data communication device

Abstract

A communication device (22) comprises at least one semiconductor die (38) and an electronic integrated circuit (EIC) (14A) formed on a first side (34) of at least one die. The device also has at least one first array of micro-light-emitting diodes (micro-LEDs) (50) mounted on a second side (54) of at least one die opposite to the first side. The micro-LEDs are electrically connected to the EIC and configured to transmit outgoing light signals to each of the first optical fibers. The device also has at least one second array of photodiodes (60) mounted on the second side of at least one die. The photodiodes are electrically connected to the EIC and configured to receive incoming light signals from each of the second optical fibers.

Description

Technology Field

[0001] This application claims the benefit of U.S. provisional patent application No. 63 / 620,082 filed January 11, 2024, which is incorporated herein by reference.

[0002] The present disclosure generally relates to data communication, and in particular to data communication between integrated circuits. Background Technology

[0003] For facilities such as data centers to operate efficiently, extremely large amounts of data used by the center's Integrated Circuits (ICs) need to be transmitted rapidly between the ICs. Rapid data transmission within data centers is typically achieved through a combination of high-speed networking equipment, such as switches and routers, that support large bandwidths like 10 Gbps, 40 Gbps, 100 Gbps, and 400 Gbps or higher.

[0004] An embodiment of the present disclosure provides a communication device, and such communication device,

[0005] At least one semiconductor die and;

[0006] An Electronic Integrated Circuit (EIC) formed on a first side of at least one die;

[0007] At least one first array of micro-light-emitting diodes (micro-LEDs) mounted on a second surface of at least one die opposite to the first surface, wherein the micro-LEDs are electrically connected to an EIC and configured to transmit outbound optical signals to respective first optical fibers; and

[0008] It includes at least one second array of photodiodes mounted on a second surface of at least one die, wherein the photodiodes are electrically connected to an EIC and configured to receive inbound optical signals from each of the second optical fibers.

[0009] In the disclosed embodiments, the communication device also,

[0010] An optical element retained within a housing, wherein the optical element is configured to connect first optical fibers to at least one first array of micro-LEDs and to connect second optical fibers to at least one second array of photodiodes; and

[0011] It includes at least one channel formed within a second surface of at least one die, and

[0012] Here, a section of the housing is configured to fit snugly into at least one channel and is configured to align the optical element with at least one first array of micro-LEDs and at least one second array of photodiodes.

[0013] At least one channel can be formed at a pre-designed distance from at least one first array of micro-LEDs and at least one second array of photodiodes.

[0014] In an additionally disclosed embodiment, at least one first array of micro-LEDs comprises n first arrays, and at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays.

[0015] In an additionally disclosed embodiment, the communication device comprises conductive channels formed within at least one die, and an EIC, at least one first array of micro-LEDs, and at least one second array of photodiodes are connected to the conductive channels and configured to communicate with each other through the conductive channels.

[0016] The number of micro-LEDs defining at least one first array of micro-LEDs may be the same as the number of photodiodes defining at least one second array of photodiodes.

[0017] The EIC may be configured to convert outgoing data from the EIC from a parallel format to a serial format, and may be configured to provide the outgoing data in a serial format to micro-LEDs in at least one first array of micro-LEDs.

[0018] The EIC may be configured to receive incoming data in a serial format from photodiodes in at least one second array of photodiodes to the EIC, and may be configured to convert the incoming data from a serial format to a parallel format.

[0019] At least one semiconductor die may be a single die. Alternatively, at least one semiconductor die includes a stack of dies.

[0020] In an alternative embodiment, the communication device is,

[0021] An optical element retained within a housing, wherein the optical element is configured to connect first optical fibers to at least one first array of micro-LEDs and to connect second optical fibers to at least one second array of photodiodes; and

[0022] It includes a protrusion formed within a second surface of at least one die, and

[0023] Here, a portion of the housing includes a channel formed within the housing, and the channel is configured to fit snugly into a protrusion so as to align an optical element with at least one first array of micro-LEDs and at least one second array of photodiodes, and here, the protrusion and the channel are formed by etching.

[0024] According to an embodiment of the present disclosure, additionally, a method for aligning optical elements is provided, and such method,

[0025] Mounting a first optical element on the surface of a semiconductor die;

[0026] Forming at least one channel within the surface of the die in proximity to the first optical element;

[0027] Mounting a second optical element within the housing; and

[0028] Including configuring a portion of the housing to fit snugly into at least one channel, when the portion of the housing fits snugly into at least one channel, the first optical element is optically aligned with the second optical element.

[0029] In the disclosed embodiment, the first optical element comprises at least one first array of micro-light-emitting diodes (micro-LEDs) and at least one second array of photodiodes, and the second optical element comprises first optical fibers configured to be coupled with at least one first array of micro-LEDs and second optical fibers configured to be coupled with at least one second array of photodiodes.

[0030] The method may include forming at least one channel at a pre-designed distance from at least one first array of micro-LEDs and at least one second array of photodiodes.

[0031] In an additionally disclosed embodiment, at least one first array of micro-LEDs comprises n first arrays, and at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and wherein the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and wherein the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays.

[0032] According to an embodiment of the present disclosure, additionally, a communication device is provided, and the communication device is,

[0033] An interposer having multiple conductive channels;

[0034] An electronic integrated circuit (EIC) formed on at least one die and coupled to conductive channels;

[0035] At least one first array of micro-light-emitting diodes (micro-LEDs) mounted on an interposer, wherein the at least one first array of micro-LEDs is coupled to conductive channels and configured to receive data from an EIC through the conductive channels; and

[0036] It includes at least one second array of photodiodes mounted on an interposer, wherein at least one second array of photodiodes is coupled to conductive channels and configured to transmit data to an EIC through the conductive channels.

[0037] The interposer may have a first surface and a second surface opposite the first surface, wherein at least one die, at least one first array of micro-LEDs, and at least one second array of photodiodes are mounted on the first surface. There may be a plurality of surface-mounted terminals mounted on the second surface, wherein the surface-mounted terminals are connected to conductive channels and configured to transmit signals between the surface-mounted terminals and at least one first array of micro-LEDs, at least one second array of photodiodes, and the EIC.

[0038] In the disclosed embodiment, at least one first array of micro-LEDs is configured to transmit outgoing light signals to first optical fibers, and at least one second array of photodiodes is configured to receive incoming light signals from second optical fibers.

[0039] In an additionally disclosed embodiment, the communication device is,

[0040] An optical element retained within a housing, wherein the optical element is configured to connect first optical fibers to at least one first array of micro-LEDs and to connect second optical fibers to at least one second array of photodiodes; and

[0041] It includes at least one channel formed within the surface of the interposer, and

[0042] Here, a part of the housing is configured to fit snugly into at least one channel so as to align the optical element with at least one first array of micro-LEDs and at least one second array of photodiodes.

[0043] At least one channel can be formed at a pre-designed distance from at least one first array of micro-LEDs and at least one second array of photodiodes.

[0044] In an embodiment disclosed further, at least one first array of micro-LEDs comprises n first arrays, and at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and wherein the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and wherein the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays.

[0045] According to an embodiment of the present disclosure, additionally, a method for communication is provided, and such method,

[0046] Providing at least one semiconductor die;

[0047] Forming an electronic integrated circuit (EIC) on a first surface of at least one die;

[0048] Mounting at least one first array of micro-light-emitting diodes (micro-LEDs) on a second surface of at least one die opposite to the first surface, wherein the micro-LEDs are electrically connected to an EIC and configured to transmit leached optical signals to respective first optical fibers; and

[0049] It comprises forming at least one second array of photodiodes on a second surface of at least one die, wherein the photodiodes are electrically connected to an EIC and configured to receive incoming optical signals from each of the second optical fibers.

[0050] According to an embodiment of the present disclosure, a device for additionally aligning optical elements is provided, and such device,

[0051] Semiconductor die;

[0052] A first optical element mounted on the surface of a semiconductor die;

[0053] At least one channel formed within the surface of the die in proximity to the first optical element; and

[0054] It includes a second optical element mounted within a housing, and

[0055] Here, a part of the housing is configured to fit snugly into at least one channel, so that when a part of the housing fits snugly into at least one channel, the first optical element is optically aligned with the second optical element.

[0056] According to an embodiment of the present disclosure, additionally, a method for communicating is provided, and such method is,

[0057] Providing an interposer having multiple conductive channels;

[0058] Forming an electronic integrated circuit (EIC) on at least one die, and coupling the EIC to conductive channels;

[0059] Mounting at least one first array of micro-light-emitting diodes (micro-LEDs) on an interposer, wherein at least one first array of micro-LEDs is coupled to conductive channels and configured to receive data from an EIC through the conductive channels; and

[0060] The method comprises mounting at least one second array of photodiodes on an interposer, wherein at least one second array of photodiodes is coupled to conductive channels and configured to transmit data to an EIC through the conductive channels.

[0061] The present disclosure will be more fully understood from the following detailed description of embodiments of the present invention presented together with the drawings. Brief explanation of the drawing

[0062] FIG. 1 is a schematic example of elements of a data center facility according to an embodiment described in this specification. FIG. 2 is a schematic drawing of a side view and a top-down view of a communication device according to an embodiment described in this specification. This is a schematic example of the elements of a data center facility. FIG. 3 is a schematic drawing of a side view and a top view of an alternative communication device according to an embodiment described in this specification. FIG. 4 is a flowchart of steps for forming a communication device according to an embodiment described in this specification. FIG. 5 is a schematic diagram illustrating a method for coupling an optical fiber cable pair to a communication device according to an embodiment described in this specification. FIG. 6 is a flowchart of steps for combining two optical elements and aligning them according to an embodiment described in this specification. FIG. 7 is a schematic diagram of a side view of an additional alternative communication device according to an embodiment described in this specification. FIG. 8 is a flowchart of steps for producing a communication device using an interposer according to an embodiment described in this specification. FIG. 9 is a schematic block diagram illustrating data flow through a communication device according to an embodiment described in this specification. Specific details for implementing the invention

[0063] Overview

[0064] Within entities such as data center facilities and artificial intelligence systems, extremely large volumes of data need to be transmitted at high speeds, typically between the entities' Application Specific Integrated Circuits (ASICs). The required data transfer speed is typically approximately 100 Gbps or higher, but providing high-bandwidth channels capable of handling these high speeds is difficult. For example, these high-bandwidth channels combine Photonic Integrated Circuits (PICs) with ASICs using wire bonding and face-to-face assembly. However, both wire bonding and face-to-face assembly present problems: the former has limitations on interconnect density, while the latter requires cutting holes within the ASIC substrate or wire bonding to allow light to be coupled to the Photonic Integrated Circuit.

[0065] Embodiments of the present disclosure transmit a large amount of data to an ASIC using a communication device coupled to the ASIC, wherein the communication device integrates the data into a plurality of low bandwidth channels. Incoming data to the device is received by an array of photodiodes, and each photodiode of the array is coupled to each optical fiber within a bundle of optical fibers that optically carry the incoming data. Then, the incoming data from the photodiodes is transmitted to the ASIC.

[0066] Leakage data from the ASIC is carried to an array of micro-light-emitting diodes (micro-LEDs) within the communication device. Each micro-LED in the array is coupled to a respective optical fiber in another bundle of optical fibers that optically carry the leakage data.

[0067] Each fiber within an optical fiber bundle operates as a low-bandwidth channel, but the combined bundles provide the required high bandwidth for input and output.

[0068] In the embodiments described below, an ASIC is formed on a first active side of a die or a stack of dies. Micro-LED and photodiode arrays are mounted on a second side of the die or a stack of dies. The arrays operate as photonic integrated circuits, and the mounting of the arrays serves to separate the electronic integrated circuit from the photonic integrated circuit and does not require wire bonding. Additionally, as described herein, mounting the arrays on the die of the ASIC makes the entire system more compact, reduces the footprint of the entire system, and reduces overall power consumption.

[0069] In an alternative embodiment, a die containing an ASIC is mounted on the surface of a semiconductor interposer, and photodiode and micro-LED arrays are also mounted on the interposer. The ASIC and arrays are interconnected by conductive channels within the interposer. This configuration serves to separate the electronic integrated circuit from the photonic integrated circuit.

[0070] In the disclosed embodiment, the terminations of bundles of optical fibers coupled to arrays are fixed and held within an optical fiber housing connector. Alignment channels for the connector are etched into the surface of the die in proximity to the photodiode and micro-LED arrays. The connector is provided with a mechanical support structure that engages with the alignment channels so that each photodiode array is aligned to the terminations of its bundle of optical fibers, and each micro-LED array is aligned to the terminations of its bundle of optical fibers. Using alignment channels etched within the ASIC die enables precise, passive alignment of the optical fiber terminations to each of the photodiodes and micro-LEDs within the corresponding arrays, thereby avoiding the need for active optical alignment.

[0071] Detailed Description

[0072] In the following description, identical elements within the drawings are identified by identical numbers and distinguished by the addition of letters as necessary. Additionally, all directional references (e.g., up, down, upward, downward, left, right, upper, lower, above, below, vertical, and horizontal) are used solely for identification purposes to aid the reader's understanding of the present disclosure and do not create limitations, in particular, regarding the location, orientation, or use of the embodiments of the present disclosure.

[0073] Referring herein to FIG. 1, FIG. 1 is a schematic example of elements of a data center facility (10) according to an embodiment described herein. The facility (10) comprises a number of generally similar electronic integrated circuits (EICs) (14A, 14B, 14C, and 14D) (these are also referred to herein as ICs (14A, 14B, 14C, and 14D)). The ICs (14A, 14B, 14C, and 14D) are each mounted on a respective IC substrate (18A, 18B, 18C, 18D). The ICs (14A, 14B, ...) and IC substrates (18A, 18B, ...) are collectively referred to herein as ICs (14) and IC substrates (18). As necessary, similar conventions are used for other elements described herein. In some embodiments, the given IC (14) may include a graphic processing unit or a computer processing unit.

[0074] In order for ICs (14) to communicate with each other, one or more generally similar communication devices are coupled to each IC. For example, in the example, IC (14A) has four communication devices (22A, 22B, 22C, and 22D), IC (14B) has four communication devices (22E, 22F, 22G, and 22H), IC (14C) has four communication devices (22I, 22J, 22K, and 22L), and IC (14D) has four communication devices (22M, 22N, 22O, and 22P). The communication devices (22A, 22B, ...) are collectively referred to herein as communication devices (22). Each device (22) uses its respective IC and is assumed herein to include its respective IC.

[0075] Each device (22) receives outflow data from its IC and transmits this outflow data over a first optical fiber cable connected to the device. Additionally, each device (22) receives inflow data for its IC over a second optical fiber cable connected to the device and carries this inflow data to its IC. As described below, each optical fiber cable may have one or more optical fiber bundles, each bundle comprising a plurality of optical fibers. The first and second optical fiber cables operate together and are referred to herein as a cable pair.

[0076] Accordingly, each device (22) is connected to a cable pair (24), but for brevity, only one cable pair is illustrated in FIG. 1, namely, only a cable pair (24) connecting a communication device (22A) to a communication device (22E). The cable pair (24) has two cable endings, a first cable end (28A) and a second cable end (22B), and the connection between the devices (22A and 22E) is implemented by connecting the cable end (28A) to the device (22A) and connecting the cable end (28B) to the device (22E).

[0077] The cable pair (24) includes a first optical fiber cable (26A) and a second optical fiber cable (26B). The optical fiber cable (26A) carries outgoing data transmitted from device (22A) to device (22E), and at device (22E), this data is incoming data. The optical fiber cable (26B) carries outgoing data transmitted from device (22E) to device (22A), and at device (22A), this data is incoming data.

[0078] The structure and function of the communication device (22A), as well as its connection to the cable pair (24), are described in more detail below.

[0079] FIG. 2 is a schematic diagram of a side view and a top view of a communication device (22A) according to an embodiment described herein. As described above, the device (22A) includes an integrated circuit (IC) (14A). The IC (14A) is assumed herein to include, for example, an application-specific integrated circuit (ASIC), and is also referred to as the ASIC (14A). The ASIC (14A) is formed on a first active surface (34) of a semiconductor die (38).

[0080] In some embodiments, the die (38) is a single die, and in other embodiments, the die (38) is one of a stack of dies. For clarity and brevity in the present disclosure, the die (38) is assumed to be a single die having a second face (54) opposite to the first active face (34) (i.e., the face containing the ASIC (14A)). Those skilled in the art will be able to apply this description with only minor modifications as necessary, even if the die (38) is one of a stack of dies (wherein the stack has a second face corresponding to the second face (54)).

[0081] The device (22A) is mounted on a substrate (18A), which is assumed to be, for example, rectangular in this specification, and is coupled to the substrate by appropriate surface mounting terminals (46). For brevity, the device (22A) is shown on a set of orthogonal xyz axes. The axes are parallel to the edges of the substrate (18A) and have an origin at the center of the die (38), and the z-axis is normal to the substrate.

[0082] An array of micro-light-emitting diodes, (micro-LED) array (50), is fixedly mounted on a second side (54) of the die (38). The side (54) is also referred to herein as the back side (54). As described below, the micro-LED array (50) comprises a plurality of micro-LEDs (58), and the micro-LEDs are used to transmit data from the device (22A). A lens cap (66A) comprising a plurality of micro-lenses aligned with the micro-LEDs (58) covers the array (50). In the disclosed embodiment, all micro-LEDs (58) are configured to transmit at a single common wavelength (e.g., the color blue). Alternatively, the micro-LEDs (58) are configured to transmit at a plurality of other wavelengths corresponding, for example, the colors red, green, and blue.

[0083] An optical diode array (60) is also fixedly mounted on the rear surface (54) in close proximity to the array (50). The optical diode array (60) includes a plurality of optical diodes (64), and this array has the same number of optical diodes as the micro-LEDs (58) present in the array (50). A lens cap (66B) including a plurality of micro-lenses aligned with the optical diodes (64) covers the array (60). As described below, the optical diodes (64) are used by the device (22A) to receive data carried by optical signals.

[0084] The micro-LED array (50) and the photodiode array (60) may be formed from any suitable material known in the art of the present invention (e.g., silicon). Other suitable materials include aluminum gallium nitride for the micro-LED array (50) and gallium arsenide for the photodiode array (60), but are not limited to these.

[0085] In the disclosed embodiment, there are 400 micro-LEDs (58) in the micro-LED array (50) and 400 photodiodes in the photodiode array (60). Other embodiments may have any suitable number of micro-LEDs and photodiodes, more or less than 400, and the actual number may be determined by a person skilled in the art of the present invention according to engineering constraints on the size of the micro-LED array (50) and photodiode array (60) and the characteristics of the data being transmitted.

[0086] The array (50) and the array (60) may be fixedly mounted on the rear surface (54) by any suitable method. To implement the fixed mounting, the micro-LED array (50) has surface mounted pads (68), and these surface mounted pads (68) are connected to corresponding conductors (72) within the rear surface (54), and the photodiode array (60) has surface mounted pads (76), and these surface mounted pads (76) are connected to corresponding conductors (80) within the rear surface.

[0087] In the disclosed embodiment, the connection is implemented by forming conductors (72 and 80) within the rear surface (54) as conductive pillars, for example, of copper or gold. The pillars are surrounded by an insulating material (e.g., silicon dioxide). Then, the connection to the surface-mounted pads of the array can be implemented by any suitable bonding technique known in the art of the present invention. In the disclosed embodiment, this implementation is achieved by hybrid bonding the pads with connectors, and this hybrid bonding fuses the pads with the connectors.

[0088] In some embodiments, to enable the formation of conductive fillers, the thickness of the die (38) can be reduced by etching and / or grinding, typically to approximately 50 μm. The stability of this thinned die can be enhanced by attaching reinforcing structures to the back surface (54). In one embodiment, as illustrated, a conductive die attach film (84) is used to hold a reinforcing plate (88), and this plate can be formed from a semiconductor wafer such as silicon and / or glass and / or metal. To improve the thermal conductivity of the plate (88), a plurality of thermally conductive vias (96) or other suitable heat pipes can be incorporated within the plate to enhance the transfer of thermal energy from the ASIC (14A) when the ASIC (14A) is in operation. Thermally conductive vias (96) can also be incorporated within the rear surface (54) to further enhance thermal energy transfer.

[0089] When the surface mounting pads of the arrays are connected to each of these conductors within the rear surface (54), they can be used to supply power to the arrays and to carry data transmitted and received by the arrays. Conductive channels (98) and vias (100) are formed within the die (38) and configured to support power transfer to the arrays. The channels (98) and vias (100) also support data transfer from the photodiode array (60) to the ASIC (14A) and data transfer from the ASIC to the micro-LED array (50).

[0090] Alignment channels (92) are typically formed within the back surface (54) by etching, and the channels are formed at pre-designed distances from the array (50) and the array (60). The channels (92) are used to facilitate the coupling of optical fiber bundles to the array (50) and the array (60), as described below with reference to FIG. 5.

[0091] In an alternative embodiment not shown in the drawings, instead of channels being formed within the rear surface (54), protrusions are formed within the rear surface (54). The protrusions may be formed, for example, by etching a pair of parallel channels within the rear surface (54), and the protrusions include an unetched portion between the channels. As with the channels (92), the protrusions may also facilitate aligning and joining optical fiber bundles to the array (50) and array (60). The use of the protrusions for joining and alignment is described below.

[0092] FIG. 3 is a schematic diagram of a side view and a top view of an alternative communication device (122) according to an embodiment described herein. Except as described below, the operation of the device (122) is generally similar to the operation of the device (22A) (Figs. 1 and 2), and the elements indicated by the same reference numbers in both devices (22A and 122) are generally similar in configuration and operation.

[0093] In contrast to the device (22A) having a pair of micro-LED and photodiode arrays (i.e., a micro-LED array (50) and a photodiode array (60)), the device (122) includes two pairs of arrays (i.e., a first pair: a micro-LED array (50) and a photodiode array (60), and a second pair: a micro-LED array (150) and a photodiode array (160)). The micro-LED array (150) has a plurality of micro-LEDs (158) that are similar in structure and operation to the micro-LED array (50) and operate in a manner substantially similar to the micro-LEDs (58). The photodiode array (160) has a plurality of photodiodes (164) that are similar in structure and operation to the photodiode array (60) and operate in a manner similar to the photodiodes (64). As with the first pair of micro-LED and photodiode arrays, in the second pair of arrays described herein (i.e., array (158) and array (164)), the same number of micro-LEDs and photodiodes exist.

[0094] In some embodiments, the number of micro-LEDs in different micro-LED arrays is the same (and consequently, the number of photodiodes in different photodiode arrays is also the same). In some embodiments, the number of micro-LEDs in different micro-LED arrays is different (and consequently, the number of photodiodes in different photodiode arrays is also different).

[0095] The preceding disclosure describes communication devices having one pair and two pairs of micro-LED and photodiode arrays. Those skilled in the art may apply the present disclosure to communication devices having arrays of more than two pairs, with only minor modifications as necessary, and accordingly, the scope of the present disclosure includes communication devices having any suitable number of such pairs.

[0096] As described above with reference to FIG. 1, communication devices such as device (22A) use a pair of optical fiber cables to transmit and receive data. The following disclosure describes a process for connecting a pair of optical fiber cables to a communication device.

[0097] FIG. 4 is a flowchart (300) of steps for forming a communication device according to an embodiment described in the present specification.

[0098] For brevity, the flowchart description uses device (22A) as an example. Device (22A) has a single pair of micro-LED and photodiode arrays, and those skilled in the art of the present invention may apply this description to form communication devices having more than a single pair of micro-LED and photodiode arrays.

[0099] In the initial stage (304), an integrated circuit is formed on one side of the die, and the die is also prepared to accommodate micro-LED and photodiode arrays. In the example considered herein, an ASIC (14A) is formed on the active side (34) of the die (38). Additionally, conductors (72 and 80) are formed on the back side (54), and channels (98) and vias (100) are also formed within the die. The implementation of step (304) can be carried out by any method known in the art of the present invention, for example, by production in a manufacturing facility.

[0100] In the micro-LED array mounting step (308), the micro-LED array is mounted on the side of the die (38) opposite the active side. In the example herein, the array (50) is mounted on the conductors (72).

[0101] In the first coupling step (312), the micro-LEDs of the micro-LED array are configured to transmit data from the integrated circuit. Accordingly, the micro-LEDs (58) are configured to transmit data received from the integrated circuit using the channels (100) and vias (98).

[0102] In the photodiode array mounting step (316), the photodiode array is mounted on the side of the die (38) opposite the active side. In the example herein, the array (60) is mounted on the conductors (80).

[0103] In the second coupling step (320), the photodiodes of the photodiode array are configured to receive data for an integrated circuit. In the example herein, the photodiodes (64) are configured to receive data for an integrated circuit and to transmit data to the integrated circuit using channels (100) and vias (98).

[0104] FIG. 5 is a schematic diagram illustrating a method for coupling a pair of optical fiber cables (24) (exemplified in FIG. 1) to a communication device (22A) according to an embodiment described herein. As described above with reference to FIG. 1, the cable pair (24) comprises an optical fiber cable (26A) and an optical fiber cable (26B), and the cable end (28A) of the cable pair is coupled to the device (22A). Each optical fiber cable comprises at least one optical fiber bundle, the number of bundles is equal to the number of arrays connected to the cable, and each bundle is coupled to each array. Accordingly, in the case of a device (22A) having one micro-LED array (50) and one optical-diode array (60), the optical fiber cable (26A) has one optical fiber bundle (180) coupled to the micro-LED array (50), and the optical fiber cable (26B) has one optical fiber bundle (184) coupled to the optical-diode array (60).

[0105] (For a communication device (122) having two micro-LED arrays and two photodiode arrays, each cable of a pair of optical fiber cables connected to the device has two optical fiber bundles, and each bundle is connected to each array of the device. For devices having more than two micro-LED arrays and more than two photodiode arrays, it should be noted that the number of bundles in each cable scales accordingly.)

[0106] The ends of the fibers of the optical fiber bundle (180) are fixed at the bundle end (188), and the ends of the fibers of the optical fiber bundle (184) are fixed at the bundle end (192). The bundle ends (188 and 192) are fixed within the cable end (28A), and the cable end (28A) acts as a housing for the bundle ends and is also referred to herein as the housing (28A).

[0107] Housing supports (196) are fixedly attached to the housing (28A). The supports are configured to fit snugly within the channels (92) so that the ends of the fibers of the bundled end (188) are aligned with the micro-LEDs of the array (50) and are properly spaced from the micro-LEDs of the array (50), and the ends of the fibers of the bundled end (192) are aligned with the photodiodes of the array (60) and are properly spaced from the photodiodes of the array (60).

[0108] The dimensions of the channels (92) and housing supports (196) can be strictly controlled using suitable manufacturing techniques such as etching. Very high precision dimensional control facilitates the alignment described above and also enables manual alignment as described below.

[0109] In an embodiment, when the supports (196) fit snugly into the channels (92), the supports (196) are fixed to the channels so that the alignment described above exists during the operation of the device (22A). The fixation of the supports can be achieved by cementing the ends of the supports (196) to the channels (92) with any suitable adhesive material.

[0110] It should be noted that any misalignment of the arrays (50 and 60) and their respective bundle ends can reduce the operational efficiency of the device (22A) and even lead to a breakdown of the device's function.

[0111] In an alternative embodiment, the housing supports (196) are removablely attached to the housing (28A) and can be fixed to the channels (92) as described above. The removable attachment to the housing (28A) allows the cable pair (24) to be detached from the device and connected to the device (22A), so that the alignment described above exists when connected.

[0112] It should be noted that by using the channels (92), the alignment described above becomes passive alignment, and there is no requirement for active alignment to align the fibers of the optical fiber bundles to the arrays of the device (22A). Active alignment typically requires measuring the light intensity transmitted through one or more fibers of the bundle and adjusting the alignment between the bundle and the combined array to maximize the intensity. In passive alignment, such measurements or adjustments are not required.

[0113] The preceding disclosure describes a procedure for how fibers of a cable pair (24) are manually aligned to the elements of a pair of micro-LED and photodiode arrays, as in device (22A). Those skilled in the art of the present invention may apply this description with only minor modifications necessary to implement manual alignment for communication devices (e.g., device (122)) having more than one pair of micro-LED and photodiode arrays, and all such manual alignment procedures are assumed to be included within the scope of the present disclosure.

[0114] FIG. 6 is a flowchart (350) of steps for combining two optical elements and aligning them according to an embodiment described herein. The flowchart description uses the alignment system described earlier in FIG. 5 as an example, namely, an alignment system that aligns arrays (50 and 60) of the device (22A) to optical fiber bundles. The description also includes producing the device.

[0115] In the initial stage (354), the die is prepared to accommodate a first optical element, and at least one alignment channel is formed within the die in proximity to the location of the optical element. In the example herein, substantially as described above with reference to FIG. 2, the optical element comprises arrays (50 and 60), at least one channel comprises channels (92), and the arrays are mounted on the die.

[0116] In the housing step (358), the housing is prepared to accommodate a second optical element, and a portion of the housing is configured to fit snugly into at least one alignment channel so that when the portion fits snugly, the two optical elements are optically aligned. In the example herein, the portion includes housing supports (196), and the second optical element includes bundle ends (188 and 192).

[0117] In the completion stage (362), a portion is fitted into at least one alignment channel and then sealed into at least one alignment channel so that the alignment procedure and the production of the device (22A) are completed.

[0118] The prior description of alignment with reference to FIGS. 5 and 6 assumes that channels (92) are formed within the rear surface (54) and that housing supports (196) fit snugly within the channels (92). In an alternative embodiment, channels may be formed within the housing supports. As described above, rather than channels, protrusions may be formed within the rear surface (54), and the protrusions may be configured to fit snugly into the channels of the housing supports, so that when they fit snugly, the arrays are aligned to the bundle ends.

[0119] Those skilled in the art of the present invention may apply the description of FIGS. 5 and 6 by making only the necessary slight modifications to include alternative embodiments using protrusions within the rear surface (54).

[0120] FIG. 7 is a schematic side view of an additional alternative communication device (222) according to an embodiment described herein. Except as described below, the operation of the device (222) is generally similar to the operation of the device (22A) (Fig. 2), and the elements indicated by the same reference numbers in both devices (22A and 222) are generally similar in configuration and operation.

[0121] As in the case of device (22A), in device (222), an ASIC (14A) is formed on the active surface (34) of a semiconductor die (38). However, in contrast to device (22A), in device (222), a micro-LED array (50) and a photodiode array (60) are not mounted on the back surface (54) of the die (38), but are mounted on the first upper surface (226) of a semiconductor interposer (230) typically formed of silicon. Additionally, the die (38) is mounted on the interposer (230) so that the surface mounting terminals (46) of the ASIC (14A) are coupled to the upper surface (226). The second lower surface (234) of the interposer (230) is coupled to the substrate (18A) by surface mounting terminals (238), where the surface mounting terminals (238) are attached to the interposer and also to the substrate.

[0122] The interposer (230) includes conductive channels (242), wherein the conductive channels (242) connect the arrays (50 and 60) to the ASIC (14A) through terminals (46) and connect the arrays and the ASIC (14A) to the substrate (18A) through terminals (238). Substantially, as described above regarding the channels (98) and vias (100) of the device (22A), the channels (242) can be configured to supply power to the arrays (50 and 60) and the ASIC (14A), as well as to transmit data signals between the arrays, the ASIC, and the substrate.

[0123] In some embodiments, alignment channels (250) are formed within the upper surface (226) at pre-designed distances from the arrays (50 and 60), typically by etching or other suitable high-precision channel manufacturing technique. The channels (250) are substantially similar to the alignment channels (92) and perform the same function as the alignment channels (92), namely, facilitating manual alignment to align the ends of the fiber bundles of the cable pairs to the arrays (50 and 60), as described above with reference to FIGS. 5 and 6.

[0124] The description of the device (222) assumes that the device has one micro-LED array (50) and one photodiode array (60). Those skilled in the art of the present invention may apply this description with only minor modifications necessary to communication devices (e.g., comparable to the device (122)) having more than one micro-LED array and more than one photodiode array, and accordingly, the scope of the present disclosure includes communication devices using an interposer having more than one micro-LED array and more than one photodiode array.

[0125] FIG. 8 is a flowchart (400) of steps for producing a communication device using an interposer according to an embodiment described herein. For brevity, the description of the steps in the flowchart is, for example, using elements of the device (222), and those skilled in the art may apply this description to other communication devices using an interposer.

[0126] In the initial stage (404), the semiconductor interposer is implemented to have a plurality of conductive channels. In the example of this specification, the interposer is an interposer (230) having conductive channels (242).

[0127] In the integrated circuit step (408), the integrated circuit is formed on the die (die (38) in this specification) and coupled to the conductive channels of the interposer.

[0128] In the micro-LED step (412), an array of micro-LEDs (array (50) in this specification) is mounted on the interposer, substantially as described above with respect to the interposer (230). The micro-LEDs of the array are coupled to the channels of the interposer and configured to receive data from an integrated circuit.

[0129] In the photodiode step (416), an array of photodiodes (array (60) in this specification) is mounted on the interposer, substantially as described above with respect to the interposer (230). The photodiodes of the array are coupled to the channels of the interposer and configured to transmit data to an integrated circuit.

[0130] FIG. 9 is a schematic block diagram illustrating a data flow through the communication devices described herein according to an embodiment described herein. This diagram is illustrated using elements of the device (22A) and can be applied to other communication devices described herein with only minor modifications as necessary.

[0131] As exemplified by a pair of two-way arrows, data is transferred between the ASIC (14A) and the substrate (18A) in a substantially parallel format. Data can also be generated within the ASIC (14A) in a parallel format.

[0132] Data flowing out from the ASIC (14A) is transmitted from the ASIC to the micro-LED array (50) in a substantially serial format, as exemplified by the unidirectional arrow, and from the micro-LED array (50) to a plurality of fibers within the optical fiber bundle (180). Data flowing into the ASIC (14A) is received from a plurality of fibers within the optical fiber bundle (184) in a substantially serial format by the photodiode array (60). Data is transmitted from the photodiode array to the ASIC (14A) in a serial format.

[0133] It should be noted that the communication devices described herein may incorporate redundancy in the operation of the devices. Typically, when a micro-LED array in a first communication device is connected to an optical diode array in a second communication device by an optical fiber bundle as described above, not all of the fibers in the bundle are used because the corresponding micro-LEDs and optical diodes are not activated. If one of the operating fibers fails due to a breakage within the fiber or due to a failure of a micro-LED or optical diode, one of the unused fibers may be activated to replace the failed fiber.

[0134] It should be noted that the embodiments described above are cited by way of example and that the present disclosure is not limited to what has been specifically shown and described above. Rather, the scope of the present disclosure includes both combinations and partial combinations of the various features described above, as well as modifications and changes thereto that are not disclosed in the prior art and that would occur to those skilled in the art when reading the foregoing description.

Claims

Claim 1 A communication device comprising: at least one semiconductor die; an Electronic Integrated Circuit (EIC) formed on a first side of the at least one die; at least one first array of micro-Light Emitting Diodes (micro-LEDs) mounted on a second side of the at least one die opposite to the first side, wherein the micro-LEDs are electrically connected to the EIC and configured to transmit outbound optical signals to respective first optical fibers; and at least one second array of photodiodes mounted on the second side of the at least one die, wherein the photodiodes are electrically connected to the EIC and configured to receive inbound optical signals from respective second optical fibers. Claim 2 In claim 1, the communication device also comprises an optical element held within a housing, wherein the optical element is The first optical fibers are configured to be coupled to at least one first array of micro-LEDs, and A communication device characterized by being configured to combine the second optical fibers to the at least one second array of photodiodes; and including at least one channel formed within the second surface of the at least one die, wherein a section of the housing is configured to fit snugly into the at least one channel so as to align the optical element with the at least one first array of micro-LEDs and the at least one second array of photodiodes. Claim 3 A communication device according to claim 2, wherein the at least one channel is formed at a predetermined distance from the at least one first array of micro-LEDs and the at least one second array of photodiodes. Claim 4 A communication device according to claim 2, wherein the at least one first array of micro-LEDs comprises n first arrays, and the at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays. Claim 5 In claim 1, the communication device also includes conductive channels formed within the at least one die, and the EIC, the at least one first array of micro-LEDs, and the at least one second array of photodiodes are, Connected to the above conductive channels and A communication device characterized by being configured to communicate with each other through the above-mentioned conductive channels. Claim 6 A communication device according to claim 1, characterized in that the number of micro-LEDs defining the at least one first array of micro-LEDs is the same as the number of photodiodes defining the at least one second array of photodiodes. Claim 7 In paragraph 1, the above EIC is, It is configured to convert outgoing data from the above EIC from a parallel format to a serial format, and A communication device characterized by being configured to provide the above-mentioned leaked data in the above-mentioned serial format to micro-LEDs within at least one first array of micro-LEDs. Claim 8 In paragraph 1, the above EIC is, It is configured to receive incoming data in a serial format to the EIC from photodiodes in the at least one second array of photodiodes, and A communication device characterized by being configured to convert the above-mentioned input data from the above-mentioned serial format to the above-mentioned parallel format. Claim 9 A communication device according to claim 1, wherein the at least one semiconductor die comprises a single die. Claim 10 A communication device according to claim 1, wherein the at least one semiconductor die comprises a stack of dies. Claim 11 In claim 1, the communication device also comprises an optical element held within a housing, wherein the optical element is The first optical fibers are configured to be coupled to at least one first array of micro-LEDs, and A communication device characterized by being configured to combine the second optical fibers to the at least one second array of photodiodes; and including a protrusion formed within the second surface of the at least one die, wherein a portion of the housing includes a channel formed within the housing, and the channel is configured to fit snugly into the protrusion to align the optical element with the at least one first array of micro-LEDs and the at least one second array of photodiodes, and wherein the protrusion and the channel are formed by etching. Claim 12 A method for aligning optical elements, wherein the method comprises: mounting a first optical element on the surface of a semiconductor die; forming at least one channel within the surface of the die in proximity to the first optical element; mounting a second optical element within a housing; and configuring a portion of the housing to fit snugly into the at least one channel, wherein when the portion of the housing fits snugly into the at least one channel, the first optical element is optically aligned with the second optical element. Claim 13 In paragraph 12, the first optical element is, At least one first array of micro-light-emitting diodes (micro-LEDs), and It includes at least one second array of photodiodes, and the second optical element is First optical fibers configured to be coupled with at least one first array of micro-LEDs, and A method for aligning optical elements characterized by including second optical fibers configured to be coupled with at least one second array of photodiodes. Claim 14 A method for aligning optical elements according to claim 13, wherein the method comprises forming the at least one channel at a predetermined distance from the at least one first array of micro-LEDs and the at least one second array of photodiodes. Claim 15 A method for aligning optical elements according to claim 13, wherein the at least one first array of micro-LEDs comprises n first arrays, and the at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays. Claim 16 A communication device comprising: an interposer including a plurality of conductive channels; an electronic integrated circuit (EIC) formed on at least one die and coupled to the conductive channels; at least one first array of micro-light-emitting diodes (micro-LEDs) mounted on the interposer, wherein the at least one first array of micro-LEDs is coupled to the conductive channels and configured to receive data from the EIC through the conductive channels; and at least one second array of photodiodes mounted on the interposer, wherein the at least one second array of photodiodes is coupled to the conductive channels and configured to transmit data to the EIC through the conductive channels. Claim 17 A communication device according to claim 16, wherein the interposer comprises a first surface and a second surface opposite to the first surface, and wherein the at least one die and the at least one first array of micro-LEDs and the at least one second array of photo-diodes are mounted on the first surface. Claim 18 In paragraph 17, the communication device comprises a plurality of surface-mounted terminals mounted on the second surface, and the surface-mounted terminals are Connected to the above conductive channels, and A communication device characterized by being configured to transmit signals between the surface-mounted terminals, the at least one first array of micro-LEDs, the at least one second array of photodiodes, and the EIC. Claim 19 A communication device according to claim 16, wherein at least one first array of micro-LEDs is configured to transmit outgoing optical signals to first optical fibers, and at least one second array of photodiodes is configured to receive incoming optical signals from second optical fibers. Claim 20 In paragraph 19, the communication device also comprises an optical element held within a housing, wherein the optical element is The first optical fibers are configured to be coupled to at least one first array of micro-LEDs, and A communication device characterized by being configured to combine the second optical fibers to the at least one second array of photodiodes; and including at least one channel formed within the plane of the interposer, wherein a portion of the housing is configured to fit snugly into the at least one channel so as to align the optical element with the at least one first array of micro-LEDs and the at least one second array of photodiodes. Claim 21 A communication device according to claim 20, wherein the at least one channel is formed at a predetermined distance from the at least one first array of micro-LEDs and the at least one second array of photodiodes. Claim 22 A communication device according to claim 20, wherein the at least one first array of micro-LEDs comprises n first arrays, and the at least one second array of photodiodes comprises n second arrays, wherein n is a positive integer, and the first optical fibers comprise n first optical fiber bundles aligned with the n first arrays, and the second optical fibers comprise n second optical fiber bundles aligned with the n second arrays.

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