Optical module and optical network device

Abstract

An optical module (10) and an optical network device, which aim to reduce the size of the optical module (10). The optical module (10) comprises a substrate (110), a cover (120), an optical waveguide (130), a laser (140), and a passive device (150). The cover (120) and the substrate (110) jointly form a sealed cavity (101). The optical waveguide (130) is formed on the substrate (110), a first section (131) of the optical waveguide (130) is located in the sealed cavity (101), and a second section (132) is located outside the sealed cavity (101). The laser (140) is located in the sealed cavity (101), and the laser (140) is coupled to the first section (131). The passive device (150) is formed on the substrate (110), and the passive device (150) is coupled to the second section (132). In this way, the sealed cavity (101) can provide a hermetic space for the laser (140), thereby improving the reliability of the laser (140); the optical waveguide (130) and the passive device (150) are integrated on the substrate (110), thereby increasing the functional density of the substrate (110); the laser (140), the optical waveguide (130) and the passive device (150) share the substrate (110), thereby improving the integration level of the optical module (10); in addition, the optical waveguide (130) is arranged on the substrate (110), and thus no additional device for transmitting an optical signal to the laser (140) needs to be provided on the cover (120), thereby avoiding space occupation by the device and reducing the size of the optical module (10).

Description

Optical module and optical network device

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office on March 29, 2024, with application number 202410388653.5 and application name “An optical module and optical network device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of optical devices, and in particular to an optical module and an optical network device. Background Art

[0003] An optical transceiver is an integrated module that converts optical signals into electrical signals and / or electrical signals into optical signals. It plays a vital role in fiber-optic communications and is a key component in optical network equipment. The size of an optical transceiver affects the overall size of the optical network equipment. Summary of the Invention

[0004] The embodiments of the present application provide an optical module and an optical network device, aiming to reduce the volume of the optical module.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions.

[0006] In a first aspect, embodiments of the present application provide an optical module. The optical module includes a substrate, a cover, an optical waveguide, a laser, and passive components. The cover and the substrate together form a sealed cavity; the optical waveguide is formed on the substrate, and the optical waveguide has a first section and a second section that are interconnected, the first section being located within the sealed cavity, and the second section being located outside the sealed cavity. The laser is located within the sealed cavity and coupled to the first section. The passive components are formed on the substrate and coupled to the second section. Thus, the sealed cavity provides an airtight space for the laser, placing the laser in a stable stress and atmosphere environment, thereby increasing the reliability of the laser. The optical waveguide and passive components can be integrated on the substrate, eliminating the need for the optical waveguide and substrate to be separately arranged and then interconnected, and the need for the passive components and substrate to be separately arranged and then interconnected. This increases the substrate's base material density. The laser, optical waveguide, and passive components share a common substrate, improving the integration density of the optical module. In addition, the optical waveguide is provided on the substrate, and there is no need to provide a device for transmitting optical signals as a laser on the cover, thereby avoiding the device from occupying space and reducing the volume of the optical module.

[0007] In conjunction with the first aspect, in some achievable embodiments, the optical module further includes a power amplifier located within the sealed cavity and coupled to the second segment. Consequently, the power amplifier and the laser are both located within the same sealed cavity, which provides a stable and sealed environment for the power amplifier and the optical waveguide. This improves the reliability of the power amplifier and the optical waveguide. Furthermore, the power amplifier and the optical waveguide share a common substrate, thereby increasing the integration density of the optical module.

[0008] In conjunction with the first aspect, in some achievable embodiments, the optical module further includes: a semiconductor cooler, the semiconductor cooler being located outside the sealed cavity, the semiconductor cooler including an electrical connection line, a heating end, and a cooling end, the cooling end being connected to the cover, the cooling end being closer to the laser than the heating end; one end of the electrical connection line being electrically connected to the cooling end, and the other end being electrically connected to the substrate. Thus, because the cooling end of the semiconductor cooler, which is closer to the laser, is closer to the substrate, the electrical connection line is electrically connected to the substrate and the cooling end. The shorter length of the electrical connection line helps reduce the space occupied by the semiconductor cooler. Furthermore, compared to electrically connecting the electrical connection line to the heating end, electrically connecting the electrical connection line to the cooling end reduces the distance between the electrical connection line and the substrate, making the semiconductor cooler more compact.

[0009] In conjunction with the first aspect, in some achievable embodiments, the passive component is formed by photolithography. Thus, the passive component is in direct contact with the substrate, eliminating the need for an additional carrier board, thereby increasing the integration of the passive component and the substrate and facilitating miniaturization of the optical module.

[0010] In conjunction with the first aspect, in some achievable embodiments, the optical module further includes a lens; and coupling the laser to the first segment includes coupling the laser to the first segment via the lens. In this manner, the lens can achieve mode field conversion, coupling the laser's output beam into the optical waveguide. The laser and the first segment of the optical waveguide are coupled via free space.

[0011] In conjunction with the first aspect, in some achievable embodiments, the optical module further includes: a photonic bonding wire; and coupling the laser to the first segment includes coupling the laser to the first segment via the bonding wire. In this way, the light beam emitted by the laser can also be coupled to the first segment of the optical waveguide.

[0012] In combination with the first aspect, in some achievable embodiments, the optical module further includes: optical glue, and coupling the laser with the first segment includes: coupling the laser with the first segment via optical glue.

[0013] In conjunction with the first aspect, in some possible implementations, the optical module further includes: a housing and an optical signal processor; the substrate, the cover, and the optical signal processor are all located within the housing, and the optical signal processor is coupled to the second segment. In this manner, the optical signal processor interconnects optical signals via optical waveguides and lasers. Because the optical waveguides and passive components are integrated on the substrate, the overall housing is smaller, thereby reducing the size of the optical module.

[0014] In conjunction with the first aspect, in some achievable embodiments, the optical module further includes a heat-conducting layer located within the sealed cavity and between the cover and the laser. Thus, the heat-conducting layer can transfer heat from the laser to the cover, thereby improving heat dissipation of the laser.

[0015] In combination with the first aspect, in some achievable embodiments, the material of the cover includes at least one of silicon or ceramic.

[0016] In a second aspect, embodiments of the present application provide an optical module. The optical module includes a substrate, a cover, an optical waveguide, an optical amplifier, and passive components. The cover and the substrate together form a sealed cavity; the optical waveguide is formed on the substrate, comprising a first segment and a second segment connected to each other, the first segment being located within the sealed cavity and the second segment being located outside the sealed cavity; the optical amplifier is located within the sealed cavity and coupled to the first segment; and the passive components are formed on the substrate and coupled to the second segment. Thus, the sealed cavity provides an airtight space for the optical amplifier, maintaining a stable stress and atmosphere environment and increasing its reliability. The optical waveguide and passive components can be integrated on the substrate, eliminating the need for the optical waveguide and substrate to be separately arranged and then connected to each other, and the need for the passive components and substrate to be separately arranged and then connected to each other. This increases the substrate's base material density. The optical amplifier, optical waveguide, and passive components share a common substrate, improving the integration density of the optical module. In addition, the optical waveguide is arranged on the substrate, and there is no need to arrange a device for transmitting optical signals as an optical amplifier on the cover, thereby avoiding the device taking up space and reducing the volume of the optical module.

[0017] In a third aspect, embodiments of the present application provide an optical network device. The optical network device includes a communication port and any one of the optical modules provided in the first or second aspects. The communication port is used to transmit optical signals from the optical network device to other network devices via the optical module, and / or to receive optical signals transmitted by other network devices. Since the volume of the optical module is reduced, the volume of the components including the optical module is also reduced accordingly, effectively improving the integration of the optical network device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of an optical network terminal.

[0019] FIG2 is a schematic structural diagram of an optical module provided in an embodiment of the present application.

[0020] FIG3 is a schematic structural diagram of a substrate provided in an embodiment of the present application.

[0021] FIG4 a is a diagram showing a connection method between a laser and an optical waveguide provided in an embodiment of the present application.

[0022] FIG4 b is a diagram showing another connection method between a laser and an optical waveguide provided in an embodiment of the present application.

[0023] FIG4 c is a diagram showing another connection method between a laser and an optical waveguide provided in an embodiment of the present application.

[0024] FIG5 a is a schematic structural diagram of a substrate including multiple lasers provided in an embodiment of the present application.

[0025] FIG5 b is a schematic structural diagram of an optical module of a laser with multiple optical ports provided in an embodiment of the present application.

[0026] FIG6 is a schematic structural diagram of a semiconductor cooler provided in an embodiment of the present application.

[0027] FIG7 is a schematic structural diagram of a semiconductor cooler and a cover body provided in an embodiment of the present application.

[0028] FIG8 a is a schematic diagram of the optical path of a directly modulated optical module provided in an embodiment of the present application.

[0029] FIG8 b is a schematic diagram of the optical path of a coherent optical module provided in an embodiment of the present application.

[0030] FIG9 a is a schematic structural diagram of another optical module provided in an embodiment of the present application.

[0031] FIG9 b is a schematic structural diagram of another optical module provided in an embodiment of the present application.

[0032] FIG10 is a flow chart of a process for preparing an optical module provided in an embodiment of the present application.

[0033] FIG11 is a schematic structural diagram of another optical module provided in an embodiment of the present application.

[0034] FIG12 is a schematic diagram of the optical path of another optical module provided in an embodiment of the present application.

[0035] FIG13 is a flow chart of a process for preparing an optical module according to an embodiment of the present application.

[0036] In the figure: 10-optical module; 110-substrate; 120-cover; 130-optical waveguide; 131-first section; 132-second section; 140-laser; 150-passive components; 101-sealed cavity; 102-connection layer; 103-heat conductive layer; 104-wire; 105-conductive via; 106-solder ball; 160-semiconductor refrigerator; 107-lens; 108-photonic bonding plate; 109-optical adhesive; 170-power amplifier; 161-heating end; 162-cooling end; 163-electrical connecting wire; 30-housing; 31-connector; 32-first optical port; 33-second optical port; 200-optical module; 210-substrate; 230-optical amplifier; 210-substrate; 1021-first chip metal layer; 1022-second chip metal layer; 1023-solder layer. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of this application clearer, this application will be further described in detail below with reference to the accompanying drawings.

[0038] Hereinafter, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified with "first," "second," etc., may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0039] In addition, in this application, directional terms such as "upper" and "lower" are defined relative to the orientation of the components in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, and they can change accordingly according to changes in the orientation of the components in the drawings.

[0040] Passive Optical Network (PON): A passive optical network (PON) is an optical distribution network (ODN) without any active electronic devices between the optical line termination (OLT) and the optical network unit (ONU).

[0041] Optical distribution network (ODN): An ODN is a fiber-to-the-home (FTTH) cable network based on PON equipment. Its function is to provide an optical transmission channel between the OLT and the ONU.

[0042] Figure 1 is a schematic diagram of the structure of an optical network terminal. Referring to Figure 1, the optical network terminal includes an optical network terminal (OLT), an optical distribution network (ODN), and an optical network unit (ONU). The ODN includes optical fibers and optical splitters. The optical splitter does not modify the information carried by the light.

[0043] Taking the optical network terminal (OLT) as an example, the OLT includes at least one optical network device, which includes an optical module 10 and a communication port. The communication port transmits optical signals from the optical network device to other network devices via the optical module 10, and / or receives optical signals from other network devices. A passive optical network (PON) transmits optical signals from the PON to an optical transmission network (OTN) via the optical module 10, or receives optical signals from the PON via the optical module 10. The same applies to other optical network devices.

[0044] An optical module, also known as an optical transmission module, is used for transmitting optical signals. The optical modules provided in the embodiments of the present application can be applied to Passive Optical Networks (PON), Gigabit Passive Optical Networks (GPON), 10-Gigabit Passive Optical Networks (XGS-PON), or 50 Gigabit Passive Optical Networks (50GPON), etc.

[0045] Figure 2 is a schematic diagram of the structure of an optical module 10 provided in an embodiment of the present application. Referring to Figure 2 , optical module 10 includes a substrate 110, a cover 120, an optical waveguide 130, a laser 140, and passive components 150. The cover 120 and substrate 110 together form a sealed cavity 101. The laser 140 is located within the sealed cavity 101 and is connected to the substrate 110.

[0046] An optical waveguide 130 is formed on a substrate 110 and includes a first section 131 and a second section 132 connected to each other. The first section 131 is located within the sealed cavity 101, and the second section 132 is located outside the sealed cavity 101. A laser 140 is coupled to the first section 131. A passive device 150 is formed on the substrate 110 and coupled to the second section 132.

[0047] Thus, the sealed cavity 101 can provide a space with good airtightness for the laser 140, so that the laser 140 is in a stable stress and atmosphere environment, thereby increasing the reliability of the laser 140. The optical waveguide 130 and the passive device 150 can be integrated on the substrate 110. The optical waveguide 130 and the substrate 110 do not need to be independently set up and then connected to each other, and the passive device 150 and the substrate 110 do not need to be independently set up and then connected to each other. The base material density of the substrate 110 is increased. The laser 140, the optical waveguide 130 and the passive device 150 share the substrate 110, thereby improving the integration of the optical module 10. In addition, the optical waveguide 130 is set on the substrate 110, and there is no need to set up a device on the cover 120 for transmitting optical signals for the laser 140, thereby avoiding the device taking up space and reducing the volume of the optical module 100.

[0048] The optical module 10 provided in the embodiment of the present application overcomes the problem that the passive device 150 and the laser 140 cannot share a substrate, increases the integration of the optical module 10, and is conducive to the miniaturization of the optical module 10.

[0049] In the embodiments of the present application, coupling can be understood as direct coupling and / or indirect coupling, and "coupling connection" can be understood as direct coupling connection and / or indirect coupling connection. Direct coupling can also be referred to as "optical signal connection", which is understood as the physical contact between components and the conduction of optical signals. It can also be understood as a form of connection between different components through physical lines or devices such as prisms and optical waveguides that can transmit optical signals; "indirect coupling" can be understood as the conduction of electrical signals between two optical devices through an air-space / non-contact method.

[0050] The present application embodiment does not limit the material of the cover 120. In some embodiments, the material of the cover 120 includes silicon,

[0051] Figure 3 is a schematic diagram of the structure of substrate 110 provided in an embodiment of the present application. Referring to Figure 3 , passive components 150 and optical waveguide 130 are provided on substrate 110. This embodiment of the present application does not restrict the path along which optical waveguide 130 extends on substrate 110. For example, the path along which optical waveguide 130 extends can be a straight line, a curved line, or a broken line. The path is configured based on the distribution of components on substrate 110.

[0052] In some embodiments of the present application, the substrate 110 is made of silicon. The substrate 110 and components such as the optical waveguide 130 and passive components 150 formed on the substrate 110 can be considered a silicon optical chip. In some embodiments, an optical transceiver component may also be provided on the silicon optical chip. Forming the optical waveguide 130 and passive components 150 on a silicon wafer allows the optical waveguide 130, passive components 150, and laser 140 to share the same substrate 110. This can increase the integration of the substrate 110.

[0053] In some embodiments of the present application, the substrate 110 is an integrally formed component. Thus, the optical waveguide 130 and the passive components 150 are formed on the integrally formed substrate 110, eliminating the need for an additional carrier board for supporting the optical waveguide 130 and the passive components 150. This increases the integration of the optical module 10 and reduces the size of the optical module 10.

[0054] The "passive" in passive devices refers to components that can display their characteristics without the need for an external power supply.

[0055] The embodiment of the present application does not limit the type of the passive component 150 , and the passive component 150 may be configured according to the function of the optical module 10 .

[0056] For example, in some embodiments, the passive device 150 is formed by photolithography. In other words, the passive device 150 is formed by photolithography of the substrate 110. This allows the passive device 150 to directly contact the substrate 110, eliminating the need for an additional carrier. This increases the integration of the passive device 150 and the substrate 110, facilitating miniaturization of the optical module.

[0057] As shown in Figure 3, in some embodiments, a connection layer 102 is provided on the surface of the substrate 110, and the connection layer 102 is connected to the cover 120 (as shown in Figure 2). The connection layer 102 ensures that the connection between the substrate 110 and the cover 120 has excellent airtightness.

[0058] Exemplarily, the connection layer 102 may include an under-bump metallization (UBM), which may improve the airtightness of the sealed cavity 101. Exemplarily, in some embodiments, the connection layer 102 includes a solder layer and two chip metal layers, with the solder layer located between the two chip metal layers. For example, the connection layer 102 includes a first chip metal layer 1021, a second chip metal layer 1022, and a solder layer 1023. The solder layer 1023 is located between the first chip metal layer 1021 and the second chip metal layer 1022. The first chip metal layer 1021 and the second chip metal layer 1022 may improve the wettability of the solder in the solder layer, thereby improving the airtightness of the sealed cavity 101.

[0059] It is understandable that the connection layer 102 may also be other structures. In some embodiments, the connection layer 102 may be a solder layer. For example, the cover 120 and the substrate 110 are connected by reflow soldering or eutectic soldering and a solder layer is formed at the connection between the cover 120 and the substrate 110. In some embodiments, the connection layer 102 may be formed by a laser welding process. For example, by laser heating the connection between the cover 120 and the substrate 110, the contact area between the two is remelted by instantaneous high temperature, and the connection layer 102 is formed at the connection between the substrate 110 and the cover 120, completing the assembly of the substrate 110 and the cover 120 to form the sealed cavity 101.

[0060] In some embodiments of the present application, the connecting layer 102 may also be an adhesive layer. In other words, the substrate 110 and the cover 120 may be connected via the adhesive layer. This simplifies the connection process between the substrate 110 and the cover 120 and reduces the connection cost.

[0061] Returning to FIG. 2 , in some embodiments of the present application, the substrate 110 is further provided with a wire 104 , which is used to transmit electrical signals. For example, the wire 104 is electrically connected to the laser 140 , and the wire 104 can provide the laser 140 with an electrical signal.

[0062] For example, the conductors can be formed on the substrate 110 using a wiring process. In some embodiments, the conductors 104 can be multi-layered wiring. Multi-layered wiring can form a larger wiring space on the substrate 110, providing a more complex circuit for the optical module 10.

[0063] The embodiment of the present application does not limit the material of the wire 104 . For example, the material of the wire 104 may include at least one of copper and its alloys or aluminum and its alloys.

[0064] The embodiment of the present application does not limit the extension path of the wire 104 , and the wire 104 may be arranged according to the placement relationship of the components on the substrate 110 that need to transmit electrical signals.

[0065] In some embodiments of the present application, the optical module 10 may further include an electrical chip 40 , which is connected to the substrate 110 . For example, the wire 104 of the electrical chip 40 is connected to the laser 140 .

[0066] In some embodiments of the present application, substrate 110 is further provided with conductive vias 105 and solder pads 106. Solder pads 106 are located outside sealed cavity 101. Conductive wires 104 are connected to solder pads 106 through conductive vias 105. Solder pads 106 can be electrically connected to the printed circuit board of optical module 10. In this way, conductive wires 104, conductive vias 105, and solder pads 106 can fan out the electrical signals from laser 140.

[0067] The embodiment of the present application does not limit the number of wires 104 , conductive vias 105 , and solder balls 106 , and they can be set according to the number of electrical interfaces of the laser 140 and the circuit design.

[0068] In some embodiments of the present application, the optical module 10 may further include a heat-conducting layer 103, which is located within the sealed cavity 101. The laser 140 and the cover 120 are connected via the heat-conducting layer 103. The heat-conducting layer 103 can transfer heat from the laser 140 to the cover 120, thereby improving the heat dissipation effect of the laser 140.

[0069] In some embodiments of the present application, the material of the thermally conductive layer 103 may be, for example, a thermal interface material (TIM). For example, the TIM may be a thermally conductive gel. The thermally conductive gel is flexible and can conform well to the laser 140 and the cover 120. Even if there is an assembly error between the laser 140 and the cover 120, the flexible thermally conductive gel can eliminate the error, allowing the heat from the laser 140 to be effectively transferred to the thermally conductive gel and the cover 120.

[0070] In some embodiments, the heat dissipation surface of the laser 140 is in contact with the heat conducting layer 103 , and the heat conducting layer 103 can transfer the heat of the heat dissipation surface to the cover 120 , thereby improving the heat dissipation performance of the laser 140 .

[0071] The present application does not limit the material of the cover 120. In some embodiments, the cover 120 is made of silicon. The cover 120 made of silicon is smaller in size. In some embodiments, the cover 120 is made of ceramic or metal.

[0072] The embodiment of the present application does not limit the connection method between the laser 140 and the substrate 110. For example, the laser 140 is mounted on the substrate 110 by flip chip mounting, and the flip chip mounting method is used to achieve electrical connection between the wire 104 and the laser 140.

[0073] The embodiment of the present application does not limit the coupling method between the laser 140 and the first section 131 of the optical waveguide 130 , and can be set according to the type of the light outlet of the laser 140 .

[0074] In the example of FIG2 , the light output port of laser 140 is a hybrid integrated optical port, and laser 140 and first section 131 of optical waveguide 130 are coupled via butt coupling. In the example of FIG2 , laser 140 has an end-face coupled optical port, and optical waveguide 130 has an end-face coupled optical port. The end-face coupled optical port of laser 140 is coupled to the end-face coupled optical port of optical waveguide 130.

[0075] Figure 4a illustrates a connection method for a laser 140 and an optical waveguide 130 according to an embodiment of the present application. Referring to Figure 4a, the optical module 10 further includes a lens 107, through which the laser 140 and the first segment 131 of the optical waveguide 130 are coupled. This enables mode-field conversion, coupling the light beam emitted by the laser 140 into the optical waveguide 130. The laser 140 and the first segment 131 of the optical waveguide 130 are coupled via free space.

[0076] 4a, a groove is provided on the substrate 110, and the laser 140 is located in the groove, and the laser 140 is connected to the substrate 110 via an adhesive layer 141. For example, the adhesive layer 141 may be made of conductive adhesive such as silver adhesive or copper adhesive.

[0077] FIG4 b illustrates another embodiment of the present application, providing a connection diagram of a laser 140 and an optical waveguide 130. Referring to FIG4 b , the optical module 10 further includes a photonic wire bonding (PWB) 108 , through which the laser 140 and the first segment 131 of the optical waveguide 130 are coupled. In the example of FIG4 b , the end-face coupling optical port of the laser 140 and the end-face coupling optical port of the optical waveguide 130 are coupled via the photonic wire bonding 108 . In this manner, the light beam emitted by the laser 140 can also be coupled to the first segment 131 of the optical waveguide 130 .

[0078] FIG4 c is another diagram illustrating another connection method between the laser 140 and the optical waveguide 130 provided in an embodiment of the present application. Referring to FIG4 b , the optical module 10 further includes an optical adhesive 109 , which can be formed on the substrate 110 using micro-transfer printing (TP) technology. The laser 140 and the first section 131 of the optical waveguide 130 are coupled via the optical adhesive 109 . In this manner, the light beam emitted by the laser 140 can also be coupled to the optical waveguide 130 . In the example of FIG4 c , the end-face coupling optical port of the laser 140 and the end-face coupling optical port of the optical waveguide 130 are coupled via the optical adhesive 109 .

[0079] In some embodiments of the present application, the end-face coupling port of the laser 140 and the end-face coupling port of the optical waveguide 130 are coupled via a heterogeneous integration (dai to wafer bonding) process, so that the light beam emitted by the laser 140 can also be coupled to the optical waveguide 130 .

[0080] The embodiments of the present application do not limit the number of lasers 140 . In some embodiments of the present application, there are multiple lasers 140 .

[0081] In some embodiments of the present application, the optical module may further include components such as a modulator and a driver.

[0082] Figure 5a is a schematic structural diagram of a substrate 110 including a plurality of lasers 140 provided in an embodiment of the present application. Referring to Figure 5a, four lasers 140 are provided on the substrate 110. The four lasers 140 are all located in a sealed cavity 101. One sealed cavity 101 can provide a stable and closed environment for the four lasers 140 at the same time. The four lasers 140 are arranged at intervals to avoid heat concentration of the lasers 140. The connection method of each laser 140 and the optical waveguide 130 is described in the aforementioned Figures 2, 4a, 4b and 4c. The optical module including the substrate 110 shown in Figure 5a is a four-channel optical module. They are sig-Out1, sig-Out2, sig-Out3, and sig-Out4 respectively.

[0083] In Figure 5a, MZ stands for Mach-Zehnder modulator, which splits the input light into two equal signals, each entering the modulator's two optical branches. DRV stands for driver. Driver DRV is used to drive the Mach-Zehnder modulator.

[0084] It is understandable that in other embodiments, the number of lasers 140 in the sealed cavity 101 may be other, for example, one, two, three, five or more, etc. The number may be set according to the optical channels required by the optical module.

[0085] In the embodiment of the present application, the multi-channel optical module may not be provided with multiple lasers 140. For example, a laser 140 with multiple optical ports may be used.

[0086] Figure 5b is a schematic diagram of the structure of an optical module 10 with multiple optical ports and a laser 140, according to an embodiment of the present application. Referring to Figure 5b, the difference between Figure 5b and Figure 5a is that the laser 140 has four optical ports. Each optical port is coupled to an optical waveguide 130. Thus, the optical module 10 has four optical channels. The number of lasers 140 within the sealed cavity 101 is one, and the volume of the sealed cavity 101 is relatively small, which can reduce the size of the optical module 10.

[0087] In some embodiments of the present application, the type of laser 140 can be a laser diode (LD) chip, a distributed feedback laser (DFLD), etc. This embodiment of the present application does not limit this. In some embodiments of the present application, the aforementioned laser 140 can also be a thin-film lithium niobate modulator.

[0088] Returning to FIG. 4 c , in some embodiments of the present application, the optical module 100 further includes a thermoelectric cooler (TEC) 160 . The TEC 160 is located outside the sealed cavity 101 and is connected to the cover 120 .

[0089] FIG6 is a schematic diagram of the structure of a semiconductor cooler 160 provided in an embodiment of the present application. Referring to FIG6 , semiconductor cooler 160 includes a heating end 161, a cooling end 162, and an electrical connection line 163. When semiconductor cooler 160 is in operation, the temperature of heating end 161 is higher than the temperature of cooling end 162.

[0090] In FIG6 , the semiconductor cooler 160 includes an N (negative) type semiconductor and a P (positive) type semiconductor. The N-type semiconductor and the P-type semiconductor are electrically connected. The N-type semiconductor is also called an electron-type semiconductor. An N-type semiconductor is an impurity semiconductor in which the concentration of free electrons is much greater than the concentration of holes. The P-type semiconductor is also called a hole-type semiconductor. A P-type semiconductor is an impurity semiconductor in which the concentration of holes is much greater than the concentration of free electrons. The heating end 161 and the cooling end 162 can be adjusted by adjusting the properties of the electrodes electrically connected to the N-type semiconductor. For example, in FIG6 , the N-type semiconductor is electrically connected to the positive pole of the power supply, and the P-type semiconductor is electrically connected to the negative pole of the power supply. In FIG6 , the electrical connection line 163 is electrically connected to the cooling end 162.

[0091] Figure 7 is a schematic diagram of the structure of a semiconductor cooler 160 and cover 120 provided in an embodiment of the present application. Referring to Figure 7 , the cooling end 162 is closer to the laser 140 than the heating end 161. Electrical connection wire 163 is electrically connected to the substrate 110. Because the cooling end 162 of the semiconductor cooler 160, which is closer to the laser 140, is closer to the substrate 110, the electrical connection wire 163 electrically connects the substrate 110 and the cooling end 162. The shorter length of electrical connection wire 163 helps reduce the space occupied by the semiconductor cooler 160.

[0092] In addition, compared with the electrical connection line 163 being electrically connected to the heating end 161 , the electrical connection line 163 is electrically connected to the cooling end 162 , so that the distance between the electrical connection line 163 and the substrate 110 is smaller, making the semiconductor cooler 160 more compact.

[0093] In some embodiments of the present application, one end of the electrical connection line 163 is electrically connected to the heating terminal 161, and the other end of the electrical connection line 163 is electrically connected to the substrate 110. For example, the other end of the electrical connection line 163 is electrically connected to the solder ball 106 on the substrate 110.

[0094] The present embodiment does not limit the type of passive component 150. For example, the passive component 150 may be a receiver optical sub-assembly (ROSA), a transmitter optical sub-assembly (TSOA), an optical modulator, or a variable optical attenuator (VOA). The passive component 150 is configured based on the structure and usage scenario of the optical module 10.

[0095] The embodiment of the present application does not limit the type of the optical module 10. In some embodiments, the optical module 10 can be a direct-modulation optical module. In some embodiments, the optical module 10 can be a coherent optical module.

[0096] In some embodiments of the present application, the optical module 10 may further include an optical digital signal processor (ODSP).

[0097] FIG8a is a schematic diagram of the optical path of a direct-modulation optical module provided in an embodiment of the present application. Referring to FIG8a, the direct-modulation optical module includes an optical digital signal processor oDSP, an optical receiving module, an optical modulator, and a laser.

[0098] For example, light emitted by laser 140 enters the optical modulator through optical waveguide 130. The digital-to-analog conversion (DAC) of the optical digital signal processor (oDSP) transmits the electrical signal to the modulator. After modulation, the electrical signal from the oDSP is converted into an optical signal and then transmitted, achieving signal modulation. Similarly, the modulated light received by the optical receiving module is converted into an electrical signal by the receiver. The electrical signal enters the analog-to-digital converter (ADC) of the optical digital signal processor (oDSP) for signal demodulation.

[0099] In Figure 8a, the optical modulator can be the Mach-Zehnder modulator described above. The bi-directional optical sub-assembly (BOSA) primarily comprises a transmitting optical sub-assembly (TOSA) and a receiving optical sub-assembly (ROSA). The TOSA converts electrical signals into optical signals and transmits them through an optical fiber. The ROSA receives optical signals from the optical fiber and converts them into electrical signals.

[0100] In order to improve the integration level and reduce the volume of the directly modulated optical module, the optical receiving module, the optical modulator and the laser are all integrated on the substrate 110 .

[0101] Figure 8b is a schematic diagram of the optical path of a coherent optical module provided in an embodiment of the present application. Referring to Figure 8b , the coherent optical module includes an optical signal processor (oDSP), a laser 140, an optical receiver module, an optical modulator, and a power amplifier (booster-amplifier, BA). Laser 140, the optical receiver module, the optical modulator, and the power amplifier are all integrated on substrate 110, simplifying the packaging of laser 140 while also facilitating the miniaturization of the coherent optical module.

[0102] Exemplarily, the power amplifier BA may be an erbium doped fiber amplifier (EDFA) or a semiconductor optical amplifier (SOA).

[0103] In the example of Figure 8b, light emitted by one laser 140 enters an optical modulator. The modulator's digital-to-analog converter transmits the electrical signal to the modulator, which then modulates the oDSP's electrical signal into an optical signal. This optical signal is amplified once by a power amplifier BA, achieving signal modulation. Light emitted by another laser 140 enters an optical receiver module. The modulated light and intrinsic light received by the optical receiver module are then converted into an electrical signal by interference between the signal light and the intrinsic light in the receiver. This electrical signal then enters the oDSP's analog-to-digital converter for signal demodulation.

[0104] In some embodiments, there may be only one laser 140 . The light emitted by the laser 140 is split by a polarization beam splitter (PBS). One beam of light enters the optical modulator, and the other beam of light enters the optical receiving module.

[0105] In some embodiments of the present application, the optical module 10 may further include a housing 30. The substrate 110, cover 120, laser 140, and optical waveguide 130 are all located within the housing 30. The optical signal processor 20 is located within the housing 30, and the optical signal processor 20 and the laser 140 are optically interconnected. Exemplarily, the optical signal processor 20 and the laser 140 are optically interconnected via the optical waveguide 130.

[0106] In some embodiments, the optical module 10 is further provided with a connector 31 , which is provided on the housing 30 , and the optical signal of the optical signal processor 20 is output through the connector 31 . Alternatively, the signal is input into the optical signal processor 20 through the connector 31 .

[0107] Exemplarily, the optical module 10 is further provided with a first optical port 32 and a second optical port 33 , both of which are provided on the housing 30 , and the optical signal is input into the optical module 10 from the second optical port 33 , and the optical signal is output from the optical module 10 from the first optical port 32 .

[0108] In some embodiments of the present application, the coherent optical module has various structural forms, which are described below with reference to FIG. 9 a and FIG. 9 b as examples.

[0109] In some embodiments of the present application, the optical module 10 further includes a power amplifier (booster-amplifier, BA) 170 (as shown in FIG9 a ), which is disposed on the substrate 110. In some embodiments, the power amplifier 170 and the laser 140 are both located within the sealed cavity 101. In some embodiments, the power amplifier 170 and the laser 140 are independently sealed and disposed in different sealed cavities.

[0110] FIG9 a is a schematic diagram of the structure of another optical module 10 provided in an embodiment of the present application. Referring to FIG9 a , the optical module 10 includes a laser 140, a power amplifier 170, a Y-channel mixer (Hybrid Mixer-Y), an X-channel mixer (Hybrid Mixer-X), a Y-channel Mach-Zehnder modulator (MZ-Y), an X-channel Mach-Zehnder modulator (MZ-X), a polarization splitter and rotator (PSR), a beam splitter (BS), a variable optical attenuator (VOA), a wavelength locker (WVL), and a photodiode (PD).

[0111] In the example of Figure 9a, power amplifier 170 and laser 140 are located in separate sealed cavities. For example, in Figure 9a, laser 140 is located in sealed cavity 101a. Power amplifier 170 is located in sealed cavity 101b. Separately packaging power amplifier 170 and laser 140 prevents heat concentration in power amplifier 170 and laser 140.

[0112] 9a, the wavelength splitter BS, variable optical attenuator VOA, wavelength meter WVL, and photodiode PD are all passive components 150. The wavelength splitter BS, variable optical attenuator VOA, wavelength meter WVL, and photodiode PD are all integrated on the substrate 110, effectively improving the integration of the optical module 10.

[0113] In some embodiments of the present application, the power amplifier 170 may also be disposed in the sealed cavity 101 .

[0114] Figure 9b is a schematic diagram of the structure of another optical module 10 provided in an embodiment of the present application. Figure 9b differs from Figure 9a in that power amplifier 170 is also located within sealed cavity 101 and is coupled to first section 131 of optical waveguide 130. For the remaining structures in Figure 9b, please refer to the description of Figure 9a. These details will not be repeated here.

[0115] The power amplifier 170 and the laser 140 are both located within the same sealed cavity 101, which provides a stable and enclosed environment for the power amplifier 170 and the optical waveguide 130. This improves the reliability of the power amplifier 170 and the optical waveguide 130. Furthermore, the power amplifier 170 and the optical waveguide 130 share the substrate 110, thereby increasing the integration level of the optical module 10.

[0116] The present embodiment does not limit the preparation process of the optical module 10. FIG10 is a flow chart of a preparation process of the optical module 10 provided in the embodiment of the present application. Referring to FIG10 , the preparation process of the optical module 10 includes:

[0117] S1. Prepare the cover 120.

[0118] There are various ways to prepare the cover 120. In some embodiments, preparing the cover 120 includes S11. etching a first raw material to form the shape of the cover 120. S12. forming an UBM on the surface of the first raw material. S13. pre-forming solder on the UBM layer. S14. cutting to form the cover 120.

[0119] S2. Prepare the substrate 110.

[0120] There are various ways to prepare substrate 110. In some embodiments, preparing substrate 110 includes S21. Etching a second raw material to form a corresponding shape and structures such as optical waveguides and passive components on the second raw material. S22. Forming an UBM on the surface of the second raw material. S23. Pre-forming solder on the UBM layer. S24. Cutting to form substrate 110.

[0121] In the embodiment of the present application, either S23 or S13 can be executed, or both S23 and S13 can be executed.

[0122] S3. Prepare the laser 140.

[0123] In some embodiments, fabricating the laser 140 includes S31. growing an epitaxial wafer on a substrate, S32. performing photolithography, S33. forming a UBM on the substrate, and S34. performing cleavage to form the laser 140.

[0124] Illustratively, cleaving the laser 140 refers to separating the plurality of lasers 140 .

[0125] It is understood that the order of S1, S2 and S3 can be set according to needs. For example, it can be in the order of S1, S2 and S3, or in the order of S3, S1 and S2, or in the order of S3, S2 and S1, etc.

[0126] S4. Connect the laser 140 and the substrate 110.

[0127] Exemplarily, the laser 140 and the substrate 110 are coupled to the optical waveguide on the substrate 110 by adopting an optical-optical hybrid integration method.

[0128] The process of connecting the laser 140 and the substrate 110 includes mechanical connection, electrical signal connection, and optical signal connection between the laser 140 and the substrate 110. For example, the wires on the substrate 110 are connected to the electrical interface of the laser 140. The laser 140 is coupled to the optical waveguide on the substrate.

[0129] The coupling method between the laser 140 and the optical waveguide on the substrate can be found in the description of FIG. 4 a , FIG. 4 b and FIG. 4 c , which will not be described again here.

[0130] S5. Connect the laser 140 and the heat conducting layer 103.

[0131] The heat conducting layer 103 can effectively adjust the installation error during the installation process of the laser 140 .

[0132] S6. Connect the substrate 110 and the cover 120.

[0133] For example, the substrate 110 and the cover 120 are connected by welding.

[0134] S7. Connect the TEC.

[0135] In some embodiments, it may also include testing of sealing performance and testing of devices.

[0136] The process shown in FIG10 can be used to prepare the optical module shown in FIG9a or FIG9b. For example, the optical module shown in FIG9a can be formed by placing the laser 140 in the cover. The optical module shown in FIG9b can be formed by placing the laser 140 and the power amplifier in the cover.

[0137] In some embodiments of the present application, the sealed cavity may not contain a laser, for example, only an optical amplifier.

[0138] Figure 11 is a schematic diagram of the structure of another optical module 200 provided in an embodiment of the present application. Referring to Figure 11 , optical module 200 includes a substrate 210, a cover 120, an optical waveguide 130, an optical amplifier 230, and a passive component 220. The cover 120 and substrate 210 together form a sealed cavity 101. The optical amplifier 230 is located within the sealed cavity 101 and is connected to the substrate 210. Both the passive component 220 and the optical amplifier 230 are connected to the optical waveguide 130. Both the passive component 220 and the optical amplifier 230 are coupled to the optical waveguide 130.

[0139] In FIG11 , the connection relationship among the substrate 210 , the cover 120 , the optical waveguide 130 , the optical amplifier 230 and the passive device 220 can be found in the related description in FIG2 , which will not be repeated here.

[0140] In the example of FIG11 , in embodiments where the gain of optical amplifier 230 is low, optical amplifier 230 has a low temperature requirement, and optical module 200 may not be provided with semiconductor cooler 160. In embodiments where the gain of optical amplifier 230 is high, optical amplifier 230 has a high temperature requirement, and semiconductor cooler 160 may be provided.

[0141] Similar to the aforementioned optical module including a laser, the optical waveguide 130 and passive component 220 can be integrated on the substrate 210. The optical waveguide 130 and substrate 210 do not need to be separately provided, and the passive component 220 and substrate 210 do not need to be separately provided. The sealed cavity 101 provides an airtight space for the optical amplifier 230, which keeps the passive component 220 in a stable stress and atmosphere environment. The passive component 220, optical waveguide 130, and passive component 220 share the substrate 210, thereby improving the integration of the optical module 200. In addition, since the optical waveguide 130 is provided on the substrate 210, there is no need to provide a component on the cover 120 for transmitting the optical signal for the optical amplifier 230, thus avoiding the space occupied by the component and reducing the volume of the optical module 200.

[0142] The embodiment of the present application does not limit the type of the passive component 220 , and can be configured according to the function of the optical module 200 .

[0143] FIG12 is a schematic diagram of the optical path of another optical module 200 provided in an embodiment of the present application. Referring to FIG12 , the passive components 220 may include a wavelength division multiplexing (WDM), an optical amplifier 230, a Mach-Zehnder modulator (MZ), a wavelength splitter (BS), a photodiode (PD), a trans-impedance amplifier (TIA), a driver (DRV), a variable optical attenuator (VOA), an erbium-doped waveguide (EDW), and a laser 140. For example, light emitted from the optical amplifier 230 is modulated by the MZ before entering the WDM. The erbium-doped waveguide (EDW) utilizes the energy level transitions of Er ions to amplify the light emitted from the MZ. To ensure a wide range of output power, the light emitted from the EDW passes through the VOA and the photodiode (PD) in sequence and is emitted from the first optical port 32.

[0144] In the example of FIG. 12 , the wavelength division multiplexer WDM, the photodiode PD, the variable optical attenuator VOA, and the erbium-doped optical waveguide EDW are all passive components 220 , which are integrated on the substrate 110 .

[0145] The electrical signal received by the photodiode PD is amplified by the transimpedance amplifier TIA and then output to the optical digital signal processor oDSP.

[0146] For example, the optical amplifier 230 can be a pump laser. The sealed cavity enclosed by the substrate 210 and the cover 120 provides a stable environment for the optical amplifier 230, effectively reducing the temperature of the pump laser caused by optical port burnout and optical tweezers effect.

[0147] The sealed cavity 101 formed by the cover 120 and the substrate 210 provides a stable stress and atmosphere environment, thereby ensuring the reliability of the optical amplifier 230 .

[0148] The present embodiment of the present application does not limit the manufacturing process of the optical module 200 of FIG11. FIG13 is a flow chart of the manufacturing process of the optical module 200 provided in the embodiment of the present application. Referring to FIG13 and FIG10, the manufacturing process of the optical module 200 differs from the process flow in FIG10 in that:

[0149] S8. Prepare the optical amplifier 230.

[0150] The embodiment of the present application does not limit the process for preparing the optical amplifier 230 .

[0151] The remaining processes in FIG13 are described in conjunction with FIG10 and will not be repeated here. Furthermore, during substrate preparation, the process can be configured based on the components on the substrate. For example, the substrate preparation process can be selected based on the type and distribution of passive components.

[0152] The above is only a specific embodiment of the present application, but the scope of protection of this application is not limited to this. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An optical module, characterized in that: The optical module includes: substrate; a cover body, wherein the cover body and the substrate together form a sealed cavity; an optical waveguide formed on the substrate, the optical waveguide having a first section and a second section connected to each other, the first section being located within the sealed cavity, and the second section being located outside the sealed cavity; A laser is located in the sealed cavity and coupled to the first segment; and a passive device is formed on the substrate and coupled to the second segment.

2. The optical module according to claim 1, wherein The optical module further includes a power amplifier, which is located in the sealed cavity and is coupled to the second section.

3. The optical module according to claim 1 or 2, characterized in that: The optical module also includes: a semiconductor cooler, which is located outside the sealed cavity, and includes an electrical connection line, a heating end and a cooling end, the cooling end is connected to the cover body, and the cooling end is closer to the laser than the heating end; one end of the electrical connection line is electrically connected to the cooling end, and the other end is electrically connected to the substrate.

4. The optical module according to any one of claims 1 to 3, characterized in that: The passive components are formed by photolithography.

5. The optical module according to any one of claims 1 to 4, characterized in that: The optical module further includes: a lens; The coupling of the laser and the first segment includes: coupling the laser and the first segment through the lens.

6. The optical module according to claim 1, wherein: The optical module further includes: optical glue; The coupling of the laser and the first segment includes: coupling the laser and the first segment through the optical glue.

7. The optical module according to any one of claims 1 to 4, characterized in that: The optical module further includes: a photon bonding wire, The coupling of the laser to the first segment includes: coupling the laser to the first segment via the photonic bonding wire.

8. The optical module according to any one of claims 1 to 7, characterized in that: The optical module further includes: a housing and an optical signal processor; the substrate, the cover and the optical signal processor are all located in the housing, and the optical signal processor is coupled to the second segment.

9. The optical module according to any one of claims 1 to 8, characterized in that: The optical module further includes a heat-conducting layer, wherein the heat-conducting layer is located in the sealed cavity and between the cover and the laser.

10. The optical module according to any one of claims 1 to 9, characterized in that: The cover is made of at least one of silicon, ceramics or metal.

11. The optical module according to any one of claims 1 to 10, characterized in that: The optical module also includes: a connecting layer, the cover body and the substrate are connected through the connecting layer, the connecting layer includes a first chip metal layer, a solder layer and a second chip metal layer stacked in sequence; the cover body is connected to the first chip metal layer, and the substrate is connected to the second chip metal layer.

12. An optical module, characterized in that: The optical module includes: substrate; a cover body, wherein the cover body and the substrate together form a sealed cavity; an optical waveguide formed on the substrate, the optical waveguide having a first section and a second section connected to each other, the first section being located within the sealed cavity, and the second section being located outside the sealed cavity; a power amplifier located in the sealed cavity, wherein the power amplifier is coupled to the first segment; and A passive component is formed on the substrate and is coupled to the second segment.

13. An optical network device, characterized in that: The optical network device comprises a communication port and the optical module according to any one of claims 1 to 12, wherein the communication port is used to send optical signals of the optical network device to other network devices through the optical module, and / or receive optical signals sent by other network devices.

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