Interposer assemblies and arrangements for coupling at least one optical fiber to at least one optoelectronic device

[0028] Figure 1A with 1B Is shown in an unfit state ( Figure 1A ) And cooperation status ( Figure 1B ) An illustrative arrangement 10 for coupling at least one optical fiber to at least one optoelectronic device. The arrangement 10 is disclosed in detail to convey the operation and concept of the inserter assembly 1. The interposer assembly 1 includes an interposer 100 that includes at least one optical waveguide 110 having a first end 111 and a second end 112 optically coupled to at least one optical fiber 200. The arrangement also includes a coupling device 300 for optically coupling the at least one optical fiber 200 to the interposer 100 and aligning the at least one optical fiber 200 to the at least one optical waveguide 110 so as to be between the at least one optical fiber 200 and the at least one optical waveguide 110 Transmission light.

[0029] The coupling device 300 includes a first part 310 provided at the end 201 of at least one optical fiber 200 and a second part 320 provided at the edge of the inserter 100. The first and second parts 310, 320 of the coupling device 300 are configured such that when the first part 310 of the coupling element is mechanically coupled to the second part 320 of the coupling device 300, at least one optical fiber 200 can be optically coupled to the interposer 100 edge.

[0030] The design of the coupling device 300 can vary. According to possible implementations of arrangement 1, the coupling device 300 may be configured as an MTP/MPO or other interface. The first part of the coupling device may be configured as one of an MT ferrule-based connector or a lens-based connector. The second part 320 of the coupling device 300 may be configured as a socket. By way of example and not limitation, the MT ferrule-based connector may be a pin physical contact connector, and the lens-based connector may be an expanded beam connector.

[0031] The second end 112 of the at least one optical waveguide 110 is configured to couple light into/from the at least one optical waveguide 110. The arrangement also includes a substrate 400 including at least one optoelectronic device 410, such as a photonic integrated circuit, at least one light receiving/emitting element 420, such as a grating coupler, VCSEL or photodiode, and at least one optical channel 430. The at least one optical channel 430 may have a first end 431 that is connected to the at least one light receiving/emitting element 420 to couple light into/from the at least one optical channel 430 At least one optoelectronic device 410 is coupled to the second end 432 and connected to the second end 432.

[0032] The optical fiber 200 is terminated with the first part 310 of the coupling device inserted into the socket 320. The connector 310 and the socket 320 provide alignment such that the at least one optical fiber 200 is aligned with the at least one optical waveguide 110 and allows low loss coupling. In addition, the connector 310 provides repeated coupling of at least one optical fiber 200 and the interposer 100.

[0033] figure 2 The arrangement of the interposer 100 and the substrate 400 is shown. The substrate 400 includes at least one optoelectronic device 410, at least one light receiving/emitting element 420, and at least one optical channel 430. The interposer 100 and the substrate 400 are arranged such that the light coupled from the at least one optical waveguide 110 at the second end 112 of the at least one optical waveguide 110 is coupled into the at least one light receiving/emitting element 420 and/or from the at least one The light coupled by the light receiving/transmitting element 420 is coupled into the at least one optical waveguide 110 at the second end 112 of the at least one optical waveguide 110. The substrate/chip 400 may be arranged under the lower surface of the interposer 100. The substrate/chip 400 may be attached to the lower surface of the interposer 100, for example.

[0034] according to figure 2 In the illustrated embodiment of the arrangement, the second end 112 of the at least one optical waveguide 110 is cut at an angle to provide total internal reflection (TIR) ​​at the end face 113 of the at least one optical waveguide 110 so that the at least one optical waveguide 110 The light transmitted in the interposer is reflected toward at least one receiving/emitting element 420 of the substrate via the optical path 101 in the material of the interposer. For this purpose, such as Figure 1A to 2 The inserter is shown cutting/cutting to provide a TIR area/cavity 102 in the surface of the inserter. One side of the cavity is inclined at an angle to provide total internal reflection at the end face 113 of at least one optical waveguide 110.

[0035] The light coupled to the at least one light receiving/emitting element 420, such as a grating coupler or a photodiode, may be transmitted to at least one optoelectronic device 410, such as a photonic integrated circuit, via at least one optical channel 430. The direction of light can be bidirectional, which means that at least one light receiving/emitting element 420, such as a grating coupler or VCSEL, can also be used to transmit optical signals instead of receiving optical signals. In this case, light will couple from at least one receiving/transmitting element 420 to the interposer 100, where it is guided into the waveguide 110, for example by total internal reflection. Then, the light is coupled from the at least one optical waveguide 110 into the at least one optical fiber 200 installed at the edge of the interposer at the connector interface 300.

[0036] In the case of using a grating coupler as a light receiving/transmitting structure, in order to couple in a given direction, the light beam is not emitted perpendicular to the at least one receiving/transmitting element 420, but at a predetermined angle, for example, relative to the The longitudinal direction of the optical waveguide 110 emits at an angle of about 8°. The precise grating design of the at least one light receiving/transmitting element 420 will depend on many parameters, including wavelength, the mode shape of the at least one optical waveguide 110, the distance between the waveguide 110 and the grating structure of the at least one receiving/transmitting element 420, and so on. The inclined end face 113 of the at least one optical waveguide 110 can be made by an etching process or laser processing, which is very accurate and can be adapted to different angles to provide total internal reflection (TIR) ​​when necessary.

[0037] According to another embodiment, the end surface 113 may be coated with a reflective coating to reflect the light coupled from the at least one optical waveguide 110 toward the grating structure of the at least one light receiving/emitting element 420 or to receive/transmit light from at least one light. The light coupled by the grating structure of the element 420 is reflected into the core of at least one optical waveguide 110.

[0038] Depending on the relative size and distance between at least one optical waveguide 110, interposer 100, and any substrate including at least one optoelectronic device (such as a photonic integrated circuit), when coupling light from at least one optical waveguide to at least one In the case of optoelectronic devices, the light beam can be expanded in the optical path 101 to be larger than the size of the grating structure of the light receiving/emitting element 420, or when the light from the grating structure of at least one receiving/emitting element 420 is coupled to the interposer 100, the light beam It can be expanded to a size larger than the diameter of at least one optical waveguide 110. In order to provide high coupling efficiency, an additional optical lens 130 may be provided in the material of the interposer arranged in the optical path 101 of the light to focus the light.

[0039] according to image 3 An embodiment of the arrangement shown, the arrangement comprising an optical lens 130 arranged within the material of the interposer 100 in the optical path 101 of light. The second end 112 of the at least one optical waveguide 110 is configured such that light coupled from the at least one optical fiber 200 into the at least one optical waveguide is in the at least one optical waveguide at the second end 112 of the at least one optical waveguide. The end surface 113 of the 110 is reflected so as to be transmitted toward the substrate 400 through the optical path 101 and the optical lens 130.

[0040] The optical lens 130 is configured to focus light to the receiving/emitting element 420 of the substrate 400. In order to be able to couple light from at least one optoelectronic device (such as a photonic integrated circuit) into the at least one optical waveguide 110, the optical lens 130 may be configured to direct the light incident from the at least one receiving/emitting element 420 to the optical lens 130 toward at least An optical waveguide 110 is focused. Optical lenses can be manufactured by ion exchange or laser marking processes.

[0041] In order to achieve high coupling efficiency between at least one optical fiber, at least one optical waveguide, and light receiving/transmitting element, it is not only necessary to adjust the SM mode fields relative to each other, but also to control the polarization, because light receiving/transmitting elements such as grating couplers are Very polarization sensitive.

[0042] According to an embodiment of this arrangement, at least one light receiving/emitting element 420 may be configured to receive/emit light having the first polarization P1 with a lower loss than light having the second polarization P2. According to the embodiment of the at least one optical waveguide 110 of the interposer 100, the at least one optical waveguide 110 may be configured to select the first polarization P1 from the polarization of the light coupled into the at least one optical waveguide 110 at the first end 111 of the waveguide. , So that the light coupled out at the second end 112 of the at least one optical waveguide 110 has the first polarization P1 and/or the second polarization is selected from the polarization of the light coupled into the at least one optical waveguide 110 at the second end 112 P2 makes the light coupled out at the first end 111 of the at least one optical waveguide 110 have a second polarization P2 different from the first polarization P1.

[0043] according to Figure 4 In the illustrated embodiment, the cross section of the at least one optical waveguide 110 changes along the longitudinal direction of the at least one optical waveguide, for example, adiabatically, so that the polarization of the light coupled into the at least one optical waveguide 110 at the first end 111 is selected. The first polarization P1 makes the light coupled at the second end 112 of the at least one optical waveguide 110 have the first polarization P1, and/or select the polarization of the light coupled into the at least one optical waveguide 110 at the second end 112 The second polarization P2 makes the light coupled out at the first end 111 of the at least one optical waveguide have the second polarization P2. One axis of the cross section of the optical waveguide is elongated, and the other axis of the cross section arranged in a plane perpendicular to the cross section of the elongate axis is shortened or kept constant.

[0044] By changing the cross section of the at least one optical waveguide 110, that is, the core 116 of the at least one optical waveguide along its longitudinal direction in the material of the interposer, for example adiabatic adjustment, the mode of light transmitted in the core of the optical waveguide is selected. Polarization. Figure 4 The shape of the core 116 of the at least one optical waveguide 110 is schematically shown slowly changing from a square or circular cross-section to a rectangular or elliptical cross-section supporting only one polarization, which needs to be based on receiving/transmitting elements, such as grating coupling. The grating structure of the device is required to adjust the specific polarization. In the proposed design, the reflection of light is polarization-dependent, so the angle at which the total internal reflection (TIR) ​​occurs must be adjusted to take into account the polarization of the light.

[0045] The principle of selecting the polarization of light by changes in the cross-section of the core 116 of the optical waveguide 110 (e.g., adiabatic changes) can be supported by ensuring that additional features that exclude other polarizations. For this purpose, air-filled circular grooves, channels or holes can be arranged in the material of the interposer along the extension of the core of at least one optical waveguide, such as Figure 5A with 5B Shown.

[0046] according to Figure 5A with 5B In the illustrated embodiment of the arrangement, the inserter 100 may include an air-filled channel 120 arranged in the at least one optical waveguide 110 along the longitudinal direction of the at least one optical waveguide, adjacent to the core portion 116 of the at least one optical waveguide. In the cladding 115. The choice of polarization can be supported by adding air-filled holes/channels 120 near the core 116 along the longitudinal direction of the optical waveguide. The two air holes/channels 120 may be arranged in the cladding 115 of the optical waveguide on both sides of the core 116 of the optical waveguide symmetrically with respect to the extension axis of the core of the optical waveguide.

[0047] according to Figure 5A In the illustrated embodiment, the circular cross-section of the optical core 116 of at least one optical waveguide becomes elliptical. The first and second air holes/channels 120 are symmetrically arranged on both sides of the extension axis of the cross section of the core 116 of the optical waveguide. according to Figure 5B In the illustrated embodiment, the square cross section of the core 116 of the optical waveguide changes into a rectangular shape along the longitudinal direction of the optical waveguide from the first end 111 to the second end 112 of the optical waveguide.

[0048] Image 6 An example of the layout of the interposer 100 is shown, which is coupled to a plurality of substrates/chips 400 a, 400 b, and 400 c that may be arranged under the interposer 100. The interposer 100 includes a coupling device 300 arranged at the edge of the interposer 100. The coupling device 300 may be configured as a socket 320. The optical fiber may be connected to the waveguide 100 in the material of the interposer 100 through the coupling device 300. The optical signal coupled from the optical waveguide 100, such as an optical fiber in the waveguide array, can be transmitted to the receiving/transmitting element 420 of the substrate 400 by total internal reflection at the corresponding end face 113 of the optical waveguide at the region 102 of the interposer.

[0049] The light coupled out of the optical waveguide 110 and received by the corresponding grating coupler 420 of the substrate 400 may be transferred to the photonic integrated circuit of the substrate 400a, 400b, 400c. Other optoelectronic devices 500a, 500b, such as VECSELs or photodiodes, may also be coupled to the interposer 100. Light may be coupled from the VECSEL 500a to the region 102 via the optical waveguide 110, where the light is reflected toward the grating coupler of the substrate/chip 400c by total internal reflection. In addition, the optical signal can be transmitted from the optoelectronic device of the substrate/chip 400b to the grating coupler of the substrate 400b, and be coupled into the optical waveguide of the interposer 100 through total internal reflection. The light is transmitted to the photodiode 500b through the optical waveguide 110.

[0050] Image 6 The embodiment of the layout of the interposer shown in allows coupling of signals from the waveguide array to at least one grating structure of the receiving/transmitting element such as the grating coupler array by total internal reflection at the area 102 of the interposer 100. In addition, a connection between a single waveguide and a single grating coupler or optoelectronic element is also possible.

[0051] When designing the optical channel 430 of the interposer 100 and the substrate 400 for two polarization directions, optical waveguides and optical channels can be applied so that at least the polarization sensitivity of the grating structure of the receiving/transmitting element, such as the grating coupler, is not affected. Loss of power. Figure 7 An embodiment of the arrangement of the interposer 100 and the substrate 400 is shown, wherein the substrate 400 includes the first receiving/transmitting element of at least one receiving/transmitting element 421, which is configured to have a lower polarization than the one having the second polarization P2 Light lower loss to receive/emit light with the first polarization P1. The substrate 400 may include a second receiving/transmitting element among at least one receiving/transmitting element 422, which is configured to receive/transmit light with the second polarization P2 at a lower loss than light with the first polarization P1 .

[0052] The at least one optical waveguide 100 may include a first portion 110a, a second portion 110b, and a third portion 110c. The at least one optical waveguide 100 may include a third end 113 and a separation node 114 where the first part 110a is separated into second and third parts 110b, 110c. The first portion 110 a of the at least one optical waveguide 110 extends from the first end 111 of the at least one optical waveguide to the separation node 114 within the interposer 100. The second portion 110 b of the at least one optical waveguide 110 extends from the separation node 114 to the second end 112 of the at least one optical waveguide 110 within the material of the interposer 100. The third portion 110c of the at least one optical waveguide 110 extends from the separation node 114 to the third end 113 of the at least one optical waveguide 110 within the interposer 100. The second end 112 of the at least one optical waveguide 110 is configured to couple light into/out of the second portion 110b of the at least one optical waveguide. The third end 113 of the at least one optical waveguide is configured to couple light into/out of the third portion 110c of the at least one optical waveguide.

[0053] The interposer 100 and the substrate 400 are arranged so that the light coupled from the second portion 110b of the at least one optical waveguide at the second end 112 is coupled into the first light receiving/emitting element 421, and/or from the first light The light coupled by the receiving/transmitting element 421 is coupled into the second part 110b of the at least one optical waveguide at the second end 112.

[0054] The interposer 100 and the substrate 400 are also arranged so that the light coupled from the third portion 110c of the at least one optical waveguide at the third end 113 is coupled into the second light receiving/emitting element 422, and/or from the second light receiving/emitting element 422. The light coupled by the light receiving/transmitting element 422 is coupled into the third portion 110c of the at least one optical waveguide 110 at the third end 113.

[0055] according to Figure 7 In the coupling structure shown in, the optical fiber is coupled to the interposer 100 at the socket 320 and optically coupled into the waveguide 110. The first part 110a of the waveguide 100 is divided into two separate parts 110b and 110c of the waveguide at the separation node 114. The cross-section of the second portion 110b of the optical waveguide 110 may be changed between the separation node 114 and the second end 112 of the optical waveguide 110, for example, adiabatically, so that the option is coupled to the second portion 110b of the optical waveguide at the separation node 114 The first polarization P1 of the polarization of the light so that the light coupled out at the second end 112 of the optical waveguide has the first polarity P1. Light is transmitted from the second portion 110b of the optical waveguide to the first receiving/transmitting element 421.

[0056] The second portion 110 b of the optical waveguide 110 is coupled to the first receiving/transmitting element 421. The cross-section of the third portion 110c of the optical waveguide 110 may be changed between the separation node 114 and the third end 113 of the optical waveguide 110, for example, adiabatically, so that the option is coupled to the third portion 110c of the optical waveguide at the separation node 114 The second polarization P2 of the polarization of the light so that the light coupled out at the third end 113 of the optical waveguide has the second polarity P2. The light is transmitted from the third part 110c of the optical waveguide to the second receiving/transmitting element 422.

[0057] according to Figure 7 In the embodiment shown in, at least one optical channel 430 includes a first path 430a, a second path 430b, and a third path 430c. The at least one optical channel 430 further includes a third end 433 and a merging node 434, where the first and third paths 430a, 430c of the optical channel merge into a second path 430b. The first path 430 a of the at least one optical channel extends from the first end 431 of the at least one optical channel to the merging node 434. The first end 431 of the at least one optical channel is connected to the first receiving/transmitting element 421. The second path 430b of the at least one optical channel extends from the merging node 434 to the second end 432 of the at least one optical channel. The third path 430c of the at least one optical channel extends from the third end 433 of the at least one optical channel to the merging node 434. The third end 433 of the at least one optical channel is connected to the second receiving/transmitting element 422.

[0058] The first and third parts 430a, 430c of the optical channel meet at the joining/merging node 434, from which the single second part 430b of the optical channel extends to the functional structure/optoelectronic device 410. The trajectory between the optoelectronic device 410 and the first portion 110a of the optical waveguide 110 can also be followed in the opposite direction.

[0059] In order to maintain signal integrity, it is necessary to ensure that the optical path length of each signal has substantially the same length, so that the length between the second portion 110b of the optical waveguide, the end surface of the second portion 110b of the optical waveguide and the first light receiving/transmitting element 421 The length of the optical path 101 and the first part 430a of the optical channel 430 is equal to the optical path 101 between the third part 110c of the optical waveguide, the end face of the third part 110c of the optical waveguide and the receiving/transmitting element 422, and the optical channel The length of the optical path of the third part 430c of the 430.

[0060] As described above, the second and third parts 110b, 110c of the optical waveguide 110 may be configured to select the polarization of the light so that the light coupled out at the end surface of the second part 110b of the optical waveguide 110 has the first polarization P1, and The light coupled from the third portion 110c of the optical waveguide 110 has the second polarization P2. The cross-sections of the respective cores of the second and third portions 110b, 110c of the optical waveguide may be between the separation node 114 and the end of the second portion 110b of the optical waveguide and between the separation node 114 and the end of the third portion 110c of the optical waveguide. Change in different ways.

[0061] In order to receive/emit light having different polarities with low loss, the first and second light receiving/emitting elements 421, 422 are arranged on the surface of the substrate 400 and turned at a certain angle relative to each other. For example, the steering of the signal may be an angle of about 90°.

[0062] Figure 8A with 8B It shows how to ensure low-loss coupling of different polarizations from the optical waveguide 110 to the light receiving/emitting element 420 by adjusting the orientation of the grating structure of the light receiving/emitting element and the end face 113 of the optical waveguide 110, that is, the inclination of the TIR mirror. according to Figure 8A , The light is reflected toward the light receiving/emitting element 420 through the cut end face 113 of the optical waveguide. The cut end face has y=41° in the y direction perpendicular to the longitudinal direction of the optical waveguide and in the x direction perpendicular to the y direction. The inclination of x=0° makes the direction of the light form an angle of 8° with the normal, so that the light is optimally coupled to the substrate/chip 400. Due to the arrangement of the grating structure of the light receiving/emitting element 420, only the transverse electrical (TE) mode is coupled into the optical channel 430, and the transverse magnetic (TM) mode is not coupled to the optical channel 430.

[0063] according to Figure 8B In the illustrated embodiment, the grating structure of the light receiving/emitting element 420 is Figure 8A The grating structure of the light receiving/emitting element 420 is rotated by approximately 90° and the direction of the TIR mirror of the end face 113 of the optical waveguide is changed to couple only the TM mode to the light receiving/emitting element 420. The end face 113 of the optical waveguide is cut at y=45° in the y direction and x=4° in the x direction. This means that the TIR mirror is 45° in the direction perpendicular to the longitudinal direction of the waveguide, and forms an angle of about 4° in the direction perpendicular to the y direction.

[0064] Pass as Figure 8A As shown, the end surface 113 of the second part 110b of the optical waveguide provides a TIR mirror, and passes as Figure 8A The grating structure of the first light receiving/emitting element 421 is arranged as shown, and the Figure 8B As shown, providing the orientation of the end face 113 of the third part 110c of the optical waveguide and the grating structure of the second light receiving/emitting element 422, two polarizations, namely the TE mode and the TM mode, can be coupled to the optoelectronic device 410.

[0065] According to a method of manufacturing an arrangement for coupling at least one optical fiber 200 to at least one optoelectronic device 410, an interposer 100 may be provided that includes at least one optical waveguide 110 that matches the mode field of the at least one optical fiber 200. In order to couple the optoelectronic device 410 (e.g., photonic integrated circuit) to at least one optical fiber 200 through the receiving/transmitting element 420 (e.g., grating coupler), at least one optical waveguide 110 needs to be single-mode.

[0066] Manufacturing a single-mode waveguide in the material of the interposer 100 can be achieved by an ion exchange process, in which the surface of the interposer is bombarded by ions that locally change the material of the interposer, such as the refractive index of the glass of the interposer 100, followed by a diffusion process. The optical waveguide 110 is buried in the interposer 100 through this diffusion process. The second method of manufacturing at least one optical waveguide 110 is to directly write at least one optical waveguide in the material (for example, glass) of the interposer 100 using a femtosecond laser. By carefully selecting process parameters, such as the width of the trace in the mask used for ion bombardment and the subsequent diffusion time or the size of the laser-inscribed waveguide, the waveguide can be made single-mode at the desired wavelength so that it can be coupled To SM fiber and photonic integrated circuits.

[0067] After providing a socket 320 and at least one optical waveguide 110 for the interposer 100, and providing at least one optoelectronic device 410, such as a photonic integrated circuit, at least one light receiving/emitting element 420, and at least one optical channel 430, for the substrate 400, the interposer 100 and the substrate 400 must be aligned so that light can be coupled between the at least one optical waveguide 110 and the at least one optoelectronic device 410 with low loss.

[0068] Such as Picture 9 As shown, you can use as Picture 9 With the reference shown, each substrate/chip 400 is aligned relative to the interposer 100 to which it must be individually coupled to complete the alignment of the structure. The interposer 100 with the socket 320 may include a plurality of fiducials e1, e2, and e3, and the substrate 400 including the fiducials d1, d2, and d3 is aligned therewith. The alignment of the fiducials d1, d2, and d3 of the substrate/chip 400 and the fiducials e1, e2, and e3 of the interposer 100 ensures that the light receiving/transmitting elements of the substrate/chip 400 are correctly aligned with the area 102 that provides the TIR.

[0069] Another method of manufacturing an arrangement for coupling at least one optical fiber 200 to at least one optoelectronic device 410 is described in Picture 10 with 11 Shown in. according to Picture 10 with 11 The method provides a first wafer 1000, which includes at least one first reference 1100 and a plurality of inserters 100, such as Picture 11 Shown on the left. In addition, a second wafer 2000 is provided, which includes at least one second reference 2100 and a plurality of substrates 400, such as Picture 11 Shown on the right.

[0070] according to Picture 10 with 11 In the manufacturing method, the first wafer 1000 and the second wafer 2000 are aligned by means of at least one first reference 1100 and at least one second reference 2100, so that a corresponding one of the plurality of interposers 100 of the first wafer 1000 and the first A corresponding one of the plurality of substrates 400 of the two wafer 2000 is arranged so as to couple from at least one optical waveguide 110 of a corresponding one of the plurality of interposers 100 at the second end 112 of the at least one optical waveguide 110 The outgoing light is coupled to at least one light receiving/emitting element 420 of a corresponding one of the plurality of substrates 400, and/or from at least one light receiving/emitting element of a corresponding one of the plurality of substrates 400 The light coupled by 420 is coupled to at least one optical waveguide 110 of a corresponding one of the plurality of interposers 100 at the second end 112 of the at least one optical waveguide 110. From the wafer stack including the first and second wafers, a corresponding one of the pair of interposers 100 and a corresponding one of the plurality of substrates 400 are singulated.

[0071] And as Picture 9 The individual alignment and attachment of the components shown are contrary to Picture 10 with 11 The alternative method described provides alignment of components at the wafer level. Both the interposer 100 and the substrate 400 can be manufactured on a wafer level, which includes manufacturing steps such as masking, ion exchange, laser writing, and etching. The fabrication of optical waveguides and TIR structures is accomplished through wafer-level processes, such as ion exchange processes or laser writing processes. When the first and second wafers 1000 and 2000 have been completed, the entire wafer can be aligned and connected with high precision, such as Picture 10 Shown. This ensures that all components on the two wafers are aligned with each other. Since a large number of components are aligned in one step, this is a very low cost process.

[0072] The arrangement for coupling at least one optical fiber 200 to at least one optoelectronic device 410 includes an interposer 100 including at least one optical waveguide 110 and a substrate 400 including at least one optoelectronic device 410, such as a photonic integrated circuit. This arrangement has several advantages. One of the advantages is that it can be extended to multiple fiber couplings, because all components can be adapted to structures with more than one optical path. Although the optical connector 310 is the only element that explicitly includes an optical fiber, both the interposer 100 and the substrate 400 may include multiple waveguides for receiving (RX) and transmitting (TX) processes.

[0073] This arrangement allows passive alignment through a mechanical interface including a connector 310, such as an MT- (physical contact) or MXC-like (expanded beam) connector, and a socket 320. Since the socket 320 allows the connector 310 to be inserted and removed without having to break and realign any adhesive, the socket 320 allows repeated mating. The TIR element 102 is adapted to the incident angle of the substrate, for example an angle of about 8°. The polarization of light from at least one optical fiber to the substrate 400 is controlled in the interposer 100, thereby simplifying the grating design on the chip. It is possible to design all elements of the arrangement without knowing the precise fiber design. The interposer provides a universal interface for coupling multiple substrates of photonic integrated circuits. Different photonic integrated circuits can be connected using the same interposer, without the need to align the fibers separately. This arrangement allows the fiber to be coupled to almost any location on the chip, not just the edge.