above can be one of the above-described coupling devices 100, 101, 102 and 103, or it can be a coupling device improved therefrom.

[0108] Figure 11 This is a block diagram schematically illustrating an electronic device according to an embodiment.

[0109] Electronic device 1000 may include coupling device 1200 and fiber array 1500 and photonic integrated circuit 1600 respectively connected to the opposite side of coupling device 1200.

[0110] The coupling device 1200 may include any one of the coupling devices 100, 101, 102 and 103 described above, or a coupling device having a combination thereof or an improved structure thereof. That is, the ends of the first waveguide manufactured by photolithography may be arranged in a single row at one end of the coupling device 1200, while the ends of the second waveguide manufactured by writing may be arranged in multiple rows at the other end of the coupling device 1200.

[0111] The fiber array 1500 may include multiple optical fibers, and its output terminals may be coupled to ends arranged in multiple rows at one end of the coupling device 1200.

[0112] The photonic integrated circuit 1600 may include a plurality of photoelectric conversion elements for converting light into electrical signals, and may include planar waveguides for transmitting light transmitted through the coupling device 1200 to each of the plurality of photoelectric conversion elements. These planar waveguides may be coupled to a first planar waveguide arranged in a row in the coupling device 1200.

[0113] Electronic device 1000 can be used for communication between memory, communication between XPU (here, XPU refers to, for example, central processing unit (CPU), graphics processing unit (GPU) etc.) and memory, and data transfer between XPUs.

[0114] Figure 12 An electronic device according to an embodiment is illustrated schematically.

[0115] Electronic device 1001 may be a processor unit package. Electronic device 1001 may include a circuit board 1100, a photonic integrated circuit 1600 formed on the circuit board 1100, a coupling device 1200, a driving circuit EIC 1700 for driving the photonic integrated circuit 1600, a processor 1800, and a memory 1900. The memory 1900 may be a high-bandwidth memory (HBM). Furthermore, electronic device 1001 may also include input interfaces, output interfaces, etc.

[0116] The coupling device 1200 may include multiple coupling waveguides 1210. One end 1200a of the coupling device 1200 may be connected to the photonic integrated circuit 1600, and the other end 1200b may be connected to the fiber array 1500. The fiber array 1500 may include multiple optical fibers 1510, and the output terminals of the multiple optical fibers 1510 may be arranged two-dimensionally in multiple rows with different positions along the Z direction on a plane parallel to the YZ plane. The two-dimensionally arranged output terminals, as described above, may be coupled to the corresponding two-dimensionally arranged ends of the coupling waveguides 1210. The fiber array 1500 may also include guide pins 1530 for coupling with guide pin holes 190 of the coupling device 1200.

[0117] In this manner, light input from the fiber array 1500 to the coupling device 1200 can pass through the coupling waveguide 1210 and be transmitted to multiple planar waveguides disposed in the photonic integrated circuit 1600, thereby incident on the photoelectric conversion element. The light can be converted into an electrical signal by the photoelectric conversion element.

[0118] The above-described coupling device, method of manufacturing the coupling device, and electronic device including the coupling device are described with reference to the non-limiting example embodiments shown in the accompanying drawings.

[0119] The above-mentioned coupling device can optically couple different types of waveguides.

[0120] The coupling waveguides provided in the above-mentioned coupling device may include a first waveguide and a second waveguide manufactured in different ways, and the increase in manufacturing time can be minimized while improving the integration of the coupling waveguides.

[0121] It should be understood that the embodiments described herein should be considered in a descriptive sense and not for limiting purposes only. The description of features or aspects in each embodiment of this disclosure should generally be considered as other similar features or aspects that can be used in other embodiments of this disclosure. Although exemplary embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of this disclosure.

Claims

1. A coupling device, comprising: A substrate includes a first surface, a second surface, and a third surface, wherein the first surface and the second surface face away from each other, and the third surface is located between and connected to the first surface and the second surface; and At least one coupled waveguide extends within the substrate from the first surface to the second surface. Wherein, the at least one coupled waveguide includes a first coupled waveguide, the first coupled waveguide comprising: A first waveguide, located on the third surface of the substrate, includes a first end and a second end, wherein the first end is exposed on the first surface, the second end is inside the substrate, and the first waveguide further includes a transmission path from the first end to the second end in a first direction parallel to the third surface; and The second waveguide includes a third end and a fourth end, wherein the third end is adjacent to the first waveguide within the substrate, the fourth end is exposed on the second surface, and the distance from the third surface to the third end is different from the distance from the third surface to the fourth end.

2. The coupling device according to claim 1, wherein, The refractive index of the first waveguide is different from that of the second waveguide.

3. The coupling device according to claim 2, wherein, The difference between the refractive index of the first waveguide and the refractive index of the second waveguide is 0.003 or less.

4. The coupling device according to claim 1, wherein, The third end of the second waveguide is adjacent to the first waveguide, such that light propagating through the second waveguide is transmitted to the first waveguide.

5. The coupling device according to claim 1, wherein, A portion of the first waveguide and a portion of the second waveguide overlap each other in the substrate in a second direction that is parallel to the third surface and perpendicular to the first direction.

6. The coupling device according to claim 5, wherein, The distance between a portion of the first waveguide and a portion of the second waveguide in the second direction is 3 μm or less.

7. The coupling device according to claim 5, wherein, The overlap length between a portion of the first waveguide and a portion of the second waveguide is 0.1 mm to 5 mm.

8. The coupling device according to claim 1, wherein, A portion of the first waveguide and a portion of the second waveguide overlap each other in the substrate in a third direction perpendicular to the third surface.

9. The coupling device according to claim 1, wherein, The length of the first waveguide in the first direction is 50% or more of the length of the substrate in the first direction.

10. The coupling device according to claim 1, wherein, The first coupling waveguide also includes a directional coupler between the first waveguide and the second waveguide. The directional coupler extends parallel to the first waveguide, and the material of the directional coupler is the same as that of the first waveguide.

11. The coupling device according to claim 10, wherein, One end of the directional coupler is in contact with the third end.

12. The coupling device according to claim 1, wherein, The first waveguide is formed by implanting ions into the material of the substrate.

13. The coupling device according to claim 12, wherein, The second waveguide is formed by modifying the material of the substrate using a laser.

14. The coupling device according to claim 1, wherein, The at least one coupling waveguide further includes a second coupling waveguide, the second coupling waveguide comprising: A third waveguide, located on the third surface of the substrate, includes a fifth end and a sixth end, wherein the fifth end is exposed on the first surface, the sixth end is located inside the substrate, and the third waveguide further includes a transmission path in the first direction from the fifth end to the sixth end; and A fourth waveguide includes a seventh end and an eighth end, wherein the seventh end is adjacent to the third waveguide within the substrate, the eighth end is exposed on the second surface, and the distance from the third surface to the seventh end is different from the distance from the third surface to the eighth end. The distance from the third surface to the eighth end is different from the distance from the third surface to the fourth end.

15. The coupling device of claim 1, further comprising a third waveguide extending from the first surface to the second surface, the distance between the third waveguide and the third surface being constant. in, The material of the third waveguide is the same as that of the first waveguide.

16. The coupling device of claim 1, further comprising alignment marks in the third surface of the substrate.

17. The coupling device of claim 1, further comprising a guide pin hole in the substrate and passing through an opening on the second surface of the substrate.

18. A method of manufacturing a coupling device, the method comprising: A first waveguide is formed within a substrate, the first waveguide including a first transmission path, wherein the distance from the surface of the substrate to the first transmission path is constant; and A second waveguide is formed within the substrate, the second waveguide including a second transmission path, wherein the distance from the surface of the substrate to the second transmission path is not constant.

19. The method according to claim 18, wherein, Forming the first waveguide includes ion implantation, and forming the second waveguide includes laser beam irradiation.

20. An electronic device, comprising: Coupling device; An optical fiber array is connected to the first end of the coupling device; as well as A photonic integrated circuit is connected to the second end of the coupling device. The coupling device includes: A substrate includes a first surface, a second surface, and a third surface, wherein the first surface and the second surface face away from each other, and the third surface is located between and connected to the first surface and the second surface; and A coupling waveguide extends within the substrate from the first surface to the second surface. The coupled waveguide includes: A first waveguide, in the third surface, includes a first end and a second end, wherein the first end is exposed on the first surface, the second end is inside the substrate, and the first waveguide further includes a transmission path from the first end to the second end in a first direction parallel to the third surface; and The second waveguide includes a third end and a fourth end, wherein the third end is adjacent to the first waveguide within the substrate, the fourth end is exposed on the second surface, and the distance from the third surface to the third end is different from the distance from the third surface to the fourth end.

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