Photonic integrated circuit chip

Abstract

The invention relates to a photonic integrated circuit chip. The photonic integrated circuit chip has a blank area, and includes a grating coupler array, an optical detector array, an optical modulator module, a plurality of optical waveguides, and a plurality of pads. The light detector array is used for converting light signals from the grating coupler array into electric signals. The light modulator module is used for modulating the light beam from the grating coupler array, so that light with specific wavelength in the light beam is output from the grating coupler array. The optical modulator module and the optical detector array are coupled with the grating coupler array through the optical waveguide. The bonding pad is electrically connected to the light modulator module and the light detector array. The grating coupler array, the optical detector array, the optical modulator module, the optical waveguide and the welding pad are arranged around the blank area. Therefore, the photon integrated circuit chip integrates the signal receiving end and the signal transmitting end into one module through simple design.

Description

Technical Field

[0001] The present invention relates to an integrated circuit chip, and in particular to a photonic integrated circuit chip. Background Art

[0002] In recent years, with the rapid growth of data transmission volume, the demand for network bandwidth and transmission speed has also increased, and the global deployment of communication systems continues to grow. In the current fiber-optic communication system, the mainstream uses pluggable fiber modules (Pluggable module), such as SFP, QSFP and other modules. This type of module is first packaged by various scattered optical components to form an optical sub-assembly (OSA), and then this component is packaged with a printed circuit board (PCB) to form a module. The mainstream manufacturing model of this module has two major bottlenecks: the module requires many components and the production process is complicated; and the optical components need to set up a complex coupling system to complete the optical path connection.

[0003] The current industry trend is to solve the above bottlenecks mainly through silicon photonics technology. Silicon photonics technology uses the mature CMOS process of the semiconductor industry to produce integrated circuits (IC) technology for the production of micron-level optoelectronic components and complete the connection of optoelectronic components on the chip.

[0004] However, this chip encountered two problems when integrating with the PCB. First, in the configuration of the modulator and the pad, the pads are too concentrated when there are many pads, which means that the wire bonding design must be bonded to the PCB in a high-low staggered manner, increasing the risk of gold wire collision. Second, the narrow spacing of the modulator leads to different lengths of gold wires connecting the PCB high-speed lines and the chip channels. Since the length of the gold wire affects the inductance value, the same modulator design has performance differences due to different package designs.

[0005] In addition, in the modulator design provided by the foundry, due to volume limitations, no impedance matching circuit is designed at the input end. If there is any impedance discontinuity in the transmission path, most of the input signal energy will be reflected. The energy will be repeatedly reflected between the discontinuity point and the modulator, eventually causing optical signal jitter and signal distortion.

[0006] In summary, this chip has the following problems. The components of the non-silicon photonic system module are complex, and the assembly process is complicated. The micro-ring modulator needs to establish a stable temperature control mechanism. The wire density when the chip is packaged with the PCB cannot be too high. The impedance of the micro-ring modulator components is not matched, resulting in test results that are not as expected. Summary of the invention

[0007] The present invention provides a photonic integrated circuit (PIC) chip, which has a better design in the layout of components and circuits.

[0008] One embodiment of the present invention provides a photonic integrated circuit chip. The photonic integrated circuit chip has a blank area and includes a grating coupler array, a photodetector array, an optical modulator module, a plurality of optical waveguides, and a plurality of pads. The grating coupler array is suitable for receiving a light beam and an optical signal from the outside. The photodetector array is coupled to the grating coupler array to convert the optical signal from the grating coupler array into an electrical signal. The optical modulator module is coupled to the grating coupler array to modulate the light beam from the grating coupler array so that light of a specific wavelength in the light beam is output from the grating coupler array. The optical modulator module and the photodetector array are coupled to the grating coupler array via an optical waveguide. The pad is electrically connected to the optical modulator module and the photodetector array. The grating coupler array, the photodetector array, the optical modulator module, the optical waveguide, and the pad are arranged around the blank area.

[0009] One embodiment of the present invention provides a photonic integrated circuit chip. The photonic integrated circuit chip has a blank area and includes a grating coupler array, an optical modulator module, a plurality of optical waveguides, a plurality of heaters and a plurality of pads. The grating coupler array is suitable for receiving a light beam from the outside. The optical modulator module is coupled to the grating coupler to modulate the light beam from the grating coupler array so that light of a specific wavelength in the light beam is output from the grating coupler array. The optical modulator module is coupled to the grating coupler array by an optical waveguide. The heater is electrically connected to the optical modulator module. The pad is electrically connected to the optical modulator module and the heater. The grating coupler array, the optical modulator module, the optical waveguide, the heater and the pad are arranged around the blank area. The optical modulator module includes a first light detector array, an optical modulator array and a second light detector array. The light beam includes a first light beam and a second light beam. The first light beam is transmitted to the first light detector array, and the second light beam is transmitted to the optical modulator array. The optical modulator array receives and modulates the second light beam to generate a third light beam. The third light beam includes a fourth light beam and a fifth light beam, the fourth light beam is transmitted to the second light detector array, and the fifth light beam is transmitted to the grating coupler array. The heater is arranged in the light modulator array. The pad is suitable for being electrically connected to the controller so that the controller obtains the light intensity of the first light beam and the light intensity of the fourth light beam. The controller adjusts the light intensity of the third light beam by regulating the temperature of the light modulator array by the heater according to the ratio between the light intensity of the fourth light beam and the light intensity of the first light beam.

[0010] Based on the above, in a photonic integrated circuit chip of an embodiment of the present invention, the photodetector array is designed as a signal receiving end: coupled with the grating coupler array to convert the optical signal from the grating coupler array into an electrical signal; the optical modulator module is designed as a signal transmitting end: coupled with the grating coupler array to modulate the light beam from the grating coupler array so that the light of a specific wavelength in the light beam is output from the grating coupler array. Therefore, the photonic integrated circuit chip integrates the signal receiving end and the signal transmitting end into one module by a simple design.

[0011] Furthermore, in a photonic integrated circuit chip of an embodiment of the present invention, the controller obtains the light intensity of the first light beam from the first light detector array and the light intensity of the fourth light beam from the second light detector array through the bonding pad. The controller adjusts the light intensity of the third light beam by regulating the temperature of the light modulator array through the heater according to the ratio between the light intensity of the fourth light beam and the light intensity of the first light beam. Therefore, the light modulator module is combined with the heater to form a monitoring and compensation system, which can increase the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1A is a schematic diagram of a photonic integrated circuit chip according to an embodiment of the present invention;

[0013] Figure 1B is a block diagram of the connection relationship between various components of a photonic integrated circuit chip according to an embodiment of the present invention;

[0014] Figure 2 yes Figure 1A A magnified view of the grating coupler array;

[0015] Figure 3 yes Figure 1A A magnified view of the photodetector array;

[0016] Figure 4 yes Figure 1A an enlarged view of a first photodetector array;

[0017] Figure 5 yes Figure 1A A magnified view of the light modulator array in FIG.

[0018] Figure 6 is a schematic diagram of an example of an optical modulator in an optical modulator array of a photonic integrated circuit chip according to an embodiment of the present invention;

[0019] Figure 7 is an enlarged view of a photonic integrated circuit chip in a grating coupler array according to another embodiment of the present invention;

[0020] Figure 8 yes Figure 7Schematic diagram of coupling with optical fiber array;

[0021] Fig. 9 The figure is a schematic diagram of connecting a photonic integrated circuit chip to a circuit board according to an embodiment of the present invention.

[0022]

Description of the accompanying drawings

[0023] 10. Photonic integrated circuit chips;

[0024] 20. Substrate;

[0025] 100. Grating coupler array;

[0026] 102. a first grating coupler;

[0027] 104. A second grating coupler;

[0028] 106. a third grating coupler;

[0029] 108. a fourth grating coupler;

[0030] 110. a fifth grating coupler;

[0031] 200, photodetector array;

[0032] 202, light detector;

[0033] 300. Optical modulator module;

[0034] 310. A first photodetector array;

[0035] 312. a first light detector;

[0036] 320, optical modulator array;

[0037] 322. Optical modulator;

[0038] 330. A second photodetector array;

[0039] 332. a second light detector;

[0040] 400, optical waveguide;

[0041] 500, welding pad;

[0042] 510, first welding pad;

[0043] 520, second welding pad;

[0044] 530, third welding pad;

[0045] 540, fourth welding pad;

[0046] 550, fifth welding pad;

[0047] 600, optical splitter;

[0048] 700, a first directional coupler;

[0049] 800, heater;

[0050] 900, second directional coupler;

[0051] 1000, impedance matching device;

[0052] 1100, first alignment key;

[0053] 1200, second alignment key;

[0054] 1300, third pair key;

[0055] AL, alignment beam;

[0056] BW, wire bonding;

[0057] CT, controller;

[0058] DS, driving signal;

[0059] EA, blank area;

[0060] EP, electrical contact;

[0061] ES, electrical signal;

[0062] FB, fiber array;

[0063] G1, first ground pad;

[0064] G2, second ground pad;

[0065] G3, third ground pad;

[0066] L, beam;

[0067] L1, first beam;

[0068] L2, second beam;

[0069] L3, third beam;

[0070] L4, fourth beam;

[0071] L5, fifth beam;

[0072] LS, light signal;

[0073] OL, output beam;

[0074] PCB, circuit board;

[0075] S1, first side;

[0076] S2, second side;

[0077] S3, third side;

[0078] S4, fourth side. DETAILED DESCRIPTION

[0079] Figure 1A is a schematic diagram of a photonic integrated circuit chip according to an embodiment of the present invention. Figure 1B This is a block diagram of the connection relationship between various components of a photonic integrated circuit chip according to an embodiment of the present invention. Figure 1A and Figure 1B One embodiment of the present invention provides a photonic integrated circuit chip 10. The photonic integrated circuit chip 10 has an empty area EA and includes a substrate 20, a grating coupler array 100, a photodetector array 200, an optical modulator module 300, a plurality of optical waveguides 400, and a plurality of pads 500. The grating coupler array 100, the photodetector array 200, the optical modulator module 300, the optical waveguide 400, and the pads 500 are all disposed on the substrate 20. The substrate 20 may be a circuit board, but the present invention is not limited thereto.

[0080] In this embodiment, the grating coupler array 100 is suitable for receiving a light beam L and a light signal LS from the outside. The photodetector array 200 is coupled to the grating coupler array 100 to convert the light signal LS from the grating coupler array 100 into an electrical signal ES. The optical modulator module 300 is coupled to the grating coupler array 100 to modulate the light beam L from the grating coupler array 100 so that a light of a specific wavelength (e.g., a fifth light beam L5) in the light beam L is output from the grating coupler array 100. The optical modulator module 300 and the photodetector array 200 are coupled to the grating coupler array 100 via an optical waveguide 400. The pad 500 is electrically connected to the optical modulator module 300 and the photodetector array 200. The grating coupler array 100, the photodetector array 200, the optical modulator module 300, the optical waveguide 400, and the pad 500 are all disposed around the blank area EA.

[0081] Figure 2 yes Figure 1A A magnified view of the grating coupler array. Figure 1A and Figure 2 In detail, Figure 1A For example, the blank area EA has a first side S1, a second side S2, a third side S3 and a fourth side S4. The second side S2 is relative to the first side S1. The fourth side S4 is relative to the third side S3. The third side S3 is adjacent to the first side S1 and the second side S2, and the fourth side S4 is adjacent to the first side S1 and the second side S2.

[0082] In this embodiment, the grating coupler array 100 is disposed beside the first side S1 of the blank area EA, and includes a first grating coupler 102, a plurality of second grating couplers 104, a plurality of third grating couplers 106, a plurality of fourth grating couplers 108, and a fifth grating coupler 110 arranged in sequence along the first side S1. The grating couplers can be used to convert the direction of light from vertical to horizontal or from horizontal to vertical.

[0083] In this embodiment, the first grating coupler 102 is coupled to the fifth grating coupler 110 via one of the optical waveguides 400 to form a self-loop optical path. One of the first grating coupler 102 and the fifth grating coupler 110 is adapted to receive the alignment beam AL (from the outside). The alignment beam AL is transmitted to the other of the first grating coupler 102 and the fifth grating coupler 110 via the one of the optical waveguides 400 to generate the output beam OL. The ratio between the output beam OL and the alignment beam AL determines the optical fiber array (e.g. Figure 8 The coupling efficiency between the optical fiber array FB) and the grating coupler array 100.

[0084] Figure 3 yes Figure 1A A magnified view of the photodetector array in Figure 2. Figure 1A , Figure 1B , Figure 2 and Figure 3 In this embodiment, the photodetector array 200 is disposed at the second side S2 of the blank area EA relative to the first side S1. The photodetector array 200 includes a plurality of photodetectors 202 arranged in an array along the second side S2. The second grating couplers 104 are respectively coupled to the photodetectors 202. The number of the second grating couplers 104 is equal to the number of the photodetectors 202.

[0085] In this embodiment, the pads 500 include a plurality of first pads 510, a plurality of second pads 520, a first ground pad G1, a plurality of third pads 530, a plurality of fourth pads 540, a second ground pad G2, a plurality of fifth pads 550, and a third ground pad G3. The pads 500 are dispersed around the blank area EA and are arranged in an array along the third side S3, the second side S2, and the fourth side S4.

[0086] In this embodiment, the first pad 510 is disposed beside the second side S2 and beside the photodetector array 200. The first pad 510 is electrically connected to the photodetector 202 and is used to output the electrical signal ES from the photodetector 202.

[0087] Figure 4 yes Figure 1A, an enlarged view of the first photodetector array. Figure 1A , Figure 1B , Figure 2 and Figure 4 In this embodiment, the optical modulator module 300 includes a first light detector array 310, a light modulator array 320, and a second light detector array 330. The first light detector array 310 is disposed next to the third side S3 of the blank area EA. The light modulator array 320 is disposed next to the second side S2 of the blank area EA. The second light detector array 330 is disposed next to the fourth side S4 of the blank area EA. (One end) of the first light detector array 310 is coupled to the third grating coupler 106, (the other end) of the first light detector array 310 is coupled to (one end) of the light modulator array 320, (the other end) of the light modulator array 320 is coupled to (one end) of the second light detector array 330, and (the other end) of the second light detector array 330 is coupled to the fourth grating coupler 108. As Figure 1B As shown, the light beam L includes a first light beam L1 and a second light beam L2. The first light beam L1 of the light beam L from the third grating coupler 106 is transmitted to the first light detector array 310, and the second light beam L2 of the light beam L from the third grating coupler 106 is transmitted to the light modulator array 320. The light modulator array 320 receives and modulates the second light beam L2 to generate a third light beam L3. The third light beam L3 includes a fourth light beam L4 and a fifth light beam L5. The fourth light beam L4 of the third light beam L3 from the light modulator array 320 is transmitted to the second light detector array 330, and the fifth light beam L5 of the third light beam L3 from the light modulator array 320 is transmitted to the fourth grating coupler 108.

[0088] In the present embodiment, the photonic integrated circuit chip 10 further includes a plurality of beam splitters 600. The beam splitter 600 may be a 1-to-2 multi-mode interference coupler, but the present invention is not limited thereto. The beam splitter 600 is disposed next to the third side S3. The first light detector array 310 includes a plurality of first light detectors 312. The first light detector 312 is coupled to the third grating coupler 106 via the beam splitter 600. The light beam L from the third grating coupler 106 is first transmitted to the beam splitter 600 and then to the first light detector array 310. The number of the third grating couplers 106 is equal to the number of the beam splitters 600, and the number of the first light detectors 312 is greater than the number of the beam splitters 600.

[0089] In the present embodiment, the photonic integrated circuit chip 10 further includes a plurality of first directional couplers (Directional Couplers, DC) 700. The first directional couplers 700 are disposed next to the third side S3. Each first directional coupler 700 is correspondingly disposed next to one of the first light detectors 312. One end of each first directional coupler 700 is coupled to the beam splitter 600, and the other end and the further end of each first directional coupler are respectively coupled to the corresponding first light detector 312 and the light modulator array 320. The first directional coupler 700 is used to split the light beam L into the first light beam L1 and the second light beam L2. The light intensity ratio of the first light beam L1 and the second light beam L2 after the splitting is, for example, 5:95, but the present invention is not limited thereto.

[0090] In this embodiment, the second pads 520 and the first ground pads G1 are disposed beside the first photodetector array 310. The second pads 520 are electrically connected to the first photodetectors 312, respectively, and the first ground pads G1 are electrically connected to the first photodetectors 312. The number of the second pads 520 is equal to the number of the first photodetectors 312. The second pads 520 and the first ground pads G1 are suitable for being electrically connected to a controller CT, such as Figure 1B As shown, the controller CT can obtain the light intensity of the first light beam L1.

[0091] In one embodiment, the controller CT includes, for example, a central processing unit (CPU), a microprocessor (microprocessor), a digital signal processor (DSP), a programmable controller, a programmable logic device (PLD) or other similar devices or a combination of these devices, and the present invention is not limited thereto. In addition, in one embodiment, each function of the controller CT can be implemented as a plurality of program codes. These program codes are stored in a memory unit and executed by the controller CT. Alternatively, in one embodiment, each function of the controller CT can be implemented as one or more circuits. The present invention is not limited to the implementation of each function of the controller CT by software or hardware.

[0092] Figure 5 yes Figure 1A A magnified view of the light modulator array. Figure 6 FIG. 1 is a schematic diagram of an example of an optical modulator in an optical modulator array of a photonic integrated circuit chip according to an embodiment of the present invention. Figure 1A , Figure 1B , Figure 2 , Figure 5 and Figure 6In this embodiment, the photonic integrated circuit chip 10 further includes a plurality of heaters 800. The heaters 800 are disposed next to the second side S2. The light modulator array 320 includes a plurality of light modulators 322, and the heaters 800 are disposed next to the light modulators 322. In one embodiment, each heater 800 and its corresponding light modulator 322 overlap each other on the substrate 20. Figure 6 shown.

[0093] In this embodiment, the optical modulator 322 may be an electro-optic modulator, such as Figure 6 The third pad 530 is disposed beside the light modulator array 320, electrically connected to the light modulator 322, and used to receive a driving signal DS (from the outside) to drive the light modulator 322 to modulate the second light beam L2 to generate the third light beam L3.

[0094] In the present embodiment, the fourth pad 540 and the second ground pad G2 are arranged beside the fourth side S4 of the blank area EA. The fourth pads 540 are electrically connected to the heater 800, respectively, and the second ground pad G2 is electrically connected to the heater 800. The fourth pad 540 and the second ground pad G2 are suitable for being electrically connected to the controller CT, so that the controller CT adjusts the temperature of the optical modulator 322 by the heater 800 to adjust the light intensity of the third light beam L3. Among them, the number of heaters 800 is equal to the number of optical modulators 322, and is equal to the number of fourth pads 540. In addition, since the signal for regulating the heater 800 is not a high-speed signal, the position of the fourth pad 540 and the second ground pad G2 connected to the heater 800 is designed on the fourth side S4 instead of the second side S2, which can reduce the problem of too high density of the pads 500 on the second side S2.

[0095] In addition, in this embodiment, the photonic integrated circuit chip 10 further includes a plurality of impedance matchers 1000, which are respectively disposed beside the optical modulator 322 and are respectively electrically connected to the optical modulator 322. The impedance matcher 1000 is used to match the impedance value of the optical modulator 322. The impedance matcher 1000 is, for example, a matching resistor. In one embodiment, the impedance matcher 1000 may include a matching resistor and a bonding wire electrically connected to the optical modulator 322.

[0096] Please refer to Figure 1A , Figure 1B and Figure 2In this embodiment, the second optical detector array 330 includes a plurality of second optical detectors 332. The fourth grating couplers 108 are respectively coupled to the second optical detectors 332. The number of the fourth grating couplers 108 is equal to the number of the second optical detectors 332.

[0097] In the present embodiment, the photonic integrated circuit chip 10 further includes a plurality of second directional couplers 900. Similar to the first directional coupler 700, the second directional coupler 900 is disposed next to the fourth side S4. Each second directional coupler 900 is correspondingly disposed next to one of the second light detectors 332. One end of each second directional coupler 900 is coupled to the light modulator array 320, and the other end and the further end of each second directional coupler 900 are respectively coupled to the corresponding second light detector 332 and the fourth grating coupler 108. The second directional coupler 900 is used to split the third light beam L3 from the light modulator array 320 into the fourth light beam L4 and the fifth light beam L5. The light intensity ratio of the fourth light beam L4 and the fifth light beam L5 after the splitting is, for example, 5:95, but the present invention is not limited thereto.

[0098] In this embodiment, the fifth pad 550 and the third ground pad G3 are disposed beside the second light detector array 330. The fifth pads 550 are electrically connected to the second light detectors 332, respectively, and the third ground pad G3 is electrically connected to the second light detector 332. The number of the fifth pads 550 is equal to the number of the second light detectors 332. The fifth pad 550 and the third ground pad G3 are suitable for being electrically connected to the controller CT, so that the controller CT obtains the light intensity of the fourth light beam L4.

[0099] In this embodiment, the controller CT adjusts the light intensity of the third light beam L3 according to the ratio between the light intensity of the fourth light beam L4 and the light intensity of the first light beam L1 .

[0100] Based on the above, in one embodiment of the present invention, the photonic integrated circuit chip 10 includes a grating coupler array 100, a light detector array 200, an optical modulator module 300, an optical waveguide 400 and a pad 500. Among them, the light detector array 200 is designed as a signal receiving end: coupled with the grating coupler array 100 to convert the optical signal LS from the grating coupler array 100 into an electrical signal ES. The optical modulator module 300 is designed as a signal transmitting end: coupled with the grating coupler array 100 to modulate the light beam L from the grating coupler array 100 so that the light of a specific wavelength in the light beam L is output from the grating coupler array 100. Therefore, the photonic integrated circuit chip 10 integrates the signal receiving end and the signal transmitting end into one module through a simple design. Among them, Figure 1AThe light detector array 200 is shown to include four groups of light detectors 202, and the light modulator module 300 includes four groups of light modulators 322. That is, the light detector array 200 forms a four-channel signal receiving end, and the light modulator module 300 forms a four-channel signal transmitting end. However, the present invention does not limit the number of light detectors 202 and light modulators 322.

[0101] Furthermore, in one embodiment, the photonic integrated circuit chip 10 further includes a heater 800. Moreover, the optical modulator module 300 includes a first optical detector array 310, an optical modulator array 320, and a second optical detector array 330. The controller CT obtains the light intensity of the first light beam L1 from the first optical detector array 310 and the light intensity of the fourth light beam L4 from the second optical detector array 330 through the pad 500. The controller CT adjusts the temperature of the optical modulator array 320 through the heater 800 according to the ratio between the light intensity of the fourth light beam L4 and the light intensity of the first light beam L1, so as to adjust the light intensity of the third light beam L3, so that the optical modulator array 320 adjusts the wavelength range of the light passing through, thereby allowing the fifth light beam L5 to output the correct wavelength. In other words, by monitoring the light intensity of the first light beam L1 at the input end and the light intensity of the fourth light beam L4 at the output end, it is determined whether the fifth light beam L5 meets the correct wavelength. When the wavelength of the fifth light beam L5 is not the correct wavelength, for example, due to a change in the system ambient temperature, the temperature of the light modulator array 320 is adjusted by the heater 800 to control the third light beam L3 to a corresponding light intensity, so that the fifth light beam L5 can output the correct wavelength. Therefore, the light modulator module 300 and the heater 800 form a monitoring and compensation system, which can increase the stability of the system.

[0102] In addition, in one embodiment, the photonic integrated circuit chip 10 further includes a plurality of impedance matchers 1000 electrically connected to the optical modulator 322. Therefore, the configuration of the impedance matcher 1000 avoids the problem of input signal energy being reflected due to impedance mismatch, thereby optimizing system performance.

[0103] Figure 7 is an enlarged view of a photonic integrated circuit chip in a grating coupler array according to another embodiment of the present invention. Figure 7 In this embodiment, the photonic integrated circuit chip further includes a plurality of first alignment keys 1100, a plurality of second alignment keys 1200, and a plurality of third alignment keys 1300 disposed beside the first side S1 of the blank area EA. The first alignment keys 1100 and the third alignment keys 1300 are arranged in a 2×2 matrix, and the second alignment keys 1200 are arranged in a 1×12 matrix along the first side S1.

[0104] In this embodiment, the first alignment key 1100 is disposed at one end of the grating coupler array 100, and the third alignment key 1300 is disposed at the other end of the grating coupler array 100 relative to the one end. The second alignment key 1200 is disposed between the first alignment key 1100 and the third alignment key 1300, and aligns the first grating coupler 102, the second grating coupler 104, the third grating coupler 106, the fourth grating coupler 108, and the fifth grating coupler 110, respectively.

[0105] Figure 8 yes Figure 7 Schematic diagram of coupling to fiber array. Please refer to Figure 8 In this embodiment, the grating coupler array 100 is suitable for coupling with an (external) optical fiber array FB. The optical fiber array FB can be clamped in the glass member GL. The grating coupler array 100 receives the light beam L, the optical signal LS and the alignment light beam AL through the optical fiber array FB, and outputs the output light beam OL. Figure 2 As shown. The first alignment key 1100, the second alignment key 1200 and the third alignment key 1300 are suitable for assisting the coupling of the optical fiber array FB and the grating coupler array 100 when the grating coupler array 100 is coupled to the optical fiber array FB. Among them, the ratio between the output light beam OL and the alignment light beam AL determines the coupling efficiency between the optical fiber array FB and the grating coupler array 100. In other words, an optical method (such as camera shooting) is used to preliminarily determine whether the optical fiber array FB is correctly aligned on the alignment key, and then the self-loop optical path formed by the coupling of the first grating coupler 102 and the fifth grating coupler 110 is used to confirm whether the optical fiber array FB is coupled in the correct position. Therefore, compared with the traditional method of having to compare each input end and output end, the photonic integrated circuit chip of the embodiment of the present invention can simplify the alignment process.

[0106] Fig. 9 is a schematic diagram of a photonic integrated circuit chip connected to a circuit board according to an embodiment of the present invention. Fig. 9 In this embodiment, the photonic integrated circuit chip 10 is suitable for being electrically connected to a circuit board PCB. The photonic integrated circuit chip 10 is electrically connected to the electrical pads EP of the circuit board PCB via the pads 500 to output the electrical signal ES and receive the driving signal DS for driving the optical modulator module 300. In one embodiment, the circuit board PCB is electrically connected to the controller CT or the circuit board PCB includes the controller CT. Therefore, the controller CT can obtain the light intensity of the first light beam L1 from the first light detector array 310 and the light intensity of the fourth light beam L4 from the second light detector array 330, respectively, so that the controller CT can adjust the light intensity of the third light beam L3 by the heater 800 according to the ratio between the light intensity of the fourth light beam L4 and the light intensity of the first light beam L1.

[0107] Based on the above, in the photonic integrated circuit chip 10 of one embodiment of the present invention, the positions of the bonding pads 500 are designed to be dispersed around the blank area EA, so that the bonding wires BW can simply connect the bonding pads 500 of the photonic integrated circuit chip 10 with the electrical contacts EP of the circuit board PCB, thereby reducing the difficulty of integrating the photonic integrated circuit chip 10 with the circuit board PCB. Fig. 9 As shown, the lengths of adjacent bonding wires BW are substantially the same, and there is no staggered condition. In addition, the bonding pad 500 includes a first grounding pad G1, a second grounding pad G2, and a third grounding pad G3 designed to be commonly grounded, so the number of bonding pads 500 can be reduced, thereby reducing the density of the bonding pads 500. In this way, the placement spacing of components can be increased, and space for wire bonding can be provided to avoid electrical loss caused by packaging that affects component characteristics.

[0108] In summary, in one embodiment of the present invention, a photonic integrated circuit chip includes a grating coupler array, a photodetector array, an optical modulator module, an optical waveguide, and a pad. Among them, the photodetector array is designed as a signal receiving end: coupled with the grating coupler array to convert the optical signal from the grating coupler array into an electrical signal. The optical modulator module is designed as a signal transmitting end: coupled with the grating coupler array to modulate the light beam from the grating coupler array so that the light of a specific wavelength in the light beam is output from the grating coupler array. Therefore, the photonic integrated circuit chip integrates the signal receiving end and the signal transmitting end into one module through a simple design.

[0109] Furthermore, in one embodiment, the photonic integrated circuit chip also includes a heater. Moreover, the optical modulator module includes a first light detector array, an optical modulator array, and a second light detector array. The controller obtains the light intensity of the first light beam from the first light detector array and the light intensity of the fourth light beam from the second light detector array through the pad. The controller adjusts the light intensity of the third light beam by regulating the temperature of the optical modulator array through the heater according to the ratio between the light intensity of the fourth light beam and the light intensity of the first light beam. By monitoring the light intensity of the first light beam at the input end and the light intensity of the fourth light beam at the output end, it is determined whether the fifth light beam meets the correct wavelength, and then the temperature of the optical modulator array is regulated by the heater to control the third light beam at the corresponding light intensity so that the fifth light beam is at the correct wavelength. Therefore, the optical modulator module is combined with the heater to form a monitoring and compensation system, which can increase the stability of the system.

Claims

1. A photonic integrated circuit chip, characterized in that: Having a blank area, the photonic integrated circuit chip comprises: a grating coupler array, adapted to receive light beams and optical signals from the outside; a photodetector array coupled to the grating coupler array and configured to convert the optical signal from the grating coupler array into an electrical signal; an optical modulator module coupled to the grating coupler array and configured to modulate the light beam from the grating coupler array so that light of a specific wavelength in the light beam is output from the grating coupler array; a plurality of optical waveguides, wherein the optical modulator module and the optical detector array are coupled to the grating coupler array via the plurality of optical waveguides; and A plurality of pads electrically connected to the light modulator module and the light detector array, The grating coupler array, the light detector array, the light modulator module, the plurality of light waveguides and the plurality of pads are arranged around the blank area.

2. The photonic integrated circuit chip according to claim 1, characterized in that: The grating coupler array is arranged beside the first side of the blank area and includes a first grating coupler, a plurality of second grating couplers, a plurality of third grating couplers, a plurality of fourth grating couplers and a fifth grating coupler which are arranged in an array in sequence along the first side.

3. The photonic integrated circuit chip according to claim 2, characterized in that: The first grating coupler is coupled to the fifth grating coupler via one of the plurality of optical waveguides to form a self-looping optical path. One of the first grating coupler and the fifth grating coupler is suitable for receiving an aligned light beam, and the aligned light beam is transmitted to the other one of the first grating coupler and the fifth grating coupler through the one of the plurality of optical waveguides to generate an output light beam.

4. The photonic integrated circuit chip according to claim 2, characterized in that: The light detector array is disposed beside a second side of the blank area relative to the first side, and the light detector array includes a plurality of light detectors arranged in an array along the second side. wherein the plurality of second grating couplers are respectively coupled to the plurality of photodetectors, The number of the plurality of second grating couplers is equal to the number of the plurality of photodetectors.

5. The photonic integrated circuit chip according to claim 4, characterized in that: The plurality of bonding pads include a plurality of first bonding pads, which are arranged beside the photodetector array, electrically connected to the plurality of photodetectors, and used for outputting the electrical signals from the plurality of photodetectors.

6. The photonic integrated circuit chip according to claim 2, characterized in that: The optical modulator module includes a first optical detector array, an optical modulator array and a second optical detector array. The first photodetector array is arranged beside a third side of the blank area adjacent to the first side, the light modulator array is arranged beside a second side of the blank area relative to the first side, and the second side is adjacent to the third side, and the second photodetector array is arranged beside a fourth side of the blank area adjacent to the first side and the second side. wherein the plurality of third grating couplers are coupled to one end of the first light detector array, the other end of the first light detector array is coupled to one end of the light modulator array, the other end of the light modulator array is coupled to one end of the second light detector array, and the other end of the second light detector array is coupled to the plurality of fourth grating couplers, The light beam includes a first light beam and a second light beam, the first light beam among the light beams from the plurality of third grating couplers is transmitted to the first light detector array, and the second light beam among the light beams from the plurality of third grating couplers is transmitted to the light modulator array, and the light modulator array receives and modulates the second light beam to generate a third light beam, The third light beam includes a fourth light beam and a fifth light beam, the fourth light beam in the third light beam from the light modulator array is transmitted to the second light detector array, and the fifth light beam in the third light beam from the light modulator array is transmitted to the plurality of fourth grating couplers.

7. The photonic integrated circuit chip according to claim 6, characterized in that: The method further comprises a plurality of beam splitters, wherein the plurality of beam splitters are disposed beside the third side, wherein the first photodetector array comprises a plurality of first photodetectors, and the plurality of first photodetectors are coupled to the plurality of third grating couplers via the plurality of beam splitters, The light beams from the plurality of third grating couplers are first transmitted to the plurality of beam splitters and then to the plurality of first light detectors. The number of the third grating couplers is equal to the number of the beam splitters, and the number of the first photodetectors is greater than the number of the beam splitters.

8. The photonic integrated circuit chip according to claim 7, characterized in that: The optical modulator array further comprises a plurality of first directional couplers, wherein the plurality of first directional couplers are disposed beside the third side, wherein each first directional coupler is correspondingly disposed beside one of the plurality of first light detectors, one end of each first directional coupler is coupled to the plurality of light splitters, and the other end and the further end of each first directional coupler are respectively coupled to the corresponding first light detector and the light modulator array, The plurality of first directional couplers are used to separate the light beam into the first light beam and the second light beam.

9. The photonic integrated circuit chip according to claim 7, characterized in that: The plurality of pads include a plurality of second pads and a first ground pad, the plurality of second pads and the first ground pad are arranged beside the first photodetector array, the plurality of second pads are electrically connected to the plurality of first photodetectors respectively, and the first ground pad is electrically connected to the plurality of first photodetectors, wherein the number of the plurality of second pads is equal to the number of the plurality of first light detectors, The plurality of second pads and the first ground pad are suitable for being electrically connected to a controller so that the controller can obtain the light intensity of the first light beam.

10. The photonic integrated circuit chip according to claim 6, characterized in that: It further includes a plurality of heaters, which are disposed beside the second side, wherein the light modulator array includes a plurality of light modulators, and the plurality of heaters are correspondingly disposed beside the plurality of light modulators.

11. The photonic integrated circuit chip according to claim 10, characterized in that: The plurality of pads include a plurality of third pads, a plurality of fourth pads and a second ground pad. The plurality of third pads are arranged beside the optical modulator array, electrically connected to the plurality of optical modulators, and used to receive a driving signal to drive the plurality of optical modulators to modulate the second light beam to generate the third light beam.

12. The photonic integrated circuit chip according to claim 11, characterized in that: The plurality of fourth pads and the second ground pad are disposed beside a fourth side of the blank area, the plurality of fourth pads are electrically connected to the plurality of heaters, respectively, and the second ground pad is electrically connected to the plurality of heaters. wherein the plurality of fourth pads and the second ground pad are suitable for being electrically connected to a controller, so that the controller controls the temperature of the plurality of light modulators by means of the plurality of heaters to adjust the light intensity of the third light beam, The number of the plurality of heaters is equal to the number of the plurality of light modulators and is also equal to the number of the plurality of fourth pads.

13. The photonic integrated circuit chip according to claim 10, characterized in that: It further includes a plurality of impedance matchers, which are respectively arranged beside the plurality of optical modulators and respectively electrically connected to the plurality of optical modulators.

14. The photonic integrated circuit chip according to claim 6, characterized in that: The second photodetector array includes a plurality of second photodetectors, wherein the plurality of fourth grating couplers are respectively coupled to the plurality of second photodetectors, The number of the plurality of fourth grating couplers is equal to the number of the plurality of second photodetectors.

15. The photonic integrated circuit chip according to claim 14, characterized in that: The optical modulator array further comprises a plurality of second directional couplers, the plurality of second directional couplers are arranged beside the fourth side, wherein each second directional coupler is correspondingly arranged beside one of the plurality of second light detectors, one end of each second directional coupler is coupled to the optical modulator array, and the other end and the further end of each second directional coupler are respectively coupled to the corresponding second light detector and the plurality of fourth grating couplers, The plurality of second directional couplers are used to split the third light beam from the light modulator array into the fourth light beam and the fifth light beam.

16. The photonic integrated circuit chip according to claim 15, characterized in that: The plurality of pads include a plurality of fifth pads and a third ground pad, the plurality of fifth pads and the third ground pad are arranged beside the second photodetector array, the plurality of fifth pads are electrically connected to the plurality of second photodetectors respectively, and the third ground pad is electrically connected to the plurality of second photodetectors, wherein the number of the plurality of fifth bonding pads is equal to the number of the plurality of second light detectors, The plurality of fifth pads and the third ground pad are suitable for being electrically connected to a controller so that the controller can obtain the light intensity of the fourth light beam.

17. The photonic integrated circuit chip according to claim 16, characterized in that: The controller adjusts the light intensity of the third light beam according to a ratio between the light intensity of the fourth light beam and the light intensity of the first light beam.

18. The photonic integrated circuit chip according to claim 3, characterized in that: It further includes a plurality of first alignment keys, a plurality of second alignment keys, and a plurality of third alignment keys, which are arranged beside the first side of the blank area. wherein the plurality of first alignment keys are arranged at one end of the grating coupler array, and the plurality of third alignment keys are arranged at the other end of the grating coupler array relative to the one end, and the plurality of second alignment keys are arranged between the plurality of first alignment keys and the plurality of third alignment keys, and align the first grating coupler, the plurality of second grating couplers, the plurality of third grating couplers, the plurality of fourth grating couplers and the fifth grating coupler respectively. The grating coupler array is suitable for coupling with an optical fiber array. The ratio between the output light beam and the aligned light beam determines the coupling efficiency between the optical fiber array and the grating coupler array.

19. The photonic integrated circuit chip according to claim 1, characterized in that: The photonic integrated circuit chip is suitable for being electrically connected to a circuit board. The photonic integrated circuit chip is electrically connected to the electrical contacts of the circuit board via the plurality of bonding pads to output the electrical signal and receive a driving signal for driving the optical modulator module.

20. A photonic integrated circuit chip, characterized in that: Having a blank area, the photonic integrated circuit chip comprises: a grating coupler array, adapted to receive a light beam from the outside; an optical modulator module coupled to the grating coupler and configured to modulate the light beam from the grating coupler array so that light of a specific wavelength in the light beam is output from the grating coupler array; a plurality of optical waveguides, wherein the optical modulator module is coupled to the grating coupler array via the plurality of optical waveguides; a plurality of heaters electrically connected to the light modulator module; and A plurality of pads electrically connected to the light modulator module and the plurality of heaters, The grating coupler array, the light modulator module, the plurality of optical waveguides, the plurality of heaters and the plurality of pads are arranged around the blank area. The optical modulator module includes a first optical detector array, an optical modulator array and a second optical detector array. The light beam includes a first light beam and a second light beam, the first light beam is transmitted to the first light detector array, and the second light beam is transmitted to the light modulator array, the light modulator array receives and modulates the second light beam to generate a third light beam, the third light beam includes a fourth light beam and a fifth light beam, the fourth light beam is transmitted to the second light detector array, and the fifth light beam is transmitted to the grating coupler array, wherein the plurality of heaters are arranged in the light modulator array, The multiple welding pads are suitable for being electrically connected to a controller so that the controller can obtain the light intensity of the first light beam and the light intensity of the fourth light beam. The controller adjusts the light intensity of the third light beam by regulating the temperature of the light modulator array through the multiple heaters according to the ratio between the light intensity of the fourth light beam and the light intensity of the first light beam.

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