Packaging structure and forming method thereof

Abstract

The embodiment of the invention provides a packaging structure and a forming method thereof. The packaging structure comprises an interposer and a first optical device, and the interposer comprises a first surface and a second surface which are opposite to each other along a first direction; the first optical device is positioned on the first surface of the intermediate layer and is used for outputting a first optical signal transmitted along the first direction; the interposer is provided with an optical path transmitting along the first direction; the optical path is used for carrying out at least one time of beam shaping on the first optical signal and then generating a target optical signal; the first direction substantially intersects a surface of the first optical device.

Description

Technical Field

[0001] The present disclosure relates to the field of semiconductor technology, and in particular to a packaging structure and a method for forming the same. Background Art

[0002] With the advent of the big data era, the scale of data centers and the amount of data transmission are increasing day by day. Due to the advantages of high speed and low loss of optical communication technology, optical chips have obvious advantages in transmission rate compared with electrical chips.

[0003] In the related art, when the optical chips in the packaging structure are optically interconnected on the horizontal optical path, an off-chip waveguide structure is required for optical routing, which increases the complexity of the device; therefore, the optical chips can be optically interconnected on the vertical optical path to reduce the complexity of the device. However, the solution of optical interconnection on the vertical optical path has problems such as difficulty in optical signal alignment and low coupling efficiency. Summary of the invention

[0004] Embodiments of the present disclosure provide a packaging structure and a method for forming the same.

[0005] In a first aspect, an embodiment of the present disclosure provides a packaging structure, the packaging structure comprising: an interposer and a first optical device, the interposer comprising a first surface and a second surface opposite to each other along a first direction;

[0006] The first optical device is located on the first surface of the intermediary layer and is used to output a first optical signal transmitted along the first direction;

[0007] The intermediate layer has an optical path for transmission along the first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal;

[0008] The first direction substantially intersects a surface of the first optical device.

[0009] In some embodiments, the packaging structure further includes: a second optical device;

[0010] The second optical device is located on the second surface of the intermediate layer, and is used to receive and process the target optical signal.

[0011] In some embodiments, the interposer includes: N sub-interposers stacked along the first direction;

[0012] Each of the sub-intermediation layers comprises an optical device located on the optical path of the first optical signal; the optical device is used to perform the beam shaping on the passing first optical signal;

[0013] The optical paths in N optical devices constitute the optical path, and N is an integer greater than or equal to 1.

[0014] In some embodiments, the optical device is an optical lens, and the optical lens includes a reflector, a convex lens, or a concave lens.

[0015] In some embodiments, the material of the sub-intermediation layer is the same as the material of the corresponding optical lens;

[0016] The first surface and the second surface of the sub-intermediation layer respectively extend beyond two surfaces of the corresponding optical lens along the first direction.

[0017] In a second aspect, an embodiment of the present disclosure provides a packaging structure, the packaging structure comprising: an interposer;

[0018] The intermediate layer has an optical path for transmission along a first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal passing through;

[0019] The first direction substantially intersects a surface of the first optical device.

[0020] In some embodiments, the interposer includes: N sub-interposers stacked along a first direction;

[0021] Each of the sub-intermediation layers comprises an optical device; the optical device is used to perform the beam shaping on the first optical signal passing therethrough;

[0022] The optical paths in N optical devices constitute the optical path, and N is an integer greater than or equal to 1.

[0023] In a third aspect, an embodiment of the present disclosure provides a method for forming a package structure, the method comprising:

[0024] Providing a first optical device; the first optical device is used to output a first optical signal transmitted along a first direction;

[0025] forming an interposer having an optical path transmitting along the first direction;

[0026] The first optical device is bonded to the first surface of the interposer; wherein the first optical signal is subjected to at least one beam shaping through the optical path to generate a target optical signal;

[0027] The first direction intersects a surface of the first optical device.

[0028] In some embodiments, the method further comprises:

[0029] providing a secondary optic;

[0030] The second optical device is bonded to the second surface of the intermediate layer; wherein the second optical device is used to receive and process the target optical signal.

[0031] In some embodiments, forming an interposer includes:

[0032] Forming N sub-intermediation layers; each of the sub-intermediation layers comprises an optical device, and the optical device is used to perform the beam shaping on the first optical signal passing therethrough;

[0033] N sub-intermediation layers are stacked in sequence along the first direction; the optical paths in the N optical devices constitute the optical path, where N is an integer greater than or equal to 1.

[0034] In some embodiments, the optical device is an optical lens; forming a sub-intermediation layer includes:

[0035] Provide an initial sub-intermediation layer;

[0036] The initial sub-interlayer is etched to form the sub-interlayer and at least one etched groove, wherein the sub-interlayer within the at least one etched groove projected along the first direction constitutes the optical lens; wherein the optical lens comprises a reflector, a convex lens or a concave lens.

[0037] In some embodiments, the optical lens includes at least one optical interface formed by the following steps:

[0038] forming a first mask layer having a first pattern on the surface of the initial sub-interposer; the bottom of the first pattern is a curved surface or a flat surface;

[0039] The initial sub-interlayer is etched through the first mask layer to remove the exposed portion of the initial sub-interlayer to form the etched groove; the curved surface or the flat surface at the bottom of the etched groove constitutes the optical interface.

[0040] The disclosed embodiment provides a packaging structure and a method for forming the same, the packaging structure comprising: an intermediary layer and a first optical device, the intermediary layer comprising a first surface and a second surface opposite to each other along a first direction; the first optical device is located on the first surface of the intermediary layer and is used to output a first optical signal transmitted along the first direction; the intermediary layer has an optical path transmitted along the first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal; the first direction intersects with the surface of the first optical device. Here, since the intermediary layer has an optical path transmitted along the first direction, the optical path can be used to perform beam shaping on the first optical signal during its transmission, thereby adjusting the shape, angle, size, and intensity of the first optical signal, so that the generated target optical signal is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In the accompanying drawings (which are not necessarily drawn to scale), like reference numerals may describe similar components in different views. Like reference numerals with different letter suffixes may represent different examples of similar components. The accompanying drawings generally illustrate various embodiments discussed herein by way of example and not limitation.

[0042] Figure 1 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 1 ;

[0043] Figure 2 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 2 ;

[0044] Figure 3 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 3 ;

[0045] Figure 4 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 4 ;

[0046] Figure 5 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 5 ;

[0047] Figure 6 A schematic diagram of a packaging structure provided in an embodiment of the present disclosure Figure 6 ;

[0048] Figure 7 A schematic diagram of another packaging structure provided in an embodiment of the present disclosure Figure 1 ;

[0049] Figure 8 A schematic diagram of another packaging structure provided in an embodiment of the present disclosure Figure 2 ;

[0050] Fig. 9 A schematic diagram of a process for forming a packaging structure provided by an embodiment of the present disclosure;

[0051] Fig.10 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 1 ;

[0052] Fig.11 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 2 ;

[0053] Fig.12 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 3 ;

[0054] Fig.13 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 4 ;

[0055] Fig.14 It is a schematic diagram of the relationship between the transmittance of the mask layer and the thickness of the anti-etching agent after exposure in grayscale etching;

[0056] Fig.15 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 5 ;

[0057] Fig.16 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 6 ;

[0058] Fig.17 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 7 ;

[0059] Fig.18 A schematic diagram of a packaging structure during the formation process provided by an embodiment of the present disclosure Figure 8 . DETAILED DESCRIPTION

[0060] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the specific embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0061] In the following description, a large number of details are given to provide a more thorough understanding of the present disclosure. However, it is obvious to those skilled in the art that the present disclosure can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present disclosure, some technical features known in the art are not described; that is, all features of actual embodiments are not described here, and well-known functions and structures are not described in detail.

[0062] In the drawings, the sizes of layers, regions, elements and their relative sizes may be exaggerated for clarity. Like reference numerals denote like elements throughout.

[0063] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not indicate that the present disclosure necessarily has the first element, component, region, layer or part.

[0064] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present disclosure. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0065] With the advent of the big data era, the amount of data transmitted in optical communications such as data centers is increasing day by day. To meet this challenge, optoelectronic advanced packaging can be used to increase the functional density of chips, reduce the size of products, and enhance the efficiency of optoelectronic interconnection.

[0066] Furthermore, in a 2.5D or 3D optoelectronic packaging structure, the metal interconnection between the optical chip and the electrical chip in the vertical direction can be achieved through silicon via (TSV) technology, but the optical interconnection in the vertical direction is difficult to achieve. In the related art, since the solution of optical coupling through the horizontal optical path (i.e., the horizontal direction) can only be performed at the edge of the chip, when the optical signal enters the multi-core optical fiber or multi-fiber optical cable, it is necessary to route the optical signal through an off-chip waveguide structure, which increases the complexity of the device (i.e., the optoelectronic packaging structure). The solution of optical coupling on the vertical optical path requires mode field matching for the interconnection between chips. Therefore, it is necessary to consider the vertical optical interconnection solution that considers both the path selection of light and the mode field matching of light.

[0067] Based on this, the embodiment of the present disclosure provides a packaging structure and a method for forming the same, wherein the packaging structure includes: an interposer, and a first optical device located on a first surface of the interposer; the first optical device is used to output a first optical signal transmitted along a first direction; the interposer has an optical path transmitted along the first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal. Here, since the interposer has an optical path transmitted along the first direction, the optical path can be used to perform beam shaping on the first optical signal during its transmission, thereby adjusting the shape, angle, size, and intensity of the first optical signal, so that the generated target optical signal is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal.

[0068] Before introducing the embodiments of the present disclosure, two directions that may be used in the following embodiments to describe the three-dimensional structure are defined. The direction intersecting (e.g., perpendicular) to the surface of the first optical device is defined as the first direction, and the direction parallel to the surface of the first optical device is defined as the second direction. In the embodiments of the present disclosure, the first direction is defined as the X-axis direction, and the second direction is defined as the Y-axis direction.

[0069] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0070] In one embodiment of the present disclosure, see Figure 1 , which shows a schematic diagram of the composition structure of a packaging structure 100 provided by an embodiment of the present disclosure. Figure 1 As shown, the packaging structure 100 includes: an intermediate layer 120, and a first optical device 110 located on the first surface of the intermediate layer 120; the first optical device 110 is used to output a first optical signal transmitted along the X-axis direction; the intermediate layer 120 has an optical path 130 transmitted along the X-axis direction; the optical path 130 is used to generate a target optical signal after performing at least one beam shaping on the first optical signal.

[0071] Here, the first surface of the interposer 120 refers to a surface on one side of the interposer along the X-axis direction; similarly, the second surface of the interposer 120 refers to a surface on the other side of the interposer along the X-axis direction.

[0072] In the embodiment of the present disclosure, the first optical device 110 may be any device that can output the first optical signal, such as an optical chip or an optical fiber coupler. Here, the optical chip may include a silicon photonic chip, an optical transmitting chip (such as a laser chip), etc.

[0073] For example, when the packaging structure 100 is located at the transmitting end, the first optical device 110 can be a fiber coupler or an optical transmitting chip, and the first optical signal is output to the intermediate layer 120 through the first optical device 110; specifically, the first optical signal output by the first optical device 110 can be formed by the following steps: first, the signal is collected, and the analog signals such as sound and image are converted into electrical signals through sensors (such as microphones, cameras, etc.); next, the electrical signal is processed by the optical chip, and the electrical signal is converted into a form suitable for optical signal transmission, such as by changing the intensity, frequency or phase of the optical signal to encode information, thereby generating a first optical signal.

[0074] For another example, when the packaging structure 100 is located at the receiving end, the first optical device 110 can be any device with an optical IO (input-output) structure, such as an optical fiber coupler, an optical transmitting chip, etc. The first optical device 110 can receive a signal output by an off-chip transmitting device, and the signal can be exported / converted into a first optical signal and then output to the intermediate layer 120.

[0075] In the embodiment of the present disclosure, the projections of the input end and the output end of the optical path 130 on the Y axis overlap, so that the first optical signal can be transmitted along a straight line, thereby reducing the transmission path of the first optical signal, and further reducing the energy loss of the first optical signal during the beam shaping process. Alternatively, the projections of the input end and the output end of the optical path 130 on the Y axis do not overlap; for example, the first optical signal can be reflected by the optical path 130, thereby changing the position of the output end of the optical path 130, so that the various devices in the packaging structure can be flexibly designed and laid out, broadening the application scenarios of the wiring of the packaging structure.

[0076] It should be noted that, in order to facilitate the explanation of the direction and path of the first optical signal, the present disclosure takes the transmission of the first optical signal output by the first optical device 110 along the X-axis direction as an example; in fact, the first optical signal is not necessarily transmitted completely along the X-axis direction, and there may be a certain angle offset.

[0077] In the embodiment of the present disclosure, the optical path 130 is composed of any one or more optical devices that can realize beam shaping; wherein the optical device can be an optical lens, a mask or a grating. In addition, beam shaping can include reflection, beam collimation, beam expansion, beam combination and diffraction, etc.

[0078] In the embodiment of the present disclosure, the optical device in the optical pathway 130 may be made of any suitable material, such as glass (i.e., silicon dioxide), polymer, or other transparent materials. The material of the intermediary layer 120 may be any suitable insulating material; for example, the material of the intermediary layer 120 may be the same as the material of the optical pathway 130, so that the optical pathway 130 may be formed directly on the intermediary layer 120, reducing the complexity of forming the optical pathway 130. In other embodiments, the material of the intermediary layer 120 may also be different from the material of the optical pathway 130, for example, the material of the intermediary layer 120 may be silicon nitride.

[0079] In the disclosed embodiment, the optical path 130 can be used to perform beam shaping on the first optical signal while achieving optical interconnection, so that the shape, angle, size and intensity of the first optical signal can be adjusted, so that the generated target optical signal (i.e., the first optical signal after beam shaping) is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal.

[0080] In some embodiments, please refer to Figure 2 and Figure 3 The packaging structure 100 further includes: a second optical device 150; the second optical device 150 is located on the second surface of the intermediate layer 120 and is used to receive and process the target optical signal.

[0081] In the disclosed embodiment, the second optical device 150 may be any device that can receive and process the target optical signal, such as an optical chip or an optical fiber coupler. Here, the optical chip may include a silicon photonic chip, an optical receiving chip (such as a detector chip), etc.

[0082] For example, see Figure 2 When the packaging structure 100 is located at the transmitting end, the second optical device 150 can be any device with an optical IO (input and output) structure, such as an optical fiber coupler, an optical receiving chip, etc. The target optical signal can be exported to an off-chip receiving device or optical signal processing can be performed through the second optical device 150.

[0083] For example, please refer to Figure 3 When the packaging structure 100 is located at the receiving end, the second optical device 150 can be a fiber coupler or an optical receiving chip, and the target optical signal can be received and processed through the second optical device 150.

[0084] In summary, the difference between the package structure 100 being located at the transmitting end and the receiving end is that when the package structure 100 is located at the transmitting end, the second optical device 150 is a device with an optical IO structure; for example, please refer to Figure 2 , the first optical device 110 may be an optical chip, and the second optical device 150 may be a device with an optical IO structure (fiber coupler, detector chip or other optical chip with an optical receiving end). In this way, the first optical device 110 may send out a first optical signal, and after the interposer 120 optically shapes the first optical signal, the second optical device 150 receives the target optical signal and then exports or processes the optical signal. When the package structure 100 is located at the receiving end, the first optical device 110 is a device with an optical IO structure; for example, please refer to Figure 3 The first optical device 110 can be a device with an optical IO structure (fiber coupler, laser chip or other optical chip with an optical emitting end), and the second optical device 150 can be an optical chip. In this way, the first optical signal output by the off-chip emitting device can be received by the first optical device 110, and after the first optical signal is optically shaped by the intermediate layer 120, the target optical signal is processed by the second optical device 150.

[0085] In addition, the optical chip includes a silicon substrate and an optical device integrated on the first surface of the silicon substrate; wherein the optical device includes an input interface and an output interface. When the package structure 100 is located at the transmitting end, please refer to Figure 2 , the optical chip (i.e., the first optical device 110) outputs the first optical signal along the X-axis direction through the output interface 111; the output interface 111 may be an optical fan-out device, such as a grating coupler (GC), etc. When the package structure 100 is located at the receiving end, please refer to Figure 3 , the optical chip (i.e., the second optical device 150) receives the target optical signal transmitted along the X-axis direction through the input interface 151; the input interface 151 can be an optical fan-in device, such as a grating coupler. Since the optical signal is transmitted along the X-axis direction, it is beneficial for the optoelectronic chips to be stacked closely in the vertical direction, thereby improving the flexibility and scalability of the packaging design. Furthermore, the optical device can also include light sources, modulators, detectors, passive waveguide devices, and other parts.

[0086] In the embodiment of the present disclosure, by providing the second optical device 150 to receive the target optical signal, on the one hand, the difficulty of aligning the target optical signal is reduced, thereby improving the coupling efficiency of the target optical signal; on the other hand, a higher degree of freedom can be provided for the optical path design.

[0087] In some embodiments, the packaging structure 100 also includes a third optical device 160 located on the first surface or the second surface of the intermediate layer 120; the intermediate layer 120 also includes a through-hole structure 140; the through-hole structure 140 is used to electrically connect the optical chip and the third optical device 160 when the first optical device 110 or the second optical device 150 is an optical chip.

[0088] In the embodiment of the present disclosure, the third optical device 160 can be an electrical chip. The working principle of the electrical chip is to use the changes in current and voltage to transmit and process signals, and its core is an integrated circuit (IC). After the integrated circuit receives signals or instructions from the outside, it parses, processes and makes decisions through the circuits and logic units inside the integrated circuit, and outputs corresponding control signals or data.

[0089] In the embodiment of the present disclosure, the third optical device 160 may be a radio frequency chip (RF Chip), a digital signal processing chip (DSP Chip), an interface chip (Interface Chip), a microcontroller chip (MCU Chip) and the like in an electronic chip.

[0090] In the embodiment of the present disclosure, the package structure 100 may further include: a through-hole structure 140 and an IO pad 170. Figure 2 The third optical device 160 can be located on the second surface of the intermediate layer 120. When the first optical device 110 is an optical chip (for example, a silicon photonic chip, an optical transmitting chip), the third optical device 160 is electrically connected to the first optical device 110 through the through-hole structure 140 to achieve signal transmission and power sharing between the first optical device 110 and the third optical device 160; when the second optical device 150 is an optical chip (for example, a silicon photonic chip, an optical receiving chip), the first optical device 110 is also electrically connected to the second optical device 150 through the through-hole structure 140, so that the second optical device 150 can be powered by the third optical device 160; in this way, the integration and performance of the packaging structure 100 are improved. The through-hole structure 140 cooperates with the redistribution layer to reallocate the IO pads 170 in the first optical device 110 and the third optical device 160 to appropriate positions to adapt to the layout and interface requirements of the packaging structure 100.

[0091] Please refer to Figure 3, the third optical device 160 can be located on the first surface of the interposer 120. When the second optical device 150 is an optical chip, the third optical device 160 is electrically connected to the second optical device 150 through the through-hole structure 140, so as to realize signal transmission and power sharing between the second optical device 150 and the third optical device 160; when the first optical device 110 is an optical chip, the first optical device 110 is also electrically connected to the second optical device 150 through the through-hole structure 140, so that the first optical device 110 can be powered by the third optical device 160; in this way, the integration and performance of the packaging structure 100 are improved. In addition, the through-hole structure 140 can also be combined with the redistribution layer to reallocate the IO pads 170 in the second optical device 150 and the third optical device 160 to a suitable position to adapt to the layout and interface requirements of the packaging structure 100.

[0092] It should be noted that when the first optical device 110 (or the second optical device 150) is a non-optical chip (for example, an optical fiber, an optical fiber array, an optical fiber coupler, etc.), it is not necessary to set the through-hole structure 140 and the IO pad 170 to electrically connect the first optical device 110 (or the second optical device 150).

[0093] It should also be noted that the relative arrangement of the electrical chip (i.e., the third optical device 160) and the optical chip (i.e., the first optical device 110 or the second optical device 150) can improve the functional density of the chip and help reduce the volume of the packaging structure. In other embodiments, the electrical chip (i.e., the third optical device 160) and the optical chip (i.e., the first optical device 110 or the second optical device 150) can also be arranged on the same side of the interposer 120.

[0094] In the disclosed embodiment, the through-hole structure 140 is composed of a plurality of through-holes (five are shown in the figure); the through-hole structure 140 (or a plurality of through-holes) may be composed of any suitable conductive metal material, such as copper, aluminum, copper-aluminum alloy or tungsten.

[0095] Finally, please refer to Figures 4 to 6 , the packaging structure 100 is described in detail; wherein, Figure 4 and Figure 5 for Figure 2 Two structural schematic diagrams of the packaging structure 100 are shown; Figure 6 for Figure 3 The detailed structural diagram of the packaging structure 100 is shown.

[0096] In some embodiments, please refer to Figures 4 to 6The intermediary layer 120 includes: N sub-intermediary layers 121 stacked along the X-axis direction; each sub-intermediary layer 121 includes an optical device 131 located on the optical path of the first optical signal; the optical device 131 is used to perform beam shaping on the passing first optical signal; wherein the optical paths in the N optical devices 131 constitute an optical path 130 (as shown in the dotted line range in the figure), and N is an integer greater than or equal to 1.

[0097] Here, since each sub-intermediary layer 121 includes an optical device 131, the number of layers of the sub-intermediary layer 121 (i.e., the value of N) can be set according to the number of times the first optical signal needs to be beam shaped. For example, when the first optical signal needs to be beam shaped three times, the sub-intermediary layer 121 can be set to 3 layers, so that the first optical signal is beam shaped by the optical device 131 in each sub-intermediary layer 121 in turn to generate a target optical signal. For another example, please refer to Figures 4 to 6 When the first optical signal needs to be beam shaped four times, the sub-intermediation layer 121 can be set to 4 layers, so that the first optical signal is beam shaped by the optical device 131 in each sub-intermediation layer 121 in turn to generate a target optical signal.

[0098] In this disclosure, please continue to refer to Figures 4 to 6 Each sub-interposer 121 further includes a sub-through hole structure 141 located on one side of the optical device 131, and each sub-through hole structure includes a plurality of sub-through holes (5 are shown in the figure). The sub-through hole structures 141 in each sub-interposer 121 are connected to form a through hole structure 140; for example, Figures 4 to 6 In the figure, the sub-via structures 141 - 1 to 141 - 4 are connected to form the via structure 140 .

[0099] In some embodiments, the optical device 131 is an optical lens, and the types of the optical lens include a reflector, a convex lens, or a concave lens.

[0100] Here, beam shaping includes reflection, beam collimation, beam expansion, beam combination and diffraction, etc. The first optical signal can be reflected by a reflector to change the transmission direction of the first optical signal. The convex lens includes a biconvex lens, a plano-convex lens, a concave-convex lens, etc.; the first optical signal can be focused by the convex lens. The concave lens includes a biconcave lens, a plano-concave lens, a convex-concave lens, etc., and the first optical signal can be diverged by the concave lens.

[0101] In the embodiment of the present disclosure, the type of optical lens can be set according to actual needs. For example, please refer to Figure 4 and Figure 6, the optical device 131 is composed of a plano-convex lens, a convex-concave lens, and two convex lenses from bottom to top; here, the plano-convex lens can focus the first light signal, the convex-concave lens and the adjacent convex lens can collimate the first light signal, and the last convex lens can focus the first light signal; in this way, the target light signal generated after multiple focusing and collimation of the first light signal can better match the mode field with the second optical device 150.

[0102] For example, please refer to Figure 5 , the optical device 131 is a reflector, a plano-convex lens, a convex-concave lens and a convex lens from bottom to top; here, the reflector can change the transmission path of the first optical signal, so as to facilitate the optical interconnection between the first optical device 110 and the second optical device 150, the plano-convex lens can focus the first optical signal, and the convex-concave lens and the adjacent convex lens can collimate the first optical signal; in this way, the target optical signal generated after reflecting, focusing and collimating the first optical signal can better match the mode field with the second optical device 150.

[0103] It should be noted that in the embodiment of the present disclosure, the first light signal is beam shaped by an optical lens. In some other embodiments, the optical device 131 may also be a mask or a grating; thus, masks with different apertures may be selected to control the shape and size of the first light signal, or the phase and amplitude of the first light signal may be adjusted by a grating.

[0104] In some embodiments, the material of the sub-intermediate layer 121 is the same as the material of the corresponding optical lens (ie, the optical device 131). Here, the sub-intermediate layer 121 and the optical lens can be made of any suitable material, for example, glass (ie, silicon dioxide), polymer or other transparent materials.

[0105] In the embodiment of the present disclosure, since the material of the sub-intermediate layer 121 is the same as that of the corresponding optical lens, not only the thermal expansion coefficients of the sub-intermediate layer 121 and the optical lens are closer, which helps to reduce the stress differences caused by temperature changes, thereby improving the stability of the entire optical system; it can also reduce the processing difficulty and cost of the sub-intermediate layer 121 and the corresponding optical lens, while improving the processing accuracy.

[0106] In some embodiments, the first surface and the second surface of the sub-intermediate layer 121 respectively extend beyond the two surfaces of the corresponding optical lens along the X-axis direction. For example, the top surface and the bottom surface of the sub-intermediate layer 121 respectively extend beyond the top and the bottom of the corresponding optical lens. In this way, during the packaging process, the first surface and the second surface of the sub-intermediate layer 121 can be used as positioning references or bonding surfaces to improve the accuracy and efficiency of packaging; at the same time, the first optical signal can enter the optical lens from the air, thereby refracting the first optical signal.

[0107] In the disclosed embodiment, the optical path 130 is composed of at least one optical device 131, and the first optical signal is beam-shaped by the at least one optical device 131. The shape, angle, size and intensity of the first optical signal can be adjusted while realizing optical interconnection, so that the generated target optical signal (i.e., the first optical signal after beam shaping) is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal.

[0108] The present disclosure also provides another packaging structure 200. Figure 7 and Figure 8 The packaging structure 200 includes: an interposer 210; the interposer 210 has an optical path 220 transmitting along the X-axis direction; the optical path 220 is used to generate a target optical signal after performing at least one beam shaping on the first optical signal passing through. In this way, optical interconnection can be achieved through the interposer 210.

[0109] In some embodiments, please refer to Figure 7 and Figure 8 The intermediary layer 210 includes: N sub-intermediary layers 211 stacked along the X-axis direction; each sub-intermediary layer 211 includes an optical device 221; the optical device 221 is used to perform beam shaping on the first optical signal passing through; wherein, the optical path in the N optical devices 221 constitutes an optical path 220, and N is an integer greater than or equal to 1.

[0110] Here, since each sub-intermediation layer 211 includes an optical device 221, the number of layers of the sub-intermediation layer 211 (ie, the value of N) can be set according to the number of times the first optical signal needs to be beam shaped. Figure 8 When the first optical signal needs to be beam shaped four times, the sub-intermediation layer 211 can be set to 4 layers, so that the first optical signal is beam shaped by the optical device 221 in each sub-intermediation layer 211 in turn to generate a target optical signal.

[0111] In some embodiments, the optical device 221 is an optical lens, and the types of the optical lens include a reflector, a convex lens, or a concave lens.

[0112] Here, beam shaping includes reflection, beam collimation, beam expansion, beam combination and diffraction, etc. The first optical signal can be reflected by a reflector to change the transmission direction of the first optical signal. The convex lens includes a biconvex lens, a plano-convex lens, a concave-convex lens, etc.; the first optical signal can be focused by the convex lens. The concave lens includes a biconcave lens, a plano-concave lens, a convex-concave lens, etc., and the first optical signal can be diverged by the concave lens.

[0113] In the embodiment of the present disclosure, the type of optical lens can be set according to actual needs. For example, please refer to Figure 8 The optical device 221 includes a reflector, a plano-convex lens, a convex-concave lens and a convex lens from bottom to top.

[0114] It should be noted that in the embodiment of the present disclosure, the first optical signal is beam shaped by an optical lens. In some other embodiments, the optical device 221 may also be a mask or a grating; thus, masks with different apertures may be selected to control the shape and size of the first optical signal, or the phase and amplitude of the first optical signal may be adjusted by a grating.

[0115] In some embodiments, the material of the sub-intermediate layer 211 is the same as the material of the corresponding optical lens (ie, the optical device 221). Here, the sub-intermediate layer 211 and the optical lens can be made of any suitable material, such as glass (ie, silicon dioxide), polymer or other transparent materials.

[0116] In the embodiment of the present disclosure, since the material of the sub-intermediate layer 211 is the same as that of the corresponding optical lens, not only the thermal expansion coefficients of the sub-intermediate layer 211 and the optical lens are closer, which helps to reduce the stress differences caused by temperature changes, thereby improving the stability of the entire optical system; it can also reduce the processing difficulty and cost of the sub-intermediate layer 211 and the corresponding optical lens, while improving the processing accuracy.

[0117] In some embodiments, the first surface and the second surface of the sub-intermediate layer 211 respectively extend beyond the two surfaces of the corresponding optical lens along the X-axis direction. For example, the top surface and the bottom surface of the sub-intermediate layer 211 respectively extend beyond the top and the bottom of the corresponding optical lens. In this way, during the packaging process, the first surface and the second surface of the sub-intermediate layer 211 can be used as positioning references or bonding surfaces to improve the accuracy and efficiency of packaging; at the same time, the first optical signal can enter the optical lens from the air, thereby refracting the first optical signal.

[0118] In the disclosed embodiment, the optical path 220 is composed of at least one optical device 221, and the first optical signal is beam-shaped by the at least one optical device 221. The shape, angle, size and intensity of the first optical signal can be adjusted while realizing optical interconnection, so that the generated target optical signal (i.e., the first optical signal after beam shaping) is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal.

[0119] The intermediary layer in the embodiment of the present disclosure is similar to the intermediary layer in the above-mentioned embodiment. For the technical features not fully disclosed in the embodiment of the present disclosure, please refer to the above-mentioned embodiment for understanding, and no further details will be given here.

[0120] In addition, the present disclosure also provides a method for forming the package structure 100. Fig. 9A schematic diagram of a process for forming a packaging structure provided by an embodiment of the present disclosure, Figures 10 to 18 For the embodiments of the present disclosure, Figure 4 The structure diagram of the packaging structure 100 during the formation process is shown.

[0121] It should be noted that the formation methods of other packaging structures are similar to Figure 4 The packaging structure shown is formed in a similar manner, please refer to Figure 4 The formation method of the packaging structure shown in the figure can be understood and will not be described here.

[0122] In the embodiments of the present disclosure, please refer to Fig. 9 , the method for forming the package structure 100 includes: step S110 to step S130.

[0123] Step S110, providing a first optical device 110; the first optical device 110 is used to output a first optical signal transmitted along the X-axis direction.

[0124] In the embodiment of the present disclosure, the first optical device 110 may be any device that can output the first optical signal, such as an optical chip or an optical fiber coupler; for example, please refer to Fig.10 When the package structure 100 is located at the transmitting end, the first optical device 110 can be an optical chip (such as a laser chip). Further, the optical chip includes a silicon substrate and an optical device integrated on the first surface of the silicon substrate; the optical device includes an output interface 111, and the output interface 111 is used to output the first optical signal output along the X-axis direction. The output interface 111 can be a grating coupler. In addition, the optical device can also include a light source, a modulator, a detector, a passive waveguide device, etc., so that the processing and transmission functions of the optical signal are realized through these optical devices.

[0125] Step S120 , forming an intermediate layer 120 , wherein the intermediate layer 120 has an optical path transmitting along the X-axis direction.

[0126] In some embodiments, step S120, forming the intermediate layer 120, includes: step S120a and step S120b.

[0127] Step S120a, forming N sub-intermediation layers 121; each sub-intermediation layer 121 includes an optical device 131, and the optical device 131 is used to perform beam shaping on the passing first optical signal.

[0128] First, please refer to Fig.11 , providing an initial sub-interspersing layer 121a. The initial sub-interspersing layer 121a includes a first surface A and a second surface B opposite to each other along the X-axis direction. Here, the material of the initial sub-interspersing layer 121a may be glass (ie, silicon dioxide), polymer or other transparent materials.

[0129] Next, please refer to Figures 12 to 17 , etching the initial sub-intermediate layer 121a, forming a sub-intermediate layer 121 and at least one etched groove, wherein the sub-intermediate layer 121 within the at least one etched groove projected along the X-axis direction constitutes an optical device 131; wherein the optical device 131 can be an optical lens, and the optical lens includes a reflector, a convex lens or a concave lens.

[0130] When implementing, take forming a double convex lens as an example, please refer to Fig.12 and Fig.13 A first initial mask layer 180a is formed on the first surface A of the initial sub-interposer 121a. A first mask layer 180 having a first pattern H is formed by grayscale etching the first initial mask layer 180a. The bottom of the first pattern H has a convex curved surface.

[0131] Please refer to Fig.14 , which is a schematic diagram of the relationship between the transmittance of the mask layer and the thickness of the anti-etching agent after exposure in grayscale etching; specifically, as the exposure dose increases to reach the threshold energy (D0), the anti-etching agent (i.e., the mask layer) begins to dissolve, and the thickness of the anti-etching agent changes linearly with the exposure dose; when the exposure dose reaches the cut-off energy (D1), the anti-etching agent is completely dissolved and the thickness is 0. In this way, the first pattern H in the first mask layer can be formed according to the metering of the controlled exposure.

[0132] In addition, the subsequent method for forming a mask layer by grayscale etching is similar to the method for forming the first mask layer, and can be understood according to the method for forming the first mask layer.

[0133] Please refer to Fig.15 , the initial sub-interlayer 121a is etched through the first mask layer 180, and the exposed portion of the initial sub-interlayer 121a is removed to form an etched groove 131a and an intermediate sub-interlayer 121b; the bottom of the etched groove 131a constitutes an optical interface (a convex curved surface). It should be noted that the shape of the etched groove 131a is the same as the shape of the first pattern H.

[0134] Similarly, please refer to Fig.16 A second initial mask layer (not shown) is formed on the second surface B. The second initial mask layer is etched by grayscale to form a second mask layer 181; wherein the second mask layer 181 has a second pattern K, and the bottom of the second pattern K has a convex curved surface.

[0135] Please refer to Fig.17, the middle sub-intermediation layer 121b is etched through the second mask layer 181 to form the sub-intermediation layer 121 and the etching groove 131b; wherein the bottom of the etching groove 131b constitutes an optical interface (a convex curved surface). The part of the sub-intermediation layer 121 within the X-axis projection range constitutes an optical lens (i.e., the optical device 131).

[0136] In the embodiment of the present disclosure, since the sub-intermediate layer 121 and the optical lens (i.e., the optical device 131) are formed by etching the initial sub-intermediate layer 121a, the sub-intermediate layer 121 and the optical lens are made of the same material, which not only makes the thermal expansion coefficients of the sub-intermediate layer 121 and the optical lens closer, which helps to reduce the stress difference caused by temperature changes, thereby improving the stability of the entire optical system; it can also reduce the processing difficulty and cost of the sub-intermediate layer 121 and the corresponding optical lens, while improving the processing accuracy.

[0137] In this disclosure, please continue to refer to Fig.17 The method for forming the sub-interposer 121 further includes: forming a sub-through hole structure 141 located on one side of the optical device 131 along the Y-axis direction. During implementation, a glass through hole (not shown) is formed on one side (e.g., the left side) of the optical device 131 along the Y-axis direction, and any suitable conductive metal is deposited in the glass through hole to form the sub-through hole structure 141. The sub-through hole structure 141 is composed of a plurality of sub-through holes (five are shown in the figure).

[0138] It should be noted that the embodiment of the present disclosure is described by taking the example of first forming the optical device 131 and then forming the sub-through hole structure 141. In other embodiments, the sub-through hole structure 141 may be formed first and then the optical device 131 may be formed.

[0139] In the embodiment of the present disclosure, since the formation of the optical device 131 is compatible with the electrical TGV (through glass via) process, it can support the co-packaging of electrical chips, optical chips, etc.

[0140] In addition, the method for forming other types of optical lenses is similar to the method for forming a biconvex lens described above. Please refer to the method for forming a biconvex lens described above for understanding, and no further description is given here. For example, when forming a biconcave lens, the bottom of the etched groove formed by the first mask layer and the second mask layer is a concave curved surface; for another example, when forming a plano-convex lens, the bottom of the etched groove formed by the first mask layer and the second mask layer is a horizontal plane and a convex curved surface, respectively; for another example, when forming a reflector, the bottom of the etched groove formed by the first mask layer and the second mask layer is an inclined plane. In addition, a reflective material, such as a metal coating, can be deposited on the surface of the reflector to achieve efficient reflection of the first optical signal.

[0141] In the embodiment of the present disclosure, step S120a is performed to form Fig.18 Four sub-interposers 121 are shown.

[0142] Step S120b, stacking N sub-intermediation layers 121 in sequence along the X-axis direction; the optical paths in the N optical devices 131 constitute an optical path, where N is an integer greater than or equal to 1.

[0143] In this disclosure, please continue to refer to Fig.18 , four sub-interposers 121 are stacked in sequence along the X-axis direction. Here, the optical paths in the four optical devices 131 constitute an optical path 130 , and the sub-through hole structures 141 a in the four sub-interposers 121 constitute a through hole structure 140 .

[0144] Step S130 , bonding the first optical device 110 to the first surface of the intermediary layer 120 ; wherein the first optical signal is beam shaped at least once through the optical path to generate a target optical signal.

[0145] In some embodiments, the method for forming the package structure 100 further includes: providing a second optical device 150 ; bonding the second optical device 150 to the second surface of the intermediate layer 120 ; wherein the second optical device 150 is used to receive and process a target optical signal.

[0146] In the embodiment of the present disclosure, the second optical device 150 can be any device such as an optical chip or an optical fiber coupler that can receive and process the target optical signal. Figure 4 When the packaging structure 100 is located at the transmitting end, the second optical device 150 can be any device with an optical IO (input-output) structure, such as a multi-core optical fiber, an optical fiber coupler, etc., through which the target optical signal can be exported to an off-chip receiving device.

[0147] In the embodiment of the present disclosure, the method for forming the package structure 100 further includes: providing a third optical device 160; stacking the third optical device 160 on the surface of the interposer 120, thereby forming Figure 4 The package structure 100 is shown.

[0148] In the embodiment of the present disclosure, the third optical device 160 may be a radio frequency chip (RF Chip), a digital signal processing chip (DSP Chip), an interface chip (Interface Chip), a microcontroller chip (MCU Chip) and the like in an electronic chip.

[0149] In the disclosed embodiment, since an optical path 130 is formed in the intermediate layer 120, the first optical signal can be beam shaped while realizing optical interconnection of optical devices, so that the shape, angle, size and intensity of the first optical signal can be adjusted, so that the generated target optical signal (i.e., the first optical signal after beam shaping) is less difficult to align during optical interconnection, thereby improving the coupling efficiency of the target optical signal.

[0150] In addition, the packaging structure formed in the embodiment of the present disclosure is similar to the packaging structure in the above-mentioned embodiment. For the technical features not fully disclosed in the embodiment of the present disclosure, please refer to the above-mentioned embodiment for understanding, and no further details will be given here.

[0151] In the several embodiments provided in the present disclosure, it should be understood that the disclosed structures and methods can be implemented in a non-targeted manner. The structural embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation, such as: multiple units or devices can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the components shown or discussed are coupled or directly coupled to each other.

[0152] The features disclosed in several method or structural embodiments provided in the present disclosure may be arbitrarily combined without conflict to obtain new method embodiments or structural embodiments.

[0153] The above are only some embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A packaging structure, characterized in that: The packaging structure comprises: an intermediary layer and a first optical device, wherein the intermediary layer comprises a first surface and a second surface opposite to each other along a first direction; The first optical device is located on the first surface of the intermediary layer and is used to output a first optical signal transmitted along the first direction; The intermediate layer has an optical path for transmission along the first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal; The first direction substantially intersects a surface of the first optical device.

2. The packaging structure according to claim 1, characterized in that: The packaging structure further includes: a second optical device; The second optical device is located on the second surface of the intermediate layer, and is used to receive and process the target optical signal.

3. The packaging structure according to claim 1 or 2, characterized in that: The interposer comprises: N sub-interposers stacked along the first direction; Each of the sub-intermediation layers comprises an optical device located on the optical path of the first optical signal; the optical device is used to perform the beam shaping on the passing first optical signal; The optical paths in N optical devices constitute the optical path, and N is an integer greater than or equal to 1.

4. The packaging structure according to claim 3, characterized in that: The optical device is an optical lens, and the optical lens includes a reflector, a convex lens or a concave lens.

5. The packaging structure according to claim 4, characterized in that: The material of the sub-intermediation layer is the same as the material of the corresponding optical lens; The first surface and the second surface of the sub-intermediation layer respectively extend beyond two surfaces of the corresponding optical lens along the first direction.

6. A packaging structure, characterized in that: The packaging structure includes: an interposer; The intermediate layer has an optical path for transmission along a first direction; the optical path is used to generate a target optical signal after performing at least one beam shaping on the first optical signal passing through; The first direction substantially intersects a surface of the first optical device.

7. The packaging structure according to claim 6, characterized in that: The interposer comprises: N sub-interposers stacked along a first direction; Each of the sub-intermediation layers comprises an optical device; the optical device is used to perform the beam shaping on the first optical signal passing therethrough; The optical paths in N optical devices constitute the optical path, and N is an integer greater than or equal to 1.

8. A method for forming a packaging structure, characterized in that: The method comprises: Providing a first optical device; the first optical device is used to output a first optical signal transmitted along a first direction; forming an interposer, the interposer comprising a first surface and a second surface opposite to each other along a first direction and having an optical path transmitting along the first direction; The first optical device is bonded to the first surface of the interposer; wherein the first optical signal is subjected to at least one beam shaping through the optical path to generate a target optical signal; The first direction substantially intersects a surface of the first optical device.

9. The method for forming a packaging structure according to claim 8, characterized in that: The method further comprises: providing a secondary optic; The second optical device is bonded to the second surface of the intermediate layer; wherein the second optical device is used to receive and process the target optical signal.

10. The method for forming a packaging structure according to claim 8, wherein: Forming an interposer layer, including: Forming N sub-intermediation layers; each of the sub-intermediation layers comprises an optical device, and the optical device is used to perform the beam shaping on the first optical signal passing therethrough; N sub-intermediation layers are stacked in sequence along the first direction; the optical paths in the N optical devices constitute the optical path, where N is an integer greater than or equal to 1.

11. The method for forming a packaging structure according to claim 10, characterized in that: The optical device is an optical lens; Form a sub-interposer layer, including: Provide an initial sub-intermediation layer; The initial sub-interlayer is etched to form the sub-interlayer and at least one etched groove, wherein the sub-interlayer within the at least one etched groove projected along the first direction constitutes the optical lens; wherein the optical lens comprises a reflector, a convex lens or a concave lens.

12. The method for forming a packaging structure according to claim 11, characterized in that: The optical lens comprises at least one optical interface, and the optical interface is formed by the following steps: forming a first mask layer having a first pattern on the surface of the initial sub-interposer; the bottom of the first pattern is a curved surface or a flat surface; The initial sub-interlayer is etched through the first mask layer to remove the exposed portion of the initial sub-interlayer to form the etched groove; the curved surface or the flat surface at the bottom of the etched groove constitutes the optical interface.

Images