Semiconductor device, manufacturing method thereof and communication equipment

Abstract

The embodiment of the invention provides a semiconductor device, a manufacturing method thereof and communication equipment. The semiconductor device comprises a semiconductor substrate, an optical waveguide and a gradient refractive index lens. A plurality of refractive layers in the gradient refractive index lens are stacked in the direction perpendicular to the plane where the semiconductor substrate is located, and the refractive indexes of the multiple refractive indexes on the semiconductor substrate are gradually reduced. The first end of the gradient refractive index lens is correspondingly coupled with the optical waveguide. In the application, the second end of the gradient refractive index lens is oppositely coupled with the optical fiber, so that the light emitting spot of the semiconductor device can be matched with the optical fiber spot, the optical loss is reduced, and the coupling efficiency is improved. According to the manufacturing method provided by the invention, the gradient refractive index lens is independently manufactured and then integrated into the semiconductor device, so that the complexity of a manufacturing process of the semiconductor device can be reduced, the cost is reduced, and the mass productivity is improved. For different products, only a position for arranging the gradient refractive index lens needs to be reserved on the semiconductor substrate, so that the packaging flexibility is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a semiconductor device, a manufacturing method thereof, and a communication device. Background Art

[0002] Coupling technology between optical chips and optical fibers is currently a major development in the field of optical communications. Due to the size limitations of the waveguides in optical chips, which are designed to match the wavelengths of the communications band, the beam waist radius in edge-coupling scenarios is smaller than that of standard single-mode fibers—typically a few microns for the former and 10 microns for the latter. However, coupling technology between optical chips and optical fibers requires high coupling precision; poor precision directly reduces coupling efficiency. One of the main research areas in the industry is how to match the output beam spot of the chip waveguide with that of the single-mode fiber to achieve lower coupling losses. Summary of the Invention

[0003] The embodiments of the present application provide a semiconductor device, a manufacturing method thereof, and a communication device to solve the technical problem of improving the coupling efficiency between an optical chip waveguide and an optical fiber.

[0004] In a first aspect, an embodiment of the present application provides a semiconductor device comprising a semiconductor substrate, an optical waveguide located on one side of the semiconductor substrate, and a gradient refractive index lens; the gradient refractive index lens comprises a plurality of refractive layers, the plurality of refractive layers being stacked in a direction perpendicular to the plane of the semiconductor substrate; the refractive index of the plurality of refractive layers gradually decreases as the gradient refractive index lens moves away from the semiconductor substrate; the gradient refractive index lens comprises a first end in a first direction, the first end being coupled to the optical waveguide. The semiconductor device provided by an embodiment of the present application integrates a gradient refractive index lens, the first end of the gradient refractive index lens being coupled to the optical waveguide, and light emitted from the optical waveguide enters the gradient refractive index lens from the first end, and then, after being acted upon by the plurality of refractive layers, is emitted from the second end to form a larger mode spot. In application, coupling the second end of the gradient refractive index lens to an optical fiber can achieve matching of the light output mode spot of the semiconductor device with the mode spot of the optical fiber, thereby reducing optical loss and improving the coupling efficiency between the two.

[0005] In some embodiments, the gradient index lens has at least one irregular region on its side surface in a second direction, where the second direction intersects the first direction, and both the first and second directions are parallel to the plane of the semiconductor substrate. An irregular region is defined as a region with an uneven surface. During fabrication, the gradient index lens can be fabricated separately and then transferred to the semiconductor substrate via a pick-up process. For example, a sacrificial layer pattern is first formed on the first substrate, and then multiple functional film layers with varying refractive indices are fabricated on top of the sacrificial layer pattern. The multiple functional film layers are then etched to define a central portion, a connecting portion, and a peripheral portion according to the designed shape of the gradient index lens. After removing the sacrificial layer pattern, a hollow region is formed below the central portion and the connecting portion. The connecting portion acts as a support arm, supporting the central portion. During the pick-up process, the connecting portion is subjected to force and breaks when the central portion is picked up, forming an irregular end face, or irregular region, at the end face of the broken connecting portion. The semiconductor device provided by the embodiments of the present application allows the gradient index lens to be fabricated separately during fabrication and then integrated with the semiconductor substrate. Eliminating the need for complex coating processes on the semiconductor substrate reduces the complexity of semiconductor device manufacturing, lowering costs and increasing manufacturability. Furthermore, for different products, only a location for the gradient index lens needs to be reserved on the semiconductor substrate, increasing packaging flexibility.

[0006] In some embodiments, during the picking process, all the connecting parts are broken at the position where they are connected to the central part, which is equivalent to that the central part is basically retained in the structure of the gradient refractive index lens, the shape of the gradient refractive index lens is basically the same as the shape of the central part, and there is an irregular area in the local area of ​​the side of the gradient refractive index lens.

[0007] In some embodiments, a gradient index lens includes a main body and at least one protrusion. The main body includes a first end. The protrusion is connected to the main body and protrudes outward in a second direction. The end surface of the protrusion, facing away from the main body in the second direction, includes the irregular region. During the fabrication process, the central portion forms the main body after transfer, and the portion of the connecting portion connected to the central portion after rupture forms the protrusion. The semiconductor device provided in this embodiment allows for the gradient index lens to be fabricated separately during fabrication and then integrated with the semiconductor substrate.

[0008] In some embodiments, the thickness of the protrusion, along a direction perpendicular to the plane of the semiconductor substrate, is D1, and the thickness of the main body is D2; where D1 ≤ D2. When D1 and D2 are substantially equal, the thickness of the connecting portion (the structure used to form the protrusion after transferring the gradient index lens) is greater during semiconductor device fabrication. This provides greater support after the sacrificial layer pattern is removed, ensuring that the central portion does not collapse. A smaller protrusion thickness D1, meaning a smaller connecting portion thickness during fabrication, makes it easier to break when removing the central portion, thus reducing the difficulty of the removal process.

[0009] In some embodiments, the main body is connected to at least one protrusion on each side in the second direction. The protrusions of the gradient index lens are residual structures left after the connection portion breaks when the gradient index lens is removed from the first substrate. This embodiment ensures that during the manufacturing process, connecting portions are provided on both sides of the central portion. After the sacrificial layer pattern is removed, the connecting portions effectively support the central portion, ensuring that the central portion is suspended in the air and does not collapse.

[0010] In some other embodiments, the gradient refractive index lens further includes a substrate, which is located on a side of the plurality of refractive layers away from the semiconductor substrate.

[0011] Furthermore, the semiconductor device provided by the embodiments of the present application can be manufactured separately from the gradient index lens, which can then be integrated with the semiconductor substrate. This eliminates the need for complex coating processes on the semiconductor substrate, reducing the complexity of the semiconductor device manufacturing process, lowering costs, and increasing manufacturability. Furthermore, for different products, only a location for the gradient index lens needs to be reserved on the semiconductor substrate, increasing packaging flexibility.

[0012] In some embodiments, the semiconductor device includes a support surface, and the gradient index lens is located on a side of the support surface away from the semiconductor substrate. The gradient index lens is bonded to the support surface via an adhesive layer, or the gradient index lens is secured to the support surface via laser welding. In some embodiments, the gradient index lens is bonded to the support surface via van der Waals forces.

[0013] In some embodiments, the semiconductor device comprises a first groove; the first groove extends through a portion of the semiconductor device's film layer in a direction perpendicular to the plane of the semiconductor substrate; at least a portion of the gradient index lens is located within the first groove; the first groove includes a first sidewall, the first sidewall exposing an end face of the optical waveguide, the end face exposed by the first sidewall being the first end face; within the first groove, the first end faces the first end face. When manufacturing the semiconductor device provided in this embodiment, the first groove must first be formed on the semiconductor substrate, and then the gradient index lens integration process must be performed.

[0014] In some embodiments, the bottom surface of the gradient index lens near the semiconductor substrate is a first bottom surface, and the end of the first end surface near the semiconductor substrate is a first bottom end, with the first bottom surface and the first bottom end aligned. This arrangement allows light emitted from the light waveguide to smoothly enter the lowest refractive layer of the gradient index lens, thereby achieving high coupling efficiency between the two.

[0015] In some embodiments, the semiconductor device includes a cover layer located on a side of the optical waveguide remote from the semiconductor substrate, and a gradient index lens located on a side of the cover layer remote from the optical waveguide. A first end of the gradient index lens partially overlaps the optical waveguide in a direction perpendicular to the semiconductor substrate. During fabrication of the semiconductor device provided by this embodiment, a separately fabricated gradient index lens can be transferred onto the cover layer and bonded to the cover layer, resulting in evanescent wave coupling between the gradient index lens and the optical waveguide.

[0016] In some embodiments, the cover layer includes a second groove; the depth of the second groove, along a direction perpendicular to the plane of the semiconductor substrate, is less than the thickness of the cover layer; and at least a portion of the gradient index lens is located within the second groove. If the cover layer is relatively thick, the second groove can be first formed in the cover layer, and then the gradient index lens can be transferred into the second groove to couple with the optical waveguide, thereby ensuring evanescent wave coupling efficiency.

[0017] In some embodiments, the material of the plurality of refractive layers includes silicon oxynitride.

[0018] In a second aspect, based on the same inventive concept, an embodiment of the present application further provides a method for manufacturing a semiconductor device, the method comprising:

[0019] providing a semiconductor substrate, wherein an optical waveguide is formed on one side of the semiconductor substrate;

[0020] The gradient refractive index lens is transferred to one side of the semiconductor substrate. The gradient refractive index lens includes a first end in a first direction, and the first end is set to be coupled with the optical waveguide. The gradient refractive index lens includes multiple refractive layers, and the multiple refractive layers are stacked in a direction perpendicular to the plane where the semiconductor substrate is located.

[0021] Using the manufacturing method provided in the embodiments of this application, a gradient-index lens is fabricated separately and then integrated with a semiconductor substrate. This eliminates the need for complex coating processes on the semiconductor substrate, reducing the complexity of semiconductor device manufacturing, lowering costs, and increasing manufacturability. Furthermore, for different products, only a location for the gradient-index lens needs to be reserved on the semiconductor substrate, increasing packaging flexibility.

[0022] In some embodiments, before transferring the gradient refractive index lens to one side of the semiconductor substrate, the manufacturing method further includes manufacturing the gradient refractive index lens; wherein the manufacturing method includes:

[0023] forming a sacrificial layer pattern on the first substrate;

[0024] Forming a plurality of functional film layers with gradually changing refractive indices on a side of the sacrificial layer pattern away from the first substrate;

[0025] Performing patterning on the plurality of functional film layers to form a first pattern, the first pattern including a peripheral portion, a central portion, and a connecting portion, wherein the peripheral portion surrounds the sacrificial layer pattern, the central portion and the connecting portion are located above the sacrificial layer pattern, and the connecting portion connects the central portion and the peripheral portion;

[0026] The sacrificial layer pattern is removed so that the central portion and the connecting portion are suspended;

[0027] Picking up the central portion from the first substrate to obtain a gradient refractive index lens, wherein the connecting portion is broken to form an irregular cross-section when picking up the central portion, and the plurality of functional film layers form a plurality of refractive layers of the gradient refractive index lens;

[0028] The gradient refractive index lens is transferred to one side of the semiconductor substrate, comprising: the gradient refractive index lens has at least one irregular area on a side surface in a second direction, the irregular end surface is the irregular area, the second direction intersects the first direction, and the first direction and the second direction are both parallel to the plane where the semiconductor substrate is located.

[0029] In other embodiments, a gradient refractive index lens is obtained by picking up a central portion from a first substrate, comprising: connecting a broken connecting portion to the central portion to form a gradient refractive index lens, wherein the central portion is a main body of the gradient refractive index lens, and the broken connecting portion is a convex portion of the gradient refractive index lens;

[0030] The gradient refractive index lens is transferred to one side of the semiconductor substrate, comprising: a main body of the gradient refractive index lens including a first end, and a protrusion connected to the main body and protruding outward along a second direction;

[0031] The gradient refractive index lens has at least one irregular area on the side surface in the second direction, including: an end surface of the protrusion away from the main body along the second direction includes the irregular area.

[0032] In some embodiments, before transferring the gradient refractive index lens to one side of the semiconductor substrate, the manufacturing method further includes: manufacturing the gradient refractive index lens; wherein the manufacturing method includes:

[0033] forming a plurality of functional film layers on the second substrate;

[0034] Cutting the second substrate and the plurality of functional film layers to form a gradient refractive index lens, wherein the plurality of functional film layers form a plurality of refractive layers, and the second substrate forms a substrate;

[0035] Transferring the gradient refractive index lens to one side of a semiconductor substrate includes: transferring the gradient refractive index lens onto the semiconductor substrate using a flip-chip process, wherein the substrate is located on a side of the plurality of refractive layers away from the semiconductor substrate; the gradient refractive index lens includes a first end in a first direction, and the first end is configured to be coupled to the optical waveguide.

[0036] In some embodiments, before the process of transferring the gradient refractive index lens onto the semiconductor substrate, the manufacturing method further includes: forming a first groove penetrating a portion of the film layer on the semiconductor substrate; the first groove includes a first sidewall, the first sidewall exposes an end face of the optical waveguide, and the end face exposed by the first sidewall is the first end face; transferring the gradient refractive index lens onto the semiconductor substrate includes: placing at least a portion of the gradient refractive index lens in the first groove, and making the first end opposite to the first end face.

[0037] In some embodiments, the semiconductor device includes a covering layer, which is located on a side of the optical waveguide away from the semiconductor substrate; transferring the gradient refractive index lens onto the semiconductor substrate includes: placing the gradient refractive index lens on a side of the covering layer away from the optical waveguide; and the first end partially overlaps with the optical waveguide along a direction perpendicular to the plane of the semiconductor substrate.

[0038] On the third aspect, based on the same inventive concept, an embodiment of the present application also provides a communication device, including the semiconductor device provided by any embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of a semiconductor device provided in an embodiment of the present application;

[0040] Figure 2A Schematic diagram of the gradient refractive index lens to expand the optical waveguide mode spot;

[0041] Figure 2B Schematic diagram of coupling between semiconductor device and optical fiber;

[0042] Figure 3 A schematic diagram of another semiconductor device provided in an embodiment of the present application;

[0043] Figure 4 for Figure 3 A schematic cross-sectional view at the midline AA′;

[0044] Figure 5 A flow chart of a method for manufacturing a semiconductor device provided in an embodiment of the present application;

[0045] Figure 6 is a top view after step S101;

[0046] Figure 7 is a schematic diagram of the first graphic after step S103 in another manufacturing method;

[0047] Figure 8 A schematic cross-sectional view of the position of the tangent line BB′ in the top view of step S103;

[0048] Figure 9 A schematic cross-sectional view of the position of the tangent line CC′ in the top view of step S103;

[0049] Figure 10 A schematic cross-sectional view at the position of the tangent line DD′ in the top view of step S104;

[0050] Figure 11 A schematic cross-sectional view of the position of the tangent line EE′ in the top view of step S104;

[0051] Figure 12 A schematic diagram of a gradient refractive index lens obtained by the manufacturing method provided in an embodiment of the present application;

[0052] Figure 13 for Figure 3 A schematic cross-sectional view at the mid-tangent line FF′;

[0053] Figure 14 for Figure 3 Another cross-sectional view at the mid-tangent line FF′;

[0054] Figure 15 A schematic diagram of another semiconductor device provided by an embodiment of the present invention;

[0055] Figure 16 A flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application;

[0056] Figure 17 A schematic diagram of another semiconductor device provided in an embodiment of the present application;

[0057] Figure 18 A flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application;

[0058] Figure 19 A schematic diagram of another semiconductor device provided in an embodiment of the present application;

[0059] Figure 20 A flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application;

[0060] Figure 21 A schematic diagram of another semiconductor device provided in an embodiment of the present application;

[0061] Figure 22 A schematic diagram of another semiconductor device provided in an embodiment of the present application;

[0062] Figure 23 A simulation test diagram of a semiconductor device provided in an embodiment of the present application;

[0063] Figure 24 A top view of another semiconductor device provided in an embodiment of the present application;

[0064] Figure 25 A top view of another semiconductor device provided in an embodiment of the present application;

[0065] Figure 26 A top view of another semiconductor device provided in an embodiment of the present application;

[0066] Figure 27 A schematic diagram of an application of a semiconductor device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] The present invention provides a semiconductor device with a gradient-index lens disposed thereon. By coupling the gradient-index lens with an optical waveguide, the small mode spot of the optical waveguide can be enlarged to match the mode spot of an optical fiber. This semiconductor device can be used in scenarios where optical chips (such as silicon photonic chips) are coupled to optical fibers, such as access networks, transport networks, data centers, and routers that require optical modules.

[0068] Figure 1 A schematic diagram of a semiconductor device provided in an embodiment of the present application is provided. Figure 2A Schematic diagram of the principle of expanding the optical waveguide mode spot using a gradient refractive index lens. Figure 2B This is a schematic diagram of coupling between semiconductor devices and optical fibers. Figure 1 As shown, the semiconductor device 00 includes a substrate 03, and an optical waveguide 01 and a gradient refractive index lens 02 located on one side of the substrate 03. The manufacturing method of this structure is to form multiple layers of material layers 021 with gradient refractive index through multiple coating and etching processes during micro-nano processing. The multiple layers of material layers 021 form the gradient refractive index lens 02. The refractive index of the multiple layers of material layers 021 decreases layer by layer from bottom to top, and the bottom layer of material layer 021 is connected to the optical waveguide 01 in the semiconductor device 00. Figure 2A As shown, the arrows indicate the direction of light transmission. The gradient refractive index of the multi-layer material layer 021 in the gradient refractive index lens 02 can gradually pull the light at the bottom to the upper layer, and can expand the light mode spot on the side of the gradient refractive index lens 02. Figure 2BAs shown, the side surface of the gradient index lens 02 in the semiconductor device 00 corresponds to the optical fiber 04. Taking optical fiber 04 as a single-mode fiber, for example, its beam waist radius is approximately 10 μm, and the size of the optical fiber's mode spot is related to its beam waist radius. In practice, the size of the gradient index lens 02 can be designed based on the optical fiber's design requirements and the mode spot size of optical fiber 04. The side surface of the gradient index lens 02 serves as a coupling surface facing the optical fiber, so that the mode spot enlarged by the gradient index lens 02 is similar in size to the mode spot of optical fiber 04. This allows the light output mode spot of the semiconductor device 00 to match the mode spot of the optical fiber 04, reducing optical loss and improving the coupling efficiency between the two.

[0069] Figure 1 The semiconductor device 00 provided in the embodiment directly manufactures the gradient refractive index lens 02 on the substrate 03. This requires multiple coatings, exposures, and etchings with different refractive indices on the optical waveguide 01 after the optical waveguide 01 is manufactured. This process is complex and has low process stability. Taking the semiconductor device 00 as a silicon-based chip as an example, the same gradient refractive index lens manufacturing process needs to be performed on each batch of wafers, which is inflexible, affects the yield rate, and thus affects mass production. Based on this, the embodiment of the present application also provides a method for manufacturing a semiconductor device that can be used to manufacture the semiconductor device provided in the embodiment of the present application. The manufacturing method includes:

[0070] Step S001: providing a semiconductor substrate, wherein an optical waveguide is formed on one side of the semiconductor substrate.

[0071] Step S002: transferring a gradient refractive index lens to one side of a semiconductor substrate, wherein the gradient refractive index lens includes a first end in a first direction, and the first end is configured to be coupled to the optical waveguide; the gradient refractive index lens includes a plurality of refractive layers, and the plurality of refractive layers are stacked in a direction perpendicular to the plane of the semiconductor substrate.

[0072] In the embodiments of the present application, a gradient-index lens is fabricated separately during manufacturing. The gradient-index lens is then transferred to a semiconductor substrate using a transfer or flip-chip process to couple with the corresponding optical waveguide, resulting in a device capable of low-loss optical coupling with an optical fiber. This eliminates the need for complex processing on the semiconductor substrate, reducing process complexity, lowering costs, and increasing manufacturability. For different products, only a location for the gradient-index lens needs to be reserved on the semiconductor substrate, increasing packaging flexibility.

[0073] Figure 3 A schematic diagram of another semiconductor device provided in an embodiment of the present application is shown. Figure 4 for Figure 3 A schematic cross-sectional view at the midline AA′. Figure 3 A top view of a semiconductor device. Figure 3and Figure 4 Let's see Figure 3 As shown, the semiconductor device includes a semiconductor substrate 10, and an optical waveguide 20 and a gradient refractive index lens 30 located on one side of the semiconductor substrate 10. In one embodiment, the semiconductor substrate 10 is a silicon-based chip. The semiconductor substrate 10 includes active devices and / or passive devices. The semiconductor substrate 10 can be used as a driver integrated circuit, a transimpedance amplifier, a semiconductor laser, an optical multiplexer / demultiplexer, etc., and can also integrate other logic components, memory, or integrated passive components thereon. It can also integrate a processing chip, a central processing unit chip, an imaging chip, an audio chip, or a data chip, etc.

[0074] The gradient refractive index lens 30 includes a plurality of refractive layers 301, which are stacked in a direction perpendicular to the plane of the semiconductor substrate 10. The refractive index of the plurality of refractive layers 301 gradually decreases on the side of the semiconductor substrate 10 where the gradient refractive index lens is located, in a direction perpendicular to the plane of the semiconductor substrate 10 and away from the semiconductor substrate 10. Figure 4 The number of refractive layers 301 is for illustration only. The gradient index lens 30 includes a main body 31 and at least one protruding portion 32. The main body 31 includes a first end 30-1 and a second end 30-2 in a first direction a. The first end 30-1 is coupled to the optical waveguide 20. The protruding portion 32 is connected to the main body 31 and protrudes outward along a second direction b. The second direction b intersects the first direction a, and both the first direction a and the second direction b are parallel to the plane of the semiconductor substrate 10. Typically, the second direction b and the first direction a are perpendicular to each other. Figure 3 The positions and numbers of the protrusions 32 are only schematic representations and are not intended to limit the present application. In addition, the end face of the protrusion 32 away from the main body 31 along the second direction b is an irregular end face, which will be illustrated in the following related drawings. Figure 4 The figure shows a cover layer 40 disposed on the side of the optical waveguide 20 away from the semiconductor substrate 10. Optionally, the cover layer 40 is made of silicon dioxide. The cover layer 40 is disposed on the optical waveguide 20 to ensure good transmission of light energy within the waveguide and to protect the optical waveguide 20 and maintain the stability of the waveguide structure.

[0075] The semiconductor device provided in the embodiments of the present application integrates a gradient refractive index lens 30. The first end 30-1 of the gradient refractive index lens 30 is coupled to the optical waveguide 20. Light emitted from the optical waveguide 20 enters the gradient refractive index lens 30 through the first end 30-1, then exits at the second end 30-2 after being acted upon by multiple refractive layers 301, forming a larger optical pattern. In applications, the second end 30-2 of the gradient refractive index lens 02 is coupled to an optical fiber, thereby matching the optical pattern of the semiconductor device with the optical fiber, reducing optical loss and improving coupling efficiency between the two. Furthermore, during fabrication, the semiconductor device provided in the embodiments of the present application can be fabricated separately from the gradient refractive index lens 30, and then integrated with the semiconductor substrate 10. This eliminates the need for complex coating processes on the semiconductor substrate 10, reducing the complexity of the semiconductor device manufacturing process, lowering costs, and increasing manufacturability. Furthermore, for different products, only a location for the gradient refractive index lens 30 needs to be reserved on the semiconductor substrate 10, increasing packaging flexibility.

[0076] The present application also provides a method for manufacturing a semiconductor device. First, a gradient refractive index lens 30 is manufactured separately. Then, the gradient refractive index lens 30 is transferred onto the semiconductor substrate 10 by a transfer process such as a transfer printing process, so that the gradient refractive index lens 30 and the optical waveguide 20 are located on the same side of the semiconductor substrate 10. The manufacturing method provided by the present application can be used to manufacture a semiconductor device. Figure 3 The semiconductor device provided by the embodiment. Figure 5 A flow chart of a method for manufacturing a semiconductor device provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, the manufacturing method at least includes steps S101 to S106.

[0077] Step S101: forming a sacrificial layer pattern 020 on a first substrate 010; wherein, a whole sacrificial layer can be formed first, and then a patterning process is used to form the desired sacrificial layer pattern 020. The material of the first substrate 010 is not limited, and the first substrate 010 can be a glass substrate or a silicon substrate. Figure 5 Only one sacrificial layer pattern 020 on the first substrate 010 is shown schematically. Figure 6 is a top view after step S101. Figure 6 As shown, multiple sacrificial layer patterns 020 are simultaneously formed on a first substrate 010, so that multiple gradient refractive index lenses 30 can be simultaneously manufactured on a single first substrate 010. In some embodiments, the first substrate 010 is a silicon substrate, and a silicon oxide layer can be first formed on the silicon substrate, and then the sacrificial layer pattern 020 can be formed on the silicon oxide layer. In other embodiments, the sacrificial layer pattern 020 can also be directly formed on the silicon substrate.

[0078] Step S102: Multiple functional film layers 0301 with gradually varying refractive indices are formed on the side of the sacrificial layer pattern 020 away from the first substrate 010. The refractive indices of the multiple functional film layers 0301 gradually decrease as they move away from the first substrate 010. In one embodiment, the material of the functional film layers 0301 includes silicon oxynitride. The refractive index of the functional film layers 0301 is controlled by controlling the nitrogen content during fabrication.

[0079] Step S103: The plurality of functional film layers 0301 are patterned to form a first pattern 030. The first pattern 030 includes a peripheral portion 001, a central portion 002, and a connecting portion 003. The peripheral portion 001 surrounds the sacrificial layer pattern 020. The central portion 002 and the connecting portion 003 are located above the sacrificial layer pattern 020. The connecting portion 003 is connected between the central portion 002 and the peripheral portion 001. The first pattern 030 also includes a hollow area ( Figure 5 The hollow area separates the central portion 002 from the peripheral portion 001 , and the hollow area exposes the sacrificial layer pattern 020 . Figure 5 The shape of the central portion 002 is only schematically shown. In practice, the shape of the central portion 002 can be manufactured according to the desired shape of the gradient refractive index lens 30. Figure 5 The shape and position of the middle connection portion 003 are schematically shown. The connection portion 003 is provided to support the central portion 002 in a suspended state after the sacrificial layer pattern 020 is removed, facilitating subsequent transfer of the central portion 002. The number and position of the connection portions 003 can be designed based on the shape of the central portion 002. Figure 7 This is a schematic diagram of the first graphic after step S103 in another production method, using Figure 7 The shape of the gradient refractive index lens 30 finally obtained by the first pattern 030 provided in the embodiment can be the same as Figure 3 The shapes of the gradient index lenses 30 in the embodiments are substantially the same.

[0080] Figure 5 FIG shows a top view after step S103. Figure 8 This is a cross-sectional diagram at the position of the tangent line BB′ in the top view of step S103. Figure 9 FIG. 1 is a cross-sectional view of the position of the tangent line CC′ in the top view of step S103. Figure 8 It can be seen that the peripheral portion 001 is spaced apart from the central portion 002, and the hollow area 004 exposes the sacrificial layer pattern 020. Figure 9 It can be seen that the connecting portion 003 connects the peripheral portion 001 and the central portion 002 .

[0081] Step S104: removing the sacrificial layer pattern 020, so that the central portion 002 and the connecting portion 003 are suspended. Figure 5FIG. 1 shows a top view after step S104 . After the sacrificial layer pattern 020 is removed, the first pattern 030 including the hollow area exposes the first substrate 010 . Figure 10 A cross-sectional view at the position of the tangent line DD′ in the top view of step S104 is shown. Figure 11 is a cross-sectional view at the position of the tangent line EE′ in the top view of step S104, Figure 10 and Figure 11 It can be seen that after removing the sacrificial layer pattern 020, the central portion 002 and the connecting portion 003 are suspended in the air. The connecting portion 003 is equivalent to a support arm, which is used to support the central portion 002 to ensure that it does not fall.

[0082] Step S105 : using a transfer jig 005 to pick up the central portion 002 from the first substrate 010 to obtain a gradient refractive index lens 30 , wherein the connecting portion 003 is broken when picking up the central portion 002 so that the central portion 002 is separated from the first substrate 010 . Figure 5 The broken connecting portion 003 shown in the figure is connected to the central portion 002 to form the gradient index lens 30. The multiple functional film layers 0301 form the multiple refractive layers of the gradient index lens 30. The broken connecting portion 003 forms an irregular cross-section, which ultimately remains on the gradient index lens 30 to form an irregular area on its side. The irregular area can also be understood as a flat surface, that is, formed by the random fracture of the connecting portion 003.

[0083] When the material of the multiple functional film layers 0301 includes silicon oxynitride, the material of the multiple refractive layers also includes silicon oxynitride. Furthermore, the transfer jig 005 can be a stamp made of a polymer material such as polydimethylsiloxane (PDMS), and a transfer process is used to remove the center portion 002 from the first substrate 010.

[0084] The gradient refractive index lens 30 can be manufactured through steps S101 to S105 . Figure 12 Schematic diagram of a gradient refractive index lens obtained by the manufacturing method provided in the embodiment of the present application. Figure 12 As shown, the gradient index lens 30 includes a main body 31 and a protruding portion 32. The central portion 002 is the main body 31 of the gradient index lens 30, and the broken connecting portion 003 is the protruding portion 32 of the gradient index lens 30. The main body 31 includes a first end 30-1 and a second end 30-2 in a first direction a. The protruding portion 32 is connected to the main body 31 and protrudes outward along a second direction b, which intersects the first direction a.

[0085] Step S106: Transfer the gradient index lens 30 onto the semiconductor substrate 10, and arrange the first end 30-1 of the main body 31 to be coupled to the optical waveguide 20. Optionally, the gradient index lens 30 is fixed to one side of the semiconductor substrate 10 by bonding, for example, the gradient index lens 30 is bonded to a supporting surface on the semiconductor substrate 10 by van der Waals forces.

[0086] An embodiment of the present application provides a method for fabricating a semiconductor device. First, a sacrificial layer pattern 020 is formed on a first substrate 010. Multiple functional film layers 0301 with gradually varying refractive indices are then formed on the sacrificial layer pattern 020. The multiple functional film layers 0301 are then etched to form a first pattern 030 according to the desired shape of a gradient refractive index lens 30. After removing the sacrificial layer pattern 020, the center portion 002 and the connecting portion 003 in the first pattern 030 are left suspended. A transfer process is used to remove the center portion 002 from the first substrate 010. If the connecting portion 003 breaks during the transfer process, the broken connecting portion 003 is transferred together with the center portion 002. The broken connecting portion 003 and the center portion 002 constitute the gradient refractive index lens 30. After the gradient refractive index lens 30 is fabricated separately, it is then transferred onto the semiconductor substrate 10 and coupled to the optical waveguide 20 to obtain the semiconductor device. This application allows for the simultaneous fabrication of multiple gradient-index lenses 30 on the first substrate 010, eliminating the need for complex coating processes on the semiconductor substrate 10. This reduces the complexity of semiconductor device manufacturing, lowers costs, and increases manufacturability. Furthermore, for different products, only a location for the gradient-index lenses 30 needs to be reserved on the semiconductor substrate 10, increasing packaging flexibility.

[0087] In some embodiments, Figure 13 for Figure 3 A cross-sectional diagram at the midline FF'. Figure 13 As shown, the end surface of the protrusion 32 away from the main body 31 along the second direction b includes an irregular area, or in other words, the end surface of the protrusion 32 away from the main body 31 along the second direction b is an irregular end surface. Figure 13 The irregular end surface of the protrusion 32 is a cross section formed when the connecting portion 003 is broken and separated from the peripheral portion 001 in step S105. Figure 13 The schematic cross-sectional view is only for simplification and does not illustrate the multiple refractive layers in the gradient refractive index lens 30. Figure 14 、 Figure 15 The refractive layer is not shown either, and other similar figures can be used as a reference for understanding.

[0088] Figure 5In the embodiment, step S105 illustrates the situation where the broken connecting portion 003 remains on the gradient index lens 30 to form a protrusion 32. In other embodiments, according to the process settings, when the center portion 002 is picked up from the first substrate 010 using the transfer jig 005 in step S105, the connecting portion 003 is broken at the connection portion with the center portion 002. In this case, the resulting gradient index lens 30 does not have a protrusion structure, and only retains the irregular section formed when the connecting portion 003 is broken. That is, the gradient index lens has an irregular area on the side surface in the second direction. Figure 7 For example, there are four connecting parts 003 connected to the central part 002. When picking up the central part 002, it is possible that all four connecting parts 003 are broken at the positions where they are connected to the central part 002. Then the shape of the gradient refractive index lens 30 obtained by the final transfer is basically the same as the shape of the central part 002. Since the breaking positions of the connecting parts 003 are random during the process, Figure 7 The gradient index lens 30 finally obtained in the embodiment may still have 1, 2, 3 or 4 protrusions.

[0089] like Figure 13 As shown, along a direction e perpendicular to the plane of the semiconductor substrate 10, the thickness of the protrusion 32 is D1, and the thickness of the main body 31 is D2; D1 and D2 are substantially equal. Therefore, during semiconductor device fabrication, the first pattern 030 obtained by the patterning process in step S103 has substantially equal thicknesses between the connecting portion 003 and the central portion 002. This thicker connecting portion 003 provides a stronger support after the sacrificial layer pattern 020 is removed, ensuring that the central portion 002 does not collapse.

[0090] In some embodiments, the height of the gradient index lens 30 is in the range of 5 to 15 μm. Figure 13 The thickness D1 of the protrusion 32 shown is in the range of 5 to 15 μm.

[0091] In another embodiment, Figure 14 for Figure 3 Another cross-sectional diagram at the mid-tangent line FF′. Figure 14As shown, the thickness D1 of the protrusion 32 is less than the thickness D2 of the main body 31. In this embodiment, the thickness D1 of the protrusion 32 is relatively small, that is, the thickness of the connection portion 003 in the manufacturing process is relatively small. In step S103, a half-grayscale mask process can be used to etch the first pattern 030, so that the thickness of the connection portion 003 is smaller than the thickness of the central portion 002; or a two-step etching process can be used to obtain the first pattern 030, so that the thickness of the connection portion 003 is smaller than the thickness of the central portion 002. While ensuring that the connection portion 003 can support the central portion 002 after removing the sacrificial layer pattern 020, the thickness of the connection portion 003 is relatively small. Therefore, the connection portion 003 is more likely to break when picking up the central portion 002, which can reduce the difficulty of the picking process in step S105.

[0092] In some embodiments, as Figure 3 As shown, the main body 31 is connected to at least one protrusion 32 on both sides in the second direction b. Figure 5 The manufacturing method provided in the embodiment is used to manufacture a semiconductor device. It can be seen that the protrusion 32 of the gradient refractive index lens 30 is the residual structure after the connection portion 003 is broken when the gradient refractive index lens 30 is picked up on the first substrate 010. In the manufacturing process, the connection portion 003 is connected between the central portion 002 and the peripheral portion 001. The connection portions 003 are respectively provided on both sides of the central portion 002 to ensure effective support for the central portion 002 after the sacrificial layer pattern is removed, ensuring that the central portion 002 is suspended and does not collapse. When the gradient refractive index lens 30 is picked up in step S105, the break position of each connection portion 003 is random, for example Figure 5 In the embodiment, three connecting portions 003 are respectively provided on both sides of the central portion 002 , and the gradient refractive index lens 30 obtained after step S105 includes at most six protruding portions 32 .

[0093] An embodiment of the present invention also provides another semiconductor device, Figure 15 A schematic diagram of another semiconductor device provided by an embodiment of the present invention, such as Figure 15 As shown, the gradient index lens 30 further includes a substrate 302, which is located on a side of the multiple refractive layers 301 away from the semiconductor substrate 10. The refractive index of the multiple refractive layers 301 gradually decreases on the side of the semiconductor substrate where the gradient index lens is located, in a direction perpendicular to the plane of the semiconductor substrate 10 and away from the semiconductor substrate 10. The gradient index lens 30 includes a first end 30-1 and a second end 30-2 in a first direction a. The first end 30-1 is coupled to the optical waveguide 20. Figure 15The figure shows that a cover layer 40 is also provided on the side of the optical waveguide 20 facing away from the semiconductor substrate 10. The first end 30-1 of the gradient index lens 30 is coupled to the optical waveguide 20. Light emitted from the optical waveguide 20 enters the gradient index lens 30 through the first end 30-1, then passes through multiple refractive layers 301 and exits at the second end 30-2, forming a larger optical beam pattern. In applications, the second end 30-2 of the gradient index lens 02 is coupled to an optical fiber, thereby matching the optical beam pattern of the semiconductor device with the optical fiber beam pattern, reducing optical loss and improving coupling efficiency between the two. Furthermore, the semiconductor device provided by this embodiment can first be fabricated separately from the gradient index lens 30, and then flip-chip transferred to the semiconductor substrate 10. This eliminates the need for complex coating processes on the semiconductor substrate 10, reducing the complexity of the semiconductor device manufacturing process, lowering costs, and increasing mass production. Furthermore, for different products, only a location for the gradient index lens 30 needs to be reserved on the semiconductor substrate 10, increasing packaging flexibility.

[0094] The embodiment of the present application does not limit the material of the substrate 302 , and the substrate 302 may be a glass substrate or a silicon-based substrate.

[0095] The present application also provides a method for manufacturing a semiconductor device, which can be used to manufacture Figure 15 The semiconductor device provided by the embodiment.

[0096] Figure 16 This is a flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application. Figure 16 As shown, the production method includes:

[0097] Step S201 : forming a plurality of functional film layers 0301 on a second substrate 040 ; wherein, the refractive index of the plurality of functional film layers 0301 gradually increases in a direction away from the second substrate 040 .

[0098] Step S202: The second substrate 040 and the plurality of functional film layers 0301 are cut to form a gradient index lens 30. The plurality of functional film layers 0301 form the plurality of refractive layers 301, and the second substrate 040 forms the substrate 302. In this step, the gradient index lens 30 is diced according to the desired size to obtain the desired gradient index lens 30.

[0099] Step S203: The gradient refractive index lens 30 is transferred onto the semiconductor substrate 10 using a flip-chip process, wherein the substrate 302 is located on a side of the multiple refractive layers 301 away from the semiconductor substrate 10; the gradient refractive index lens 30 includes a first end 30-1 and a second end 30-2 in the first direction a, and the first end 30-1 of the gradient refractive index lens 30 is configured to be coupled to the optical waveguide 20.

[0100] A flip-chip process is used to transfer the separately fabricated gradient index lens 30 onto the semiconductor substrate 10, completing the integration of the gradient index lens 30 into the semiconductor device. This eliminates the need for complex coating processes on the semiconductor substrate 10, reducing the complexity of semiconductor device manufacturing, lowering costs, and increasing manufacturability. Furthermore, for different products, only a location for the gradient index lens 30 needs to be reserved on the semiconductor substrate 10, increasing packaging flexibility.

[0101] In some embodiments, before step S203 , a thinning process may be added to reduce the thickness of the substrate 302 of the gradient refractive index lens 30 .

[0102] In addition, in step S203, the gradient refractive index lens 30 is transferred onto the semiconductor substrate 10. The gradient refractive index lens 30 can be bonded to the supporting surface on the semiconductor substrate 10 through van der Waals forces, or the gradient refractive index lens 30 can be bonded and fixed to the supporting surface through a dispensing process, or the gradient refractive index lens 30 can be fixed on the supporting surface by laser welding. Figure 17 Another semiconductor device schematic diagram provided in an embodiment of the present application is as follows: Figure 17 As shown, the semiconductor device includes a carrier surface ( Figure 17 The gradient index lens 30 is located on the side of the support surface away from the semiconductor substrate 10; the support surface is the base surface of the semiconductor substrate 10 that supports the gradient index lens 30. The gradient index lens 30 and the support surface are bonded by an adhesive layer 60.

[0103] In some embodiments, the semiconductor device has a first groove, and at least a portion of the gradient index lens 30 is located in the first groove 51. Figure 4 As shown, the semiconductor device has a first groove 51; along a direction perpendicular to the plane of the semiconductor substrate 10, the first groove 51 penetrates part of the film layer of the semiconductor device; at least part of the gradient refractive index lens 30 is located in the first groove 51. The first groove 51 includes a first sidewall ( Figure 4 (not shown), the first sidewall exposes one end face of the optical waveguide 20, which is the first end face 20-1. Within the first groove 51, the first end 30-1 is opposite the first end face 20-1. When manufacturing the semiconductor device provided in this embodiment, the first groove 51 must first be formed on the semiconductor substrate 10, and then the gradient index lens 30 is integrated.

[0104] like Figure 4As shown, the bottom surface of the gradient refractive index lens 30 close to the semiconductor substrate 10 is the first bottom surface 30-3, and the end of the first end surface 20-1 close to the semiconductor substrate 10 is the first bottom end ( Figure 4 This arrangement allows light emitted from the optical waveguide 20 to smoothly enter the lowest refractive layer of the gradient index lens 30, thereby achieving a higher coupling efficiency between the two.

[0105] like Figure 4 As shown, a refractive layer 301 of the gradient index lens 30 that is closest to the semiconductor substrate 10 is connected to the optical waveguide 20. This arrangement can ensure the optical coupling efficiency between the gradient index lens 30 and the optical waveguide 20.

[0106] The present invention also provides another method for manufacturing a semiconductor device. Figure 18 A flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application is shown in FIG. Figure 18 As shown, the production method includes:

[0107] Step S1061: A first groove 51 is formed on the semiconductor substrate 10 by an etching process. The first groove 51 penetrates a portion of the film layer on the semiconductor substrate 10. The first groove 51 includes a first sidewall 511. The first sidewall 511 exposes an end face of the optical waveguide 20. The end face exposed by the first sidewall 511 is the first end face 20-1. Figure 18 Taking the case where the cover layer 40 is provided on the side of the optical waveguide 20 away from the semiconductor substrate 10 as an example, in step S1061 , at least the cover layer 40 is etched to obtain the first groove 51 .

[0108] Step S1062 : placing at least a portion of the gradient index lens 30 in the first groove 51 , and making the first end 30 - 1 of the gradient index lens 30 face the first end surface 20 - 1 .

[0109] use Figure 18 The manufacturing method provided in the embodiment can produce Figure 4 In the semiconductor device provided in the embodiment, during fabrication, a portion of the film layer on the semiconductor substrate 10 is etched to form a first groove 51, such that a sidewall of the first groove 51 exposes an end portion of the optical waveguide 20. A separately fabricated gradient refractive index lens 30 is then placed within the first groove 51, such that the first end 30-1 of the gradient refractive index lens 30 is opposite to the first end face 20-1. This achieves the integration of the gradient refractive index lens 30 into the semiconductor device.

[0110] In addition, if Figure 15The gradient refractive index lens 30 is transferred by the flip chip process, and at least part of the gradient refractive index lens 30 is located in the first groove 51. When manufacturing the semiconductor device, before step S203, the first groove 51 is first made on the semiconductor substrate 10, and then step S203 is performed to obtain Figure 15 The semiconductor device shown.

[0111] In other embodiments, Figure 19 Another semiconductor device schematic diagram provided in an embodiment of the present application is as follows: Figure 19 As shown, the semiconductor device includes a cover layer 40, which is located on the side of the optical waveguide 20 away from the semiconductor substrate 10. The gradient index lens 30 is located on the side of the cover layer 40 away from the optical waveguide 20. In a direction e perpendicular to the semiconductor substrate 10, the first end 30-1 of the gradient index lens 30 partially overlaps the optical waveguide 20. During fabrication of the semiconductor device provided in this embodiment, the separately fabricated gradient index lens 30 can be transferred onto the cover layer 40 and bonded to the cover layer 40, so that the gradient index lens 30 and the optical waveguide 20 are coupled via evanescent wave coupling.

[0112] In some embodiments, as Figure 19 As shown, the length of the portion where the gradient index lens 30 overlaps the optical waveguide 20 is L, and L≤500 μm. This arrangement can ensure the efficiency of the evanescent wave coupling between the gradient index lens 30 and the optical waveguide 20.

[0113] The present application also provides another method for manufacturing a semiconductor device, which can be used to manufacture Figure 19 The semiconductor device shown. Figure 20 A flow chart of another method for manufacturing a semiconductor device provided in an embodiment of the present application, such as Figure 20 As shown, the production method includes:

[0114] Step S301: Make a gradient refractive index lens 30. The gradient refractive index lens 30 can be made of Figure 5 The steps S101 to S105 can be obtained by Figure 16 It is obtained by steps S201 to S203.

[0115] Step S302: Transfer the gradient refractive index lens 30 onto the semiconductor substrate 10 and place it on the side of the cover layer away from the optical waveguide 20; along the direction perpendicular to the plane of the semiconductor substrate 10, the first end of the gradient refractive index lens 30 partially overlaps with the optical waveguide 20.

[0116] use Figure 20The fabrication method provided in this embodiment enables the integration of a separately fabricated gradient index lens 30 into a semiconductor device, enabling evanescent wave coupling between the gradient index lens 30 and an optical waveguide. This reduces the complexity of semiconductor device fabrication, lowers costs, and increases manufacturability. Furthermore, for different products, only a location for the gradient index lens 30 needs to be reserved on the semiconductor substrate 10, increasing packaging flexibility.

[0117] In other embodiments, Figure 21 This is another schematic diagram of a semiconductor device provided in an embodiment of the present application. Figure 21 As shown, the cover layer 40 includes a second groove 52; along a direction e perpendicular to the plane of the semiconductor substrate 10, the depth of the second groove 52 is less than the thickness of the cover layer 40; and at least a portion of the gradient index lens 30 is located within the second groove 52. When the cover layer 40 is thicker, the second groove 52 can be first formed in the cover layer 40, and then the gradient index lens 30 can be transferred into the second groove 52 to couple with the optical waveguide 20 to ensure evanescent wave coupling efficiency.

[0118] In one embodiment, Figure 22 A schematic diagram of another semiconductor device provided in an embodiment of the present application is shown. Figure 22 Schematic diagram of a top view of a semiconductor device. Figure 22 As shown, the first end of the gradient index lens 30 in the first direction a is coupled to the optical waveguide 20. The gradient index lens 30 has a rectangular and tapered shape. The width of the optical waveguide 20 gradually decreases as it approaches the gradient index lens 30, and the tip of the optical waveguide 20 is coupled to the gradient index lens 30. The tip width of the optical waveguide 20 is d1, and the width of the first end of the gradient index lens 30 is d2. Figure 22 In the figure, the second direction b is perpendicular to the first direction a. The tip of the optical waveguide 20 has a width d1 along the second direction b, and the first end of the gradient index lens 30 has a width d2 along the second direction b. Here, d1 is smaller than d2. The rectangular portion of the gradient index lens 30 has a width d3, which is greater than d2. In one embodiment, d3 = 12 μm, d2 = 3 μm, and d1 = 0.31 μm.

[0119] Figure 23 A simulation test diagram of a semiconductor device provided in an embodiment of the present application is shown. Figure 23 The abscissa represents the tip width d1 of the optical waveguide 20 , and the ordinate represents the coupling efficiency between the optical waveguide 20 and the gradient index lens 30 . Figure 23 Schematic diagram showing the variation of coupling efficiency with the tip width d1 of the optical waveguide 20. Figure 23It can be seen that when the parameters of the gradient refractive index lens 30 are determined, as the tip width d1 of the optical waveguide 20 gradually increases, the coupling efficiency between the two increases first and then decreases. When d1≈0.31μm, the optimal coupling efficiency can be achieved at about 79%.

[0120] The gradient refractive index lens 30 and the optical waveguide 20 in the semiconductor device provided in the embodiment of the present application may also have other shapes. The following only uses several optional shapes as examples.

[0121] In one embodiment, Figure 24 Another top view of a semiconductor device provided in an embodiment of the present application is shown in FIG. Figure 24 As shown, the gradient index lens 30 is rectangular in shape, the optical waveguide 20 is tapered and rectangular in shape, and the portion of the optical waveguide 20 corresponding to the gradient index lens 30 is tapered.

[0122] In another embodiment, Figure 25 Another top view of a semiconductor device provided in an embodiment of the present application is shown in FIG. Figure 25 As shown, the gradient index lens 30 is conical, the optical waveguide 20 is conical+rectangular, and the portion of the optical waveguide 20 corresponding to the gradient index lens 30 is conical.

[0123] In another embodiment, Figure 26 Another top view of a semiconductor device provided in an embodiment of the present application is shown in FIG. Figure 26 As shown, the gradient index lens 30 has a rectangular+conical shape, the optical waveguide 20 has a rectangular shape, and the portion of the gradient index lens 30 corresponding to the optical waveguide 20 has a conical shape.

[0124] Figure 22 ,as well as Figures 24 to 26 The semiconductor device provided in the above embodiment adopts Figure 5 When the manufacturing method provided in the embodiment is used for manufacturing, Figure 22 ,as well as Figures 24 to 26 The shape of the main body of the gradient refractive index lens 30 is shown schematically. The gradient refractive index lens 30 also includes a convex portion. The configuration of the convex portion can be referred to. Figure 3 Embodiments for understanding.

[0125] Figure 22 ,as well as Figures 24 to 26 The semiconductor device provided in the embodiment can also be used Figure 16 The manufacturing method provided in the embodiment is used for manufacturing.

[0126] Figure 27 This is a schematic diagram of an application of a semiconductor device provided in an embodiment of the present application. Figure 27As shown, semiconductor device 100 is coupled to optical fiber 200, wherein one end of gradient index lens 30 is coupled to optical waveguide 20, and the other end is coupled to optical fiber 200. Light transmission can be from semiconductor device 100 to optical fiber 200. Light emitted from optical waveguide 20 enters gradient index lens 30, and after being acted upon by multiple refractive layers 301, forms a large light spot. The large light spot emitted by gradient index lens 02 is then coupled to optical fiber 200, thereby matching the light spot of semiconductor device 100 with the light spot of optical fiber 200, reducing optical loss and improving coupling efficiency. Light transmission can also be from optical fiber 200 to semiconductor device 100. That is, light from optical fiber 200 enters gradient index lens 30, where the light spot is reduced, and then enters optical waveguide 20. At the coupling point between optical fiber 200 and gradient index lens 30, the light spots of the two are highly matched, reducing optical loss and improving coupling efficiency.

[0127] In one embodiment, the optical fiber 200 is a single-mode optical fiber. The semiconductor device provided in the embodiments of the present application can be applied to coupling scenarios between silicon-based photonic chips and optical fibers, such as access networks, transport networks, data centers, routers, and the like.

[0128] Based on the same inventive concept, an embodiment of the present application further provides a communication device, which includes the semiconductor device provided by any embodiment of the present application. The structure of the semiconductor device has been described in the above embodiments and will not be repeated here.

Claims

1. A semiconductor device, characterized in that: The semiconductor device includes a semiconductor substrate, an optical waveguide located on one side of the semiconductor substrate, and a gradient refractive index lens; the gradient refractive index lens includes multiple refractive layers, and the multiple refractive layers are stacked in a direction perpendicular to the plane of the semiconductor substrate; the refractive index of the multiple refractive layers gradually decreases along the direction of the gradient refractive index lens away from the semiconductor substrate; the gradient refractive index lens includes a first end in a first direction, and the first end is coupled to the optical waveguide.

2. The semiconductor device according to claim 1, wherein The gradient refractive index lens has at least one irregular area on a side surface in a second direction, the second direction intersects the first direction, and both the first direction and the second direction are parallel to the plane where the semiconductor substrate is located.

3. The semiconductor device according to claim 2, wherein: The gradient refractive index lens includes a main body and at least one protruding portion, the main body includes the first end, the protruding portion is connected to the main body and protrudes outward along the second direction, and the end surface of the protruding portion away from the main body along the second direction includes the irregular area.

4. The semiconductor device according to claim 3, wherein Along a direction perpendicular to the plane of the semiconductor substrate, the thickness of the protruding portion is D1, and the thickness of the main body portion is D2; wherein D1≤D2.

5. The semiconductor device according to claim 3, wherein Both sides of the main body in the second direction are respectively connected to at least one of the protruding parts. The semiconductor device according to claim 1 , wherein: The gradient refractive index lens further includes a substrate, which is located on a side of the plurality of refractive layers away from the semiconductor base.

7. The semiconductor device according to any one of claims 1 to 6, wherein: The semiconductor device has a first groove; along a direction perpendicular to the plane where the semiconductor substrate is located, the first groove penetrates a portion of the film layer of the semiconductor device; At least a portion of the gradient index lens is located in the first groove; The first groove includes a first sidewall, the first sidewall exposes an end face of the optical waveguide, and the end face exposed by the first sidewall is a first end face; in the first groove: the first end is opposite to the first end face.

8. The semiconductor device according to claim 7, wherein: The bottom surface of the gradient refractive index lens close to the semiconductor substrate is a first bottom surface, the end of the first end surface close to the semiconductor substrate is a first bottom end, and the first bottom surface is aligned with the first bottom end.

9. The semiconductor device according to any one of claims 1 to 6, wherein: The semiconductor device includes a covering layer, the covering layer is located on a side of the optical waveguide away from the semiconductor substrate, and the gradient refractive index lens is located on a side of the covering layer away from the optical waveguide; The first end of the gradient index lens partially overlaps the optical waveguide in a direction perpendicular to the semiconductor substrate.

10. The semiconductor device according to claim 9, wherein The cover layer includes a second groove; along a direction perpendicular to the plane where the semiconductor substrate is located, the depth of the second groove is less than the thickness of the cover layer; at least a portion of the gradient refractive index lens is located in the second groove.

11. The semiconductor device according to claim 1, wherein The material of the plurality of refractive layers includes silicon oxynitride.

12. A method for manufacturing a semiconductor device, characterized in that: The production method comprises: Providing a semiconductor substrate, wherein an optical waveguide is formed on one side of the semiconductor substrate; A gradient refractive index lens is transferred to one side of the semiconductor substrate. The gradient refractive index lens includes a first end in a first direction, and the first end is configured to be coupled to the optical waveguide. The gradient refractive index lens includes a plurality of refractive layers, which are stacked in a direction perpendicular to the plane of the semiconductor substrate. The refractive index of the plurality of refractive layers gradually decreases as the gradient refractive index lens moves away from the semiconductor substrate.

13. The manufacturing method according to claim 12, characterized in that: Before transferring the gradient refractive index lens to one side of the semiconductor substrate, the manufacturing method further includes: manufacturing the gradient refractive index lens; wherein, the manufacturing method includes: forming a sacrificial layer pattern on the first substrate; forming a plurality of functional film layers with gradually changing refractive indices on a side of the sacrificial layer pattern away from the first substrate; Performing patterning on the plurality of functional film layers to form a first pattern, the first pattern including a peripheral portion, a central portion, and a connecting portion, the peripheral portion surrounding the sacrificial layer pattern, the central portion and the connecting portion being located above the sacrificial layer pattern, and the connecting portion connecting the central portion and the peripheral portion; removing the sacrificial layer pattern so that the central portion and the connecting portion are suspended; Picking up the central portion from the first substrate to obtain the gradient refractive index lens, wherein the connecting portion is broken to form an irregular cross-section when picking up the central portion, and the plurality of functional film layers form the plurality of refractive layers of the gradient refractive index lens; Transferring the gradient refractive index lens to one side of the semiconductor substrate includes: the gradient refractive index lens has at least one irregular area on a side surface in a second direction, the irregular end surface is the irregular area, the second direction intersects the first direction, and the first direction and the second direction are both parallel to the plane where the semiconductor substrate is located.

14. The manufacturing method according to claim 13, characterized in that: Picking up the central portion from the first substrate to obtain the gradient refractive index lens, comprising: connecting the broken connecting portion and the central portion to form the gradient refractive index lens, wherein the central portion is the main body of the gradient refractive index lens, and the broken connecting portion is the protruding portion of the gradient refractive index lens; Transferring the gradient refractive index lens to one side of the semiconductor substrate, comprising: the main body of the gradient refractive index lens includes the first end, and the protruding portion is connected to the main body and protrudes outward along the second direction; The gradient refractive index lens has at least one irregular area on the side surface in the second direction, including: the end surface of the protrusion away from the main body along the second direction includes the irregular area.

15. The manufacturing method according to claim 12, characterized in that: Before transferring the gradient refractive index lens to one side of the semiconductor substrate, the manufacturing method further includes: manufacturing the gradient refractive index lens; wherein, the manufacturing method includes: forming a plurality of functional film layers on the second substrate; Cutting the second substrate and the plurality of functional film layers to form the gradient refractive index lens, wherein the plurality of functional film layers form a plurality of refractive layers, and the second substrate forms a substrate; Transferring the gradient refractive index lens to one side of the semiconductor substrate comprises: transferring the gradient refractive index lens onto the semiconductor substrate using a flip-chip process, wherein the substrate is located on a side of the plurality of refractive layers away from the semiconductor substrate; the gradient refractive index lens comprises a first end in a first direction, and the first end is configured to be coupled to the optical waveguide.

16. The production method according to any one of claims 12 to 15, characterized in that: Before transferring the gradient refractive index lens to one side of the semiconductor substrate, the manufacturing method further includes: forming a first groove on the semiconductor substrate that penetrates a portion of the film layer; the first groove includes a first sidewall, the first sidewall exposes an end face of the optical waveguide, and the end face exposed by the first sidewall is a first end face; Transferring the gradient refractive index lens to one side of the semiconductor substrate includes: placing at least a portion of the gradient refractive index lens in the first groove, and making the first end face opposite to the first end surface.

17. The production method according to any one of claims 12 to 15, characterized in that: The semiconductor device includes a cover layer, wherein the cover layer is located on a side of the optical waveguide away from the semiconductor substrate; Transferring the gradient refractive index lens to one side of the semiconductor substrate comprises: placing the gradient refractive index lens on a side of the cover layer away from the optical waveguide; Along a direction perpendicular to a plane where the semiconductor substrate is located, the first end partially overlaps with the optical waveguide.

18. A communication device, characterized in that: The communication device includes the semiconductor device according to any one of claims 1 to 11.

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