Photoelectric hybrid substrate

Abstract

This photoelectric hybrid substrate has: a first glass substrate having a first electric wiring section including one or a plurality of through-vias in which a conductor is installed; and a second glass substrate having an optical waveguide section including a core portion, wherein the first glass substrate and the second glass substrate are joined together and integrated with each other.

Description

Optoelectronic mixed board

[0001] The present invention relates to an optoelectronic hybrid board.

[0002] As information processing devices have become faster in recent years, attention has been focused on optoelectronic hybrid technology, which converts electrical signals output from a semiconductor device into optical signals and transmits the converted optical signals to other semiconductor devices and optical receivers through optical wiring formed on the same substrate.

[0003] Furthermore, in order to further reduce the size and improve the performance of semiconductor components, high-performance semiconductor packaging technology that stacks various chips three-dimensionally is attracting attention. Typically, such packaging technology also utilizes a glass package substrate with TGVs (Through Glass Vias) formed therein.

[0004] US Patent Application Publication No. 2023 / 0086881

[0005] Generally, in an optoelectronic hybrid board, an optical waveguide is provided on the board. However, if one glass substrate is used for both the optical waveguide and the package substrate, various processes must be performed on the single glass substrate, such as through-hole processing, metal filling of the through-holes, optical waveguide formation, and / or conductive layer patterning.

[0006] However, this manufacturing method requires many steps to complete the product, and if a defect occurs during the process, the work in progress must be discarded and the product must be remanufactured from the beginning, which also increases the manufacturing cost of the optoelectronic hybrid board.

[0007] The present invention has been made in consideration of the above background, and aims to provide an optoelectronic hybrid board having a configuration that can significantly reduce the need for discarding and remanufacturing work-in-progress during production.

[0008] The present invention provides an optoelectronic hybrid substrate comprising: a first glass substrate having a first electrical wiring section including one or more through vias in which a conductor is installed; and a second glass substrate having an optical waveguide section including a core portion, wherein the first glass substrate and the second glass substrate are bonded to each other and integrated.

[0009] The present invention can provide an optoelectronic hybrid board having a configuration that can significantly reduce the need for discarding and remanufacturing work-in-progress during manufacturing.

[0010] 1 is a perspective view schematically showing an example of the configuration of an optoelectronic hybrid substrate according to an embodiment of the present invention. FIG. 1 is a diagram schematically showing a cross section taken along line II of the optoelectronic hybrid substrate according to an embodiment of the present invention shown in FIG. 2. FIG. 2 is a cross-sectional view schematically showing a modified example of the optoelectronic hybrid substrate according to an embodiment of the present invention shown in FIG. 3. FIG. 3 is a cross-sectional view schematically showing the configuration of an optoelectronic hybrid substrate according to another embodiment of the present invention. FIG. 4 is a diagram schematically showing a cross section taken along line II-II of the first glass substrate shown in FIG. 4. FIG. 5 is a diagram schematically showing a cross section of a second glass substrate included in an optoelectronic hybrid substrate according to an embodiment of the present invention. FIG. 6 is a diagram schematically showing a cross section taken along line III-III of the second glass substrate shown in FIG. 6. FIG. 7 is a diagram schematically showing a cross section of a second glass substrate used in a modified example of the optoelectronic hybrid substrate shown in FIG. 2-1 above. FIG. 8 is a cross-sectional view schematically showing an example of a semiconductor package including an optoelectronic hybrid substrate according to an embodiment of the present invention. FIG. 9 is a cross-sectional view schematically showing a modified example of the semiconductor package according to an embodiment of the present invention shown in FIG. FIG. 2 is a flow chart schematically illustrating an example of a method for manufacturing an optoelectronic hybrid substrate according to an embodiment of the present invention.

[0011] An embodiment of the present invention will be described below.

[0012] In one embodiment of the present invention, there is provided an optoelectronic hybrid substrate comprising: a first glass substrate having a first electrical wiring section including one or more through vias in which a conductor is installed; and a second glass substrate having an optical waveguide section including a core portion, wherein the first glass substrate and the second glass substrate are bonded to each other and integrated.

[0013] As mentioned above, when an optoelectronic hybrid board is manufactured through various processes using a single glass substrate, the number of processes required to complete the product increases, and if a defect occurs during the process, the work in progress must be discarded and the product must be remanufactured, which also increases the manufacturing cost of the optoelectronic hybrid board.

[0014] In contrast, in one embodiment of the present invention, an optoelectronic hybrid substrate is constructed by bonding and integrating a first glass substrate having at least one electrical wiring section and a second glass substrate having at least one optical waveguide section.

[0015] In this application, the term "electrical wiring section" refers to an electrical wiring section in a glass substrate that includes one or more through vias with a conductor installed therein, and the term "optical waveguide section" refers to a light-guiding section in a glass substrate that has a core portion formed therein and on the surface thereof that allows light to propagate.

[0016] In one embodiment of the present invention, if a defect occurs in one of the first and second glass substrates during manufacturing, only that glass substrate can be discarded and remanufactured, eliminating the need to remanufacture the product from scratch. Therefore, in one embodiment of the present invention, it is possible to provide an optoelectronic hybrid substrate more efficiently and at low cost.

[0017] Furthermore, this configuration allows for the free combination of a first glass substrate having various electrical wiring sections and a second glass substrate having various optical waveguide sections, making it possible to more easily manufacture an optoelectronic hybrid substrate having more complex electrical wiring structures and optical waveguide structures, which was previously difficult to manufacture using a conventional manufacturing process based on a single glass substrate.

[0018] In the following description, the first glass substrate will be described as a member for providing a conductive path such as an electrical wiring in the optoelectronic hybrid substrate, and the second glass substrate will be described as a member for providing an optical waveguide such as an optical wiring in the optoelectronic hybrid substrate.

[0019] However, this distinction is merely for the sake of convenience, and the optoelectronic hybrid board according to an embodiment of the present invention also includes an embodiment in which the first glass substrate has an optical waveguide as well as a conductive path, and similarly, the optoelectronic hybrid board according to an embodiment of the present invention also includes an embodiment in which the second glass substrate has an optical waveguide as well as a conductive path.

[0020] (Optoelectronic Hybrid Board According to One Embodiment of the Present Invention) Hereinafter, an optoelectronic hybrid board according to one embodiment of the present invention will be described in more detail with reference to the drawings.

[0021] FIG. 1 is a perspective view schematically showing an example of the configuration of an optoelectronic hybrid board according to an embodiment of the present invention.

[0022] As shown in FIG. 1, an optoelectronic hybrid board 100 according to one embodiment of the present invention (hereinafter referred to as a "first optoelectronic hybrid board") has a configuration having a substantially rectangular lower surface 102 and an upper surface 104 facing each other.

[0023] A recess 108 defined by a sidewall 106 and a bottom surface 107 is formed on the top surface 104 of the first optoelectronic hybrid substrate 100 .

[0024] The first optoelectronic hybrid substrate 100 is constructed by bonding and integrating a first glass substrate 210 and a second glass substrate 310 .

[0025] 1 , the second glass substrate 310 is laminated on top of the first glass substrate 210, and the two are bonded together. Therefore, the lower surface 102 of the first optoelectronic hybrid substrate 100 corresponds to the lower surface of the first glass substrate 210 (a first surface 212 described below), and the upper surface 104 of the first optoelectronic hybrid substrate 100 corresponds to the upper surface of the second glass substrate 310 (a fourth surface 314 described below).

[0026] Although not clear from Fig. 1 , the lower first glass substrate 210 has an electrical wiring section including one or more TGVs (Through Glass Vias) and serves to provide a conductive path. On the other hand, the second glass substrate 310 has an optical waveguide section having at least one core portion and serves to provide a light guide path. In Fig. 1 , the portions (two locations) indicated by dashed lines correspond to the optical waveguide section 340.

[0027] FIG. 2 is a schematic cross-sectional view of the first optoelectronic hybrid board 100 shown in FIG. 1 taken along line II.

[0028] 2, the first glass substrate 210 has a first surface 212 and a second surface 214 facing each other. Similarly, the second glass substrate 310 has a third surface 312 and a fourth surface 314 facing each other.

[0029] The first optoelectronic hybrid substrate 100 is constructed by bonding the second surface 214 of the first glass substrate 210 and the third surface 312 of the second glass substrate 310 to each other.

[0030] The method for bonding the first glass substrate 210 and the second glass substrate 310 is not particularly limited, and the two may be bonded to each other by, for example, surface activated bonding, atomic diffusion bonding, etc. Alternatively, the first glass substrate 210 and the second glass substrate 310 may be bonded to each other via an adhesive.

[0031] The second glass substrate 310 has a through portion 333 that penetrates from the third surface 312 to the fourth surface 314. Therefore, the recess 108 of the first optoelectronic hybrid substrate 100 corresponds to the through portion 333 of the second glass substrate 310, and the sidewall 106 and the bottom surface 107 of the recess 108 correspond to the sidewall of the through portion 333 of the second glass substrate 310 and the second surface 214 of the first glass substrate 210, respectively.

[0032] The first glass substrate 210 has an electrical wiring compartment 240 containing one or more TGVs 230. Electrical conductors 235 are provided on the sidewalls of each TGV 230. Alternatively, as shown in FIG. 2, the electrical conductors 235 may be arranged to fill the interior of each TGV 230.

[0033] 2 , the first glass substrate 210 has one electrical wiring section 240. The electrical wiring section 240 is disposed at a position corresponding to the recess 108 of the first optoelectronic hybrid substrate 100, i.e., approximately in the center of the first glass substrate 210. Therefore, in this example, the electrical wiring section 240 can be seen through the through portion 333 of the second glass substrate 310 in a top view.

[0034] However, it should be noted that the positions and number of the electrical wiring sections 240 installed on the first glass substrate 210 are not particularly limited.

[0035] Typically, within the electrical wiring compartment 240, a conductive material is disposed on the first surface 212 and / or the second surface 214 of the first glass substrate 210, which is connected to the conductors 235 within a given TGV 230. For example, in the example shown in Figure 2, a first pattern 242 of conductive material is disposed on the second surface 214 of the first glass substrate 210.

[0036] Additionally or alternatively, a pattern of conductive material may be formed on the side of first surface 212 within electrical wiring compartment 240 .

[0037] Referring again to FIG. 2, the second glass substrate 310 has an optical waveguide section 340 that includes a core 320 for the optical waveguide.

[0038] 2, the optical waveguide sections 340 are arranged in two locations. Specifically, the optical waveguide sections 340 are arranged on both sides of the through portion 333 of the second glass substrate 310.

[0039] In each optical waveguide section 340 , the core portion 320 is disposed inside the second glass substrate 310 .

[0040] The core portion 320 has a refractive index significantly higher than that of the bulk portion of the second glass substrate 310. Therefore, light introduced from the outside into the optical waveguide section 340 of the first optoelectronic hybrid substrate 100 is confined in the core portion 320 and can propagate along the core portion 320 in a predetermined direction.

[0041] 2 , the core portion 320 of each optical waveguide section 340 extends from one end face of the second glass substrate 310 to one side wall of the through portion 333. That is, both ends of the core portion 320 are open to the outside of the first optoelectronic hybrid substrate 100. This allows an external optical member to be optically connected to the core portion 320 of each optical waveguide section 340.

[0042] However, it should be noted that the positions and number of the optical waveguide sections 340 provided on the second glass substrate 310 are not particularly limited.

[0043] The first optoelectronic hybrid substrate 100 is constructed by laminating a second glass substrate 310 on a first glass substrate 210 and bonding the two together.

[0044] In this configuration, if a defect occurs in either the first glass substrate 210 or the second glass substrate 310 during the manufacturing process, only that glass substrate can be discarded and remanufactured, eliminating the need to remanufacture the entire work-in-progress. Therefore, the first optoelectronic hybrid substrate 100 can be provided more efficiently and at lower cost.

[0045] Furthermore, the first optoelectronic hybrid substrate 100 having such characteristics makes it possible to manufacture more complex electrical wiring structures and optical waveguide structures that are difficult to manufacture from a single glass substrate.

[0046] 2, a second pattern 243 of conductive material formed on the second surface 214 of the first glass substrate 210 is disposed below one (left) optical waveguide section 340 of the second glass substrate 310. Thus, in FIG. 2, the second pattern 243 of conductive material extending in the X direction "intersects" with the core portion 320 extending in the Y direction.

[0047] Such a structure in which the core portion 320 and the second pattern 243 of conductive material intersect is not easy to manufacture from a single glass substrate. However, since the first optoelectronic hybrid substrate 100 is configured by bonding and integrating the first glass substrate 210 and the second glass substrate 310, such a "multi-level intersection" structure can be constructed relatively easily.

[0048] FIG. 2A is a schematic diagram showing a cross section of a modified example of the optoelectronic hybrid board according to the embodiment of the present invention shown in FIG.

[0049] The optoelectronic hybrid substrate 100-1 shown in Fig. 2-1 has a configuration basically similar to that of the first optoelectronic hybrid substrate 100 shown in Fig. 2. However, this optoelectronic hybrid substrate 100-1 differs from the first optoelectronic hybrid substrate 100 in the configuration of the second glass substrate 310. That is, in the optoelectronic hybrid substrate 100-1, the second glass substrate 310 has an optical waveguide section 340-1. Furthermore, the optical waveguide section 340-1 has a configuration in which a core section 320-1 is sandwiched between an overclad section 321 and an underclad section 322. The core section 320-1 has an area that is not covered by the overclad section 321.

[0050] The optical waveguide section 340-1 may have such a configuration.

[0051] (Optoelectronic Hybrid Board According to Another Embodiment of the Present Invention) Next, with reference to FIG. 3, an optoelectronic hybrid board according to another embodiment of the present invention will be described.

[0052] FIG. 3 is a cross-sectional view schematically showing the configuration of an optoelectronic hybrid board according to another embodiment of the present invention.

[0053] 3, an optoelectronic hybrid board 500 according to another embodiment of the present invention (hereinafter referred to as the "second optoelectronic hybrid board") has a configuration similar to that of the above-described first optoelectronic hybrid board 100. Therefore, in the second optoelectronic hybrid board 500, parts similar to those of the first optoelectronic hybrid board 100 are designated by reference numerals that are 400 larger than the reference numerals shown in FIGS.

[0054] For example, the second optoelectronic hybrid board 500 has a first glass substrate 610 having a first electrical wiring section 640 approximately in the center, and a second glass substrate 710 having two optical waveguide sections 740 sandwiched between them by a through portion 733.

[0055] Additionally, the first electrical wiring section 640 of the first glass substrate 610 includes one or more first TGVs 630 filled with a first conductor 635 and a first pattern 642 of conductive material disposed on the second surface 614 of the first glass substrate 610. Additionally, each optical waveguide section 740 of the second glass substrate 710 includes a core portion 720 formed therein.

[0056] The second optoelectronic hybrid substrate 500 is constructed by laminating a second glass substrate 710 on top of a first glass substrate 610 and bonding the two together.

[0057] However, unlike the first optoelectronic hybrid board 100, the second optoelectronic hybrid board 500 further includes a second electrical wiring section 650 configured within the first glass substrate 610. The second electrical wiring section 650 is disposed below the left optical waveguide section 740.

[0058] The second electrical wiring section 650 has a plurality of second TGVs 660, each of which has a second conductor 665 filled or disposed therein. The second electrical wiring section 650 also has a second pattern 643 of conductive material disposed on the second surface 614 of the first glass substrate 610. The second pattern 643 of conductive material is electrically connected to the second conductor 665 in a given second TGV 660.

[0059] In the second optoelectronic hybrid board 500, the core portion 720 in the left optical waveguide section 740 and the second pattern 643 of conductive material in the second electrical wiring section 650 below it also form a "multi-level intersection."

[0060] Such a "multi-level crossing" structure is not easy to manufacture using conventional methods. However, in one embodiment of the present invention, the second optoelectronic hybrid substrate 500 having such a complex structure can be constructed relatively easily.

[0061] (Details of Each Component) Next, each component constituting the optoelectronic hybrid board according to one embodiment of the present invention will be described in more detail. Note that the components will be described here using the first optoelectronic hybrid board 100 described above as an example. Therefore, when representing each component of the optoelectronic hybrid board, the reference symbols shown in FIGS. 1 and 2 will be used.

[0062] (First Glass Substrate 210) The first glass substrate 210 serves to provide a predetermined conductive circuit for the first optoelectronic hybrid substrate 100. To this end, the first glass substrate 210 is provided with at least one electrical wiring section 240 at a predetermined position.

[0063] The first glass substrate 210 may have any composition as long as it is "glass."

[0064] In this application, the term "glass" refers not only to amorphous glass but also to glass ceramics, which are composites of glass and crystal. In the embodiments of the present invention, the ratio of the crystalline phase to the amorphous phase in the glass ceramic is not particularly limited, and any glass ceramic containing both a crystalline phase and an amorphous phase is considered to be a glass ceramic.

[0065] Furthermore, the size and shape of the first glass substrate 210 are not particularly limited and can be selected based on desired design specifications.

[0066] Fig. 4 shows a schematic perspective view of the first glass substrate 210. Fig. 5 shows a schematic cross section of the first glass substrate 210 taken along line II-II of Fig. 4.

[0067] As shown in FIGS. 4 and 5, a first glass substrate 210 has a first surface 212 and a second surface 214 facing each other.

[0068] The first glass substrate 210 also has an electrical wiring section 240 in the approximate center, and a plurality of TGVs 230 are formed in the electrical wiring section 240. The TGVs 230 penetrate from the first surface 212 to the second surface 214, and are filled with conductors 235. However, the conductors 235 may be arranged to cover the sidewalls of the TGVs 230 rather than filling the entire TGVs 230.

[0069] The number and dimensions (for example, diameter and pitch) of the TGVs 230 are not particularly limited.

[0070] There is no particular limitation on the type of the conductor 235. The conductor 235 may be, for example, copper.

[0071] Typically, the first surface 212 and / or second surface 214 of the first glass substrate 210 has disposed thereon a pattern of conductive material (not shown in FIGS. 4 and 5 ) that is electrically connected to the conductors 235 in the TGV 230.

[0072] 4 and 5 are merely examples, and the electrical wiring section 240 may be disposed at any position within the first glass substrate 210. Furthermore, a plurality of electrical wiring sections 240 may be formed.

[0073] (Second Glass Substrate 310) The second glass substrate 310 serves to provide a predetermined light guide circuit for the first optoelectronic hybrid substrate 100. To this end, the second glass substrate 310 is provided with at least one optical waveguide section 340.

[0074] The second glass substrate 310 may have any composition as long as it is “glass.” The composition of the second glass substrate 310 may be the same as or different from the composition of the first glass substrate 210.

[0075] The size and shape of the second glass substrate 310 are not particularly limited and can be selected based on desired design specifications.

[0076] Fig. 6 is a schematic perspective view of the second glass substrate 310. Fig. 7 is a schematic cross-sectional view of the second glass substrate 310 taken along line III-III of Fig. 6.

[0077] As shown in FIGS. 6 and 7, the second glass substrate 310 has a through portion 333 at approximately the center, and optical waveguide sections 340 are arranged on both sides of the through portion 333 .

[0078] In each optical waveguide section 340, a core portion 320 is arranged along a predetermined direction (for example, the Y direction in FIGS. 6 and 7).

[0079] In a typical case, the core 320 is disposed in the optical waveguide section 340 with both ends open to the outside. For example, in the examples shown in Figures 6 and 7, the core 320 is disposed so that one end corresponds to the end face of the second glass substrate 310 and the other end corresponds to the side wall of the through portion 333.

[0080] This allows the light guide member to be optically connected to the core portion 320 of the optical waveguide section 340 when a light guide member or the like is installed externally on the first optoelectronic hybrid substrate 100 .

[0081] The core portion 320 has a refractive index higher than that of the bulk of the second glass substrate 310. For example, the refractive index of the core portion 320 may be 1.003 to 1.1 times higher than that of the bulk of the second glass substrate 310.

[0082] 6 and 7 are merely examples, and the optical waveguide sections 340 and the core sections 320 may be disposed at any positions within the second glass substrate 310. Furthermore, the number of optical waveguide sections 340 is not particularly limited, and the number of optical waveguide sections 340 may be one, or three or more.

[0083] 7-1 is a schematic cross-sectional view of the second glass substrate 310 used in the modified example 100-1 of the optoelectronic hybrid substrate shown in FIG. 2-1. As shown in FIG. 7-1, in this example, the second glass substrate 310 has an optical waveguide section 340-1, which has an overclad section 321, a core section 320-1, and an underclad section 322. An area not covered by the overclad section 321 exists above the core section 320-1.

[0084] The optical waveguide section 340-1 and the core portion 320-1 may be disposed at any position within the second glass substrate 310. Furthermore, the number of optical waveguide sections 340-1 is not particularly limited, and the number of optical waveguide sections 340-1 may be one, or three or more.

[0085] (Application Example of Optoelectronic Hybrid Board According to One Embodiment of the Present Invention) Next, with reference to FIG. 8, an application example of the optoelectronic hybrid board according to one embodiment of the present invention will be described.

[0086] 8 is a cross-sectional view showing a semiconductor package including an optoelectronic hybrid substrate according to an embodiment of the present invention. Here, the description will be given taking as an example a case where the first optoelectronic hybrid substrate 100 having the above-described configuration is used as the optoelectronic hybrid substrate according to an embodiment of the present invention.

[0087] As shown in FIG. 8, this semiconductor package 1000 includes a first optoelectronic hybrid board 100 and various elements.

[0088] For example, in the example shown in FIG. 8, the semiconductor package 1000 includes a first photonic circuit (PIC) 1200, a second PIC 1201, an ASIC 1210, a first passive device 1230, and a second passive device 1231, and so on.

[0089] In addition, the semiconductor package 1000 has a first metal redistribution layer 1100 on the side of the lower surface 102 of the first optoelectronic hybrid substrate 100, and a second metal redistribution layer 1102 on the bottom surface 107 of the recess 108 of the first optoelectronic hybrid substrate 100.

[0090] The various elements are arranged so as to be electrically connected to the second metal redistribution layer 1102 .

[0091] The first metal redistribution layer 1100 is disposed so as to be electrically connected to the electrical wiring section 240 of the first glass substrate 210. Similarly, the second metal redistribution layer 1102 is disposed on top of the electrical wiring section 240 of the first glass substrate 210 so as to be electrically connected to the electrical wiring section 240.

[0092] As a result, various elements can be electrically connected to other elements arranged at desired positions, regardless of whether they are on the upper or lower side of the first optoelectronic hybrid substrate 100 .

[0093] The first PIC 1200 is also optically connected to the core 320 in one of the optical waveguide sections 340 (on the left side of FIG. 8 ) on the second glass substrate 310. Similarly, the second PIC 1201 is optically connected to the core 320 in another of the optical waveguide sections 340 on the second glass substrate 310 (on the right side of FIG. 8 ).

[0094] Therefore, the first PIC 1200 and the second PIC 1201 can convert light propagating from an external optical component that is optically connected to the first PIC 1200 and the second PIC 1201 into an electrical signal inside the semiconductor package 1000. Furthermore, the obtained electrical signal can be electrically connected to a predetermined electronic device.

[0095] It should be noted that the configuration shown in FIG. 8 is merely an example, and the optoelectronic hybrid board according to one embodiment of the present invention may be applied in any manner to a semiconductor package.

[0096] FIG. 8B shows a modification of the semiconductor package 1000 shown in FIG.

[0097] As shown in Fig. 8-2, this semiconductor package 1000-1 basically has the same configuration as the semiconductor package 1000 shown in Fig. 8. However, this semiconductor package 1000-1 uses the configuration shown in Fig. 7-1 as the second glass substrate 310. That is, in this semiconductor package 1000-1, the optical waveguide section 340-1 has a configuration in which the core 320-1 is sandwiched between the overclad portion 321 and the underclad portion 322.

[0098] The PIC 1200 is optically connected to a core 320-1 included in one optical waveguide section 340-1 (left side of FIG. 8-1) of the second glass substrate 310. A part of the PIC 1200 is disposed in an area not covered by the overclad 321 above the core 320-1.

[0099] Similarly, the PIC 1201 is optically connected to a core 320-1 included in another optical waveguide section 340-1 (on the right side of FIG. 8-1) of the second glass substrate 310. Also, a part of the PIC 1201 is disposed in an area not covered by the overclad section 321 above the core 320-1.

[0100] (Method for Manufacturing an Optoelectronic Hybrid Board According to an Embodiment of the Present Invention) Next, an example of a method for manufacturing an optoelectronic hybrid board according to an embodiment of the present invention will be described with reference to FIG.

[0101] FIG. 9 is a flow chart showing a schematic example of a method for manufacturing an optoelectronic hybrid substrate according to an embodiment of the present invention.

[0102] As shown in FIG. 9 , a method for manufacturing an optoelectronic hybrid substrate according to one embodiment of the present invention (hereinafter referred to as the “first method”) includes: (I) a step (S110) of manufacturing a first glass substrate having an electrical wiring section; (II) a step (S120) of manufacturing a second glass substrate having an optical waveguide section; and (III) a step (S130) of bonding the first glass substrate and the second glass substrate together to form an integrated body.

[0103] Note that steps S110 and S120 may be performed in any order.

[0104] Each step will be described in more detail below. Note that the manufacturing method will be described using the first optoelectronic hybrid substrate 100 as an example. Therefore, the reference symbols shown in FIGS. 1 and 2 will be used to represent the respective members and parts.

[0105] (Step S110) First, a first glass plate for the first glass substrate 210 is prepared.

[0106] The first glass plate may have any composition as long as it is “glass.” Furthermore, the dimensions of the first glass plate are not particularly limited.

[0107] Next, one or more through holes are formed in the first glass sheet at predetermined locations.

[0108] The method for forming the through holes is not particularly limited. The through holes may be formed, for example, by a laser irradiation process or an etching process. The opening diameter of the through holes is not particularly limited, but may be, for example, in the range of 10 μm to 500 μm.

[0109] Thereafter, if necessary, the first glass plate may be subjected to a wet etching process, which allows the dimensions and shape of the through-holes to be closer to the target range.

[0110] A conductive material, such as copper, is then applied to the sidewalls of each through-hole.

[0111] The conductor may be provided on the sidewall of each through-hole by, for example, plating, or may be provided so as to fill each through-hole.

[0112] Thereafter, as needed, a first pattern 242 or the like of conductive material is placed at predetermined locations on the first and / or second surfaces of the first glass sheet.

[0113] However, if a conductor is placed or filled in the through-holes by plating or the like, a conductor layer may also be formed on the first surface and / or the second surface of the first glass plate. In this case, the first pattern 242 of the conductive material may be configured by patterning the conductor layer on the first surface and / or the second surface.

[0114] Through the above steps, the electrical wiring sections 240 are formed at predetermined positions on the first glass plate, and the first glass substrate 210 is manufactured.

[0115] The number of through holes included in one electrical wiring section 240 is not particularly limited, but may be in the range of 100 to 5 million, for example.

[0116] (Step S120) Next, a second glass plate for the second glass substrate 310 is prepared.

[0117] The second glass sheet may have the same or a different composition than the first glass sheet.

[0118] For example, if the composition of the first glass plate is the same as the composition of the second glass plate, the thermal expansion coefficients of the first glass substrate 210 and the second glass substrate 310, which will be subsequently constructed from these glass plates, can be matched. This significantly reduces thermal stress that may occur inside the first optoelectronic hybrid substrate 100 during and after manufacture. On the other hand, if the composition of the second glass plate is different from the composition of the first glass plate, optical height detection using reflection behavior is possible when the first glass substrate 210 and the second glass substrate 310 are later laminated together. This facilitates assembly of the first optoelectronic hybrid substrate 100.

[0119] Next, a through portion 333 is formed at a predetermined position on the second glass plate.

[0120] There are no particular limitations on the method for forming the through-portion 333, and a general method may be used. For example, the through-portion 333 may be formed in the second glass plate by a laser irradiation process, an etching process, or the like.

[0121] Next, the optical waveguide sections 340 (particularly the core portions 320) are formed in predetermined locations on the second glass plate.

[0122] There are no particular limitations on the manufacturing method of the optical waveguide section 340, and various methods may be employed. For example, the optical waveguide section 340 may be manufactured using a laser irradiation method, an ion exchange method, a chemical vapor deposition method, a sputtering method, an etching method, a flame deposition method, or the like.

[0123] Hereinafter, as an example, a method for forming the optical waveguide section 340 by ion exchange (hereinafter referred to as the "second method") will be described.

[0124] The second method is: (i) Na ２ The method includes: (i) a step of preparing a second glass sheet containing O; (ii) a step of ion-exchanging Na ions in the second glass sheet with Ag ions (first ion-exchange step); and (iii) a step of ion-exchanging some of the Ag ions in the ion-exchanged second glass sheet with Na ions again (second ion-exchange step).

[0125] In the first ion exchange step (ii), a first molten salt containing Ag is brought into contact with a predetermined position of the second glass sheet.

[0126] Examples of a method for bringing the first molten salt into contact with the second glass sheet include applying the first molten salt to a predetermined position on the second glass sheet, or immersing the second glass sheet in the first molten salt. The immersion method is particularly preferred because it allows treatment at a high temperature for a long period of time.

[0127] When the second glass plate is immersed in the first molten salt, it is preferable to use a masking material to mask the surface of the second glass plate except for the areas that will become the optical waveguide sections.

[0128] The masking material is selected from materials that do not react with the first molten salt and do not inhibit ion exchange between the second glass sheet and the first molten salt. ２ O ３ , SiO ２ , SiN, TiO ２ Alternatively, it may be made of ITO or the like.

[0129] The composition of the first molten salt is not limited as long as it contains Ag ions. For example, AgNO ３ , Ag ２ SO ４ , Ag ２ CO ３ , and / or AgCl, etc. may be selected. Among them, AgNO ３ The salt containing Ag ions may be used alone or in combination of two or more.

[0130] In order to adjust the Ag ion concentration, it is preferable to use a mixed molten salt, which is a mixture of a salt containing Ag ions and another salt, as the first molten salt.

[0131] Other salts include nitrates, sulfates, carbonates, and chlorides. Of these, nitrates include lithium nitrate, sodium nitrate, potassium nitrate, and cesium nitrate. Sulfates include lithium sulfate, sodium sulfate, potassium sulfate, and cesium sulfate. Carbonates include lithium carbonate, sodium carbonate, and potassium carbonate. Chlorides include lithium chloride, sodium chloride, potassium chloride, and cesium chloride.

[0132] Among these, from the viewpoint of suppressing stress that may be introduced into the glass, the other salt is preferably sodium nitrate, sodium sulfate, sodium carbonate, or sodium chloride, and more preferably sodium nitrate or sodium sulfate. The other salt may be used alone or in combination.

[0133] As a result of the first ion exchange process, the refractive index of the Ag ion-substituted region of the second glass plate (hereinafter referred to as the "first substituted region") increases compared to the bulk portion of the second glass plate, and thus a core portion 320 is formed in the first substituted region.

[0134] A second ion exchange step is then carried out.

[0135] In the second ion exchange process, a portion of the Ag ions on the surface of the first substituted region is again ion-exchanged with Na ions using a second molten salt, thereby forming a second substituted region, which has a lower refractive index than the first substituted region, and therefore can form a low refractive index region in the upper part of the core portion 320.

[0136] This also forms a high refractive index portion, or core portion 320, surrounded by a low refractive index portion including the bulk portion and the second substitution region of the second glass sheet.

[0137] The second molten salt used in the second ion exchange step is not particularly limited as long as it contains Na ions. For example, the second molten salt may be NaNO ３ , Na ２ SO ４ , Na ２ CO ３Among them, NaNO is preferred in terms of melting temperature. ３ and Na ２ SO ４ As the second molten salt, one type may be used, or a plurality of types may be used in combination.

[0138] The second molten salt may be a mixed molten salt obtained by mixing a salt containing Na ions with another salt.

[0139] Other salts include, for example, nitrates, sulfates, carbonates, and chlorides. Nitrates include lithium nitrate, potassium nitrate, and cesium nitrate. Sulfates include lithium sulfate, potassium sulfate, and cesium sulfate. Carbonates include lithium carbonate and potassium carbonate. Chlorides include lithium chloride, potassium chloride, and cesium chloride.

[0140] Among these, from the viewpoint of chemical stability, the other salt preferably includes a nitrate.

[0141] The other salts may be used alone or in combination of two or more kinds.

[0142] By this second method, a second glass substrate 310 having an optical waveguide section 340 is produced.

[0143] The core 320 of the optical waveguide section 340 configured in this manner may have a refractive index distribution therein, for example, the refractive index of the core 320 may be highest at the center and decrease outward.

[0144] Furthermore, the optical waveguide section 340 may have a refractive index distribution in the portion surrounding the core portion 320, where the refractive index is higher below the core portion 320 than above the core portion 320. Alternatively, the optical waveguide section 340 may have a refractive index distribution in the portion surrounding the core portion 320, where the refractive index is higher above the core portion 320 than below the core portion 320.

[0145] It should be apparent to those skilled in the art that the above-described method for manufacturing the second glass substrate 310 is merely an example, and that the optical waveguide section 340 may be manufactured by other methods. For example, when a laser is irradiated so as to be focused inside the second glass plate and scanned in a predetermined direction, the core portion 320 can be formed directly inside the second glass plate.

[0146] Alternatively, a recess may be formed in the second glass plate by an etching process, and a core material may be deposited by, for example, a sputtering method or a CVD method to form the optical waveguide section 340. In this case, etching is preferably performed using a catalyst material containing an organic compound with a polar functional group, which allows the formation of a recess having a shape nearly perpendicular to the main surface of the glass plate.

[0147] The recess structure has an opening provided in the main surface of the second glass plate and a bottom surface of the recess, where a is the minimum dimension of the opening, b is the minimum dimension of the bottom surface of the recess, and c is the depth of the recess, and angle θ expressed by the following formula (1) is referred to as the taper angle:

[0148] The taper angle θ preferably satisfies the condition 0°≦θ≦1°. By satisfying the above, an optical waveguide with uniform dimensional accuracy can be formed, and the effect of suppressing light transmission loss can be obtained in various waveguide designs formed by straight lines, arcs, etc. Furthermore, the surface roughness of the bottom and sidewalls in the recess is preferably 10 nm or less (arithmetic mean roughness Ra). By making the surface roughness 10 nm or less, transmission loss can be suppressed.

[0149] The cladding may be formed by depositing a core material in the recess, flattening the surface of the second glass plate and the surface of the core material, and then placing a material having the same refractive index as the second glass plate on top.

[0150] (Step S130) Next, the first glass substrate 210 and the second glass substrate 310 are bonded and integrated with each other to form the first optoelectronic hybrid substrate 100.

[0151] The method for bonding the first glass substrate 210 and the second glass substrate 310 is not particularly limited.

[0152] The first glass substrate 210 and the second glass substrate 310 may be bonded together by, for example, a surface activated bonding method or an atomic diffusion bonding method. Alternatively, the first glass substrate 210 and the second glass substrate 310 may be bonded together using an adhesive. Such an adhesive may be, for example, a UV-curable resin or an epoxy-based adhesive.

[0153] The thickness of the second glass substrate 310 forming the optical waveguide section 340 can be selected taking into consideration the thickness of an additional wiring layer to be formed on the first glass substrate 210. In this case, adjusting the thickness of the second glass substrate 310 depending on the presence and / or height of the additional wiring layer provides the advantage of being able to adjust the height relative to chips and other devices mounted in other locations. For example, the thickness of the additional wiring layer is 0.1 mm to 2 mm.

[0154] Through the above steps, the first optoelectronic hybrid board 100 having the above-described configuration can be manufactured.

[0155] It should be noted that the above manufacturing method is merely an example, and it will be apparent to those skilled in the art that the optoelectronic hybrid board according to an embodiment of the present invention may be manufactured by methods other than the first method.

[0156] The configuration, features, and manufacturing method of an optoelectronic hybrid board according to an embodiment of the present invention have been described above using the first optoelectronic hybrid board 100 and the second optoelectronic hybrid board 500 as examples.

[0157] However, the embodiment of the present invention is not limited to the above description. For example, various changes and modifications can be made to the configurations of the first optoelectronic hybrid board 100 and the second optoelectronic hybrid board 500.

[0158] (Aspects of the Invention) The present invention may have the following aspects.

[0159] (Aspect 1) An optoelectronic hybrid substrate comprising: a first glass substrate having a first electrical wiring section including one or more through vias in which a conductor is installed; and a second glass substrate having an optical waveguide section including a core portion, wherein the first glass substrate and the second glass substrate are bonded to each other and integrated.

[0160] (Aspect 2) The optoelectronic hybrid substrate according to aspect 1, wherein the optoelectronic hybrid substrate is configured by stacking the second glass substrate on the first glass substrate.

[0161] (Aspect 3) The optoelectronic hybrid board according to Aspect 1 or 2, wherein the first glass substrate has a first surface and a second surface facing each other, the through via extends from the first surface to the second surface, and in the first electrical wiring section, a first pattern of conductive material is disposed on the first surface and / or the second surface.

[0162] (Aspect 4) The optoelectronic hybrid board according to any one of Aspects 1 to 3, wherein the second glass substrate has a through portion, and the first electrical wiring section of the first glass substrate is arranged below the through portion in a top view of the optoelectronic hybrid board.

[0163] (Aspect 5) The optoelectronic hybrid substrate according to Aspect 4, wherein the core portion of the optical waveguide section is disposed inside the second glass substrate and extends from one end face of the second glass substrate to one side wall of the through portion.

[0164] (Aspect 6) The optoelectronic hybrid board according to aspect 4 or 5, wherein a photonic circuit (PIC) optically connected to the optical waveguide section is disposed in a part of the through portion of the second glass substrate.

[0165] (Aspect 7) The optoelectronic hybrid substrate according to any one of Aspects 1 to 6, further comprising a second pattern of a conductive material that crosses over a cross section of the core portion of the optical waveguide section in the second glass substrate.

[0166] (Aspect 8) The optoelectronic hybrid substrate of Aspect 7, wherein the first glass substrate further has a second electrical wiring section including one or more through vias having a conductor disposed therein, and the second pattern of conductive material is included in the second electrical wiring section.

[0167] (Aspect 9) The optoelectronic hybrid board according to any one of Aspects 1 to 8, wherein an electronic device is electrically connected to the first electrical wiring section of the first glass substrate.

[0168] (Aspect 10) The optoelectronic hybrid substrate according to any one of aspects 1 to 9, wherein the first glass substrate is made of a glass different from that of the second glass substrate.

[0169] (Aspect 11) The optoelectronic hybrid substrate according to any one of Aspects 1 to 9, wherein the first glass substrate is made of the same glass as the second glass substrate.

[0170] This application claims priority based on Japanese Patent Application No. 2023-147595, filed on September 12, 2023, the entire contents of which are incorporated herein by reference.

[0171] 100 First optoelectronic hybrid substrate 100-1 Modified example of first optoelectronic hybrid substrate 102 Lower surface 104 Upper surface 106 Side wall 107 Bottom surface 108 Recess 210 First glass substrate 212 First surface 214 Second surface 230 TGV 235 Conductor 240 Electrical wiring section 242 First pattern of conductive material 243 Second pattern of conductive material 310 Second glass substrate 312 Third surface 314 Fourth surface 320 Core portion 320-1 Core portion 321 Overclad portion 322 Underclad portion 333 Penetration portion 340 Optical waveguide section 340-1 Optical waveguide section 500 Second optoelectronic hybrid substrate 506 Side wall 507 Bottom surface 508 Recess 610 First glass substrate 612 First surface 614 Second surface 630 First TGV 635 First conductor 640 First electrical wiring section 642 First pattern of conductive material 643 Second pattern of conductive material 650 Second electrical wiring section 660 Second TGV 665 Second conductor 710 Second glass substrate 712 Third surface 714 Fourth surface 720 Core portion 733 Penetration portion 740 Optical waveguide section 1000 Semiconductor package 1000-1 Modified example of semiconductor package 1100 First metal redistribution layer 1102 Second metal redistribution layer 1200 First photonic circuit 1201 Second photonic circuit 1210 ASIC 1230 First passive device 1231 Second Passive Device

Claims

1. An optoelectronic hybrid board comprising: a first glass substrate having a first electrical wiring section including one or more through vias in which a conductor is installed; and a second glass substrate having an optical waveguide section including a core portion, wherein the first glass substrate and the second glass substrate are bonded to each other and integrated.

2. The optoelectronic hybrid board according to claim 1, wherein the optoelectronic hybrid board is constructed by laminating the second glass substrate on the first glass substrate.

3. The photoelectric hybrid board of claim 2, wherein the first glass substrate has a first surface and a second surface opposed to each other, the through via extends from the first surface to the second surface, and in the first electrical wiring section, a first pattern of conductive material is disposed on the first surface and / or the second surface.

4. The optoelectronic hybrid board according to claim 3, wherein the second glass substrate has a through portion, and the first electrical wiring section of the first glass substrate is disposed below the through portion when viewed from above the optoelectronic hybrid board.

5. An optoelectronic hybrid board as described in claim 4, wherein the core portion of the optical waveguide section is disposed inside the second glass substrate and extends from one end face of the second glass substrate to one side wall of the through portion.

6. The optoelectronic hybrid board according to claim 5, wherein a photonic circuit (PIC) optically connected to the optical waveguide section is disposed in a portion of the through portion of the second glass substrate.

7. The optoelectronic hybrid board according to claim 5, wherein the optoelectronic hybrid board has a second pattern of conductive material on the second surface of the first glass substrate, the second pattern intersecting the core portion of the optical waveguide section in the second glass substrate.

8. The photoelectric hybrid board of claim 7, wherein the first glass substrate further has a second electrical wiring section including one or more through vias having a conductor disposed therein, and the second pattern of conductive material is included in the second electrical wiring section.

9. The optoelectronic hybrid board according to claim 1, wherein an electronic device is electrically connected to the first electrical wiring section of the first glass substrate.

10. The optoelectronic hybrid substrate according to claim 1, wherein the first glass substrate is made of a different glass from the second glass substrate.

11. The optoelectronic hybrid substrate according to claim 1, wherein the first glass substrate is made of the same glass as the second glass substrate.

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