A top-in light temperature control silicon light package system with spectral reference locking function

Abstract

The application discloses a top-in light temperature control silicon light packaging system with a spectrum reference locking function, relates to the technical fields of silicon-based optoelectronic device packaging and spectrum detection, and comprises a top-in light temperature control silicon light packaging module with a spectrum reference locking function, a control unit electrically connected with the temperature control silicon light packaging module, and a data processing unit connected with the temperature control silicon light packaging module. The control unit is used for acquiring the output characteristics of a spectrum reference unit and generating a control signal according to the output characteristics. The data processing unit is used for acquiring and processing a spectrum detection signal. The application introduces a spectrum reference unit into a silicon light chip, and actively regulates and controls based on the output characteristics of the spectrum reference unit by using a thermoelectric refrigeration unit, so that stable control of the spectrum state of the silicon light chip is realized, and the limitation caused by only relying on temperature value control in the prior art is overcome.

Description

Technical Field

[0001] This invention relates to the field of silicon-based optoelectronic device packaging and spectral detection technology, specifically a top-in light temperature-controlled silicon photopackaging system with spectral reference locking function. Background Technology

[0002] Silicon photonics chips are widely used in gas detection, biosensing, environmental monitoring, and portable spectral analysis due to their advantages such as small size, mass production capability, and ease of system integration. However, silicon materials and their optical structures are highly sensitive to temperature changes, and the spectral response of silicon photonics devices typically drifts significantly with temperature variations, with typical drift coefficients reaching tens to hundreds of picometers per degree Celsius.

[0003] In existing technologies, common solutions include controlling the ambient temperature of the device via an external temperature control module or performing post-processing compensation on the spectral data at the system level. However, these methods generally have the following shortcomings: First, the temperature control object is usually the environment or the package casing, which is difficult to accurately reflect the actual operating state of the silicon photonics chip; second, control methods based solely on temperature values ​​cannot effectively cope with changes in thermal resistance inside the package, thermal gradients, and spectral shifts caused by long-term aging; third, post-processing algorithms rely on external calibration, making it difficult to maintain the consistency of the spectral reference during long-term operation or in complex environments.

[0004] Therefore, there is an urgent need for a packaging module that can directly constrain and lock the spectral state at the device level, so that silicon photonics spectral chips can maintain a stable and repeatable spectral response under different environmental conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a top-in light temperature-controlled silicon photopackage system with spectral reference locking function to solve the problems raised in the prior art.

[0006] To achieve the above objectives, the present invention provides a silicon photonics packaging module and system for high-stability spectral measurement applications, particularly a top-in light ceramic packaging module that achieves spectral state locking through the coordinated operation of an on-chip spectral reference unit and a thermoelectric cooling unit. The system includes: a top-in light temperature-controlled silicon photonics packaging module with spectral reference locking function, a control unit electrically connected to the temperature-controlled silicon photonics packaging module, and a data processing unit connected to the temperature-controlled silicon photonics packaging module. The control unit is used to acquire the output characteristics of the spectral reference unit and generate a control signal based on the output characteristics; the data processing unit is used to acquire and process the spectral detection signal.

[0007] According to the above technical solution, the top-input temperature-controlled silicon photonics packaging module with spectral reference locking function includes: a packaging shell, the packaging shell defining an internal cavity; a thermoelectric cooling unit disposed within the packaging shell; a silicon photonics chip disposed on the thermoelectric cooling unit; an electrical lead-out structure electrically connected to the silicon photonics chip; and an optical incident structure disposed in conjunction with the packaging shell for guiding external light signals to be incident from the top of the package onto the silicon photonics chip.

[0008] According to the above technical solution, the silicon photonic chip includes at least one spectral detection unit and at least one spectral reference unit, wherein the spectral reference unit is configured to generate stable reference spectral features under predetermined spectral conditions.

[0009] According to the above technical solution, the thermoelectric cooling unit is configured to actively regulate the working state of the silicon photonic chip based on the output characteristics of the spectral reference unit, so as to keep the output characteristics of the spectral reference unit within a preset range.

[0010] According to the above technical solution, the spectral reference unit and the spectral detection unit are integrated on the same silicon photonic chip and are both located within the same thermally controlled region by the thermoelectric cooling unit. This structure allows the spectral changes of the spectral reference unit to accurately reflect the actual operating state of the spectral detection unit.

[0011] According to the above technical solution, the spectral reference unit can be an optical structure that does not directly participate in the detection of the object under test, and its spectral response is affected by the intrinsic properties of silicon material and temperature.

[0012] According to the above technical solution, the control target of the thermoelectric cooling unit is not limited to a specific temperature value, but dynamically adjusts its driving state according to the deviation between the output spectral characteristics of the spectral reference unit and the preset reference spectral characteristics, thereby realizing the locking of the spectral state of the silicon photonic chip.

[0013] According to the above technical solution, the optical incident structure is disposed in the top region of the package housing, so that the external light signal is incident in a direction approximately perpendicular to the surface of the silicon photonic chip.

[0014] According to the above technical solution, it also includes: the system uses the output wavelength of the spectral reference unit as the feedback signal.

[0015] Compared with existing technologies, the beneficial effects of this invention are as follows: Addressing the industry pain point of spectral inaccuracy caused by temperature drift and external environmental disturbances in silicon photonic chips under complex operating conditions, this solution innovatively introduces a spectral reference locking mechanism, transforming the system control paradigm from "indirect temperature control compensation" to "direct spectral locking." By integrating a highly stable spectral reference unit within the chip and acquiring its spectral signal in real time, the system can dynamically calculate the absolute offset of the chip's actual spectrum under the current operating state. Furthermore, a feedback control algorithm is used to directly drive the chip's built-in thermo-optical or electro-optical tuning actuator, achieving closed-loop, high-precision control of the output spectral state. This physically suppresses the impact of common-mode interference such as temperature fluctuations, thermal stress, and mechanical vibration on the optical path, enabling the locking accuracy to overcome the inherent bottlenecks of traditional temperature control solutions.

[0016] Meanwhile, this application completely eliminates the strong reliance on external negative temperature coefficient (NTC) thermistor readings in traditional designs. Traditional methods require sensing the chip case temperature via the NTC, then combining complex thermodynamic models and multi-temperature calibration curves to indirectly estimate the chip junction temperature and corresponding wavelength drift. This not only introduces temperature measurement delay, model errors, and individual sensor variations, but also necessitates re-executing the tedious temperature cycling calibration process every time a module is replaced or the environment changes. In contrast, this solution directly uses the output wavelength of the spectral reference unit as the unique and true feedback signal, constructing a calibration-free control loop where "spectrum equals temperature, wavelength equals error." Since the reference unit and the signal optical path share the same physical environment of the chip substrate, its wavelength deviation signal naturally includes the combined effects of all environmental variables. Therefore, the system no longer needs to distinguish interference sources or establish complex indirect mapping models, greatly simplifying the control algorithm and eliminating long-term stability risks caused by NTC aging, changes in contact thermal resistance, and calibration data drift.

[0017] At the engineering implementation level, this architecture is integrated into an ultra-compact package module. Based on the designed optical path folding and optoelectronic hybrid integrated layout, the reference unit, beam splitter, and control circuit are highly integrated. The module's form factor conforms to mainstream optical module packaging standards and is directly compatible with existing communication and sensing device interfaces. It contains no moving optical components and is assembled entirely using surface mount technology (SMT) and automated coupling soldering, which not only greatly improves its vibration and shock resistance but also gives the module high repeatability and test consistency, fully adapting to the needs of large-scale automated production lines. This compact and standardized design, coupled with its requirement for no external sensors or user-end calibration, significantly reduces system integration difficulty and bill of materials costs. It provides a high-performance and cost-effective engineering solution for silicon photonics chips in applications with stringent long-term stability and reliability requirements, such as data center optical interconnects, LiDAR, medical spectral analysis, and aerospace optical sensing, demonstrating strong market conversion and large-scale application prospects. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a temperature-controlled silicon photonic packaging module of a top-in light temperature-controlled silicon photonic packaging system with spectral reference locking function according to the present invention. In the figure, 1: bonding alloy wire; 2: test spectrum functional area; 3: high thermal conductivity material layer; 4: metal connection layer; 5: grating coupling structure; 6: glass cover plate; 7: reference spectrum functional area; 8: thermistor; 9: TEC cooling chip; 10: ceramic base. Detailed Implementation

[0019] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example: In this application, a top-in light temperature-controlled silicon photonic packaging system with spectral reference locking function is provided. The system includes: a top-in light temperature-controlled silicon photonic packaging module with spectral reference locking function, a control unit electrically connected to the temperature-controlled silicon photonic packaging module, and a data processing unit connected to the temperature-controlled silicon photonic packaging module. The control unit is used to acquire the output characteristics of the spectral reference unit and generate control signals based on the output characteristics. The control unit periodically acquires the output spectral position or characteristic parameters of the spectral reference unit and compares them with preset reference values. Based on the comparison results, the control unit adjusts the driving current of the thermoelectric cooling unit to keep the spectral characteristics of the spectral reference unit stable, thereby indirectly ensuring the measurement accuracy of the spectral detection unit. The data processing unit is used to acquire and process the spectral detection signals.

[0021] The top-input temperature-controlled silicon photonics packaging module with spectral reference locking function includes: a packaging shell defining an internal cavity; a thermoelectric cooling unit disposed within the packaging shell; a silicon photonics chip disposed on the thermoelectric cooling unit; an electrical lead-out structure electrically connected to the silicon photonics chip; and an optical incident structure configured in conjunction with the packaging shell for guiding external light signals from the top of the package to the silicon photonics chip.

[0022] In this embodiment, as Figure 1The diagram illustrates a top-incident temperature-controlled silicon photonics packaging module with spectral reference locking function. The packaging housing is a ceramic housing with a ceramic base 10. A bottom metal connection layer 4 is located below the ceramic base 10. A glass cover 6 is located above the ceramic housing. An integrated thermoelectric cooling unit is incorporated within the module. The cold end of the thermoelectric cooling unit uses a TEC (thermoelectric temperature control) cooling chip 9 as the mounting substrate for the silicon photonics chip. A thermistor 8 and the silicon photonics chip are both attached to a high thermal conductivity material layer 3 on the upper surface of the TEC (meaning the temperature at this location is the same as the temperature of the silicon photonics chip), and are connected to the packaging base via bonding wires 1. The temperature of the upper surface of the TEC (i.e., the temperature of the silicon photonics chip) is obtained by measuring the resistance change of the thermistor. The silicon photonics chip has multiple test spectral functional areas 2 and at least one reference spectral functional area 7. After an external incident light signal is introduced through the top grating coupling structure 5, the spectral detection unit is used to detect the object under test, and the spectral reference unit is used to provide a real-time spectral reference.

[0023] The silicon photonic chip includes at least one spectral detection unit and at least one spectral reference unit, wherein the spectral reference unit is configured to generate stable reference spectral features under predetermined spectral conditions.

[0024] The thermoelectric cooling unit is configured to actively regulate the operating state of the silicon photonic chip based on the output characteristics of the spectral reference unit, so as to keep the output characteristics of the spectral reference unit within a preset range.

[0025] The spectral reference unit and the spectral detection unit are integrated on the same silicon photonic chip and are located in the same thermal regulation region controlled by the thermoelectric cooling unit.

[0026] The spectral reference unit may be an optical structure that does not directly participate in the detection of the object under test, and its spectral response is affected by the intrinsic properties of silicon material and temperature.

[0027] The control target of the thermoelectric cooling unit is not limited to a specific temperature value, but rather dynamically adjusts its driving state based on the deviation between the output spectral characteristics of the spectral reference unit and the preset reference spectral characteristics, thereby achieving the locking of the spectral state of the silicon photonic chip.

[0028] The optical incident structure is located in the top region of the package housing, so that external light signals are incident in a direction approximately perpendicular to the surface of the silicon photonic chip.

[0029] The system uses the output wavelength of the spectral reference unit as the feedback signal.

[0030] In this embodiment, based on the above structure, the system uses the output wavelength of the spectral reference unit as the feedback signal. Specifically, this includes: powering on the system and the control unit inputting a preset current to the thermoelectric cooler; scanning the spectral reference unit (such as a microring resonator), recording the current resonant wavelength λcurrent, and comparing it with the preset target resonant wavelength λtarget, which is typically calibrated at a standard temperature T0; during system operation, the control unit continuously monitors the output characteristics of the spectral reference unit, including resonant peak positions and interference fringe phases.

[0031] The deviation ∆λ between the current spectral characteristics and the target characteristics is calculated. That is, the current resonant wavelength λcurrent is used and the difference between it and the preset target resonant wavelength λtarget is calculated. Based on the resulting deviation ∆λ, the required thermoelectric cooler drive current increment ∆ITEC is calculated by the control algorithm and applied to the thermoelectric cooler.

[0032] When ∆λ≈ 0, the system maintains the current thermoelectric cooler state, achieving spectral locking.

[0033] Its specific adjustment methods and control algorithms include: The control unit employs an improved PID algorithm to adjust the thermoelectric cooler current. To avoid integral saturation and slow response, incremental PID is used.

[0034] Where: Input quantity This represents the wavelength error at the current moment k, which indicates reverse current when the input is negative. The preset target resonant wavelength, The resonant wavelength at the current time k. Output quantity. This refers to the adjustment amount of the TEC drive current. The proportional coefficient Kp determines the system's response speed to the current error. If Kp is too large, the system will oscillate; if it is too small, the response will be slow. The integral coefficient Ki is used to eliminate static errors (such as small drifts caused by long-term aging). The derivative coefficient Kd is used to suppress system overshoot and improve stability.

[0035] In this application, if k is 2, Δλ(2) = -0.1nm, Δλ(1) = -0.5nm, and Δλ(0) = 0.1nm, then: ; ; Final drive current : ; in, This represents the final driving current at time k.

[0036] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function, characterized in that: The system includes: a top-in light temperature-controlled silicon photopackage module with spectral reference locking function, a control unit electrically connected to the temperature-controlled silicon photopackage module, and a data processing unit connected to the temperature-controlled silicon photopackage module; The control unit is used to acquire the output characteristics of the spectral reference unit and generate a control signal based on the output characteristics; the data processing unit is used to acquire and process the spectral detection signal.

2. The top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 1, characterized in that: The top-input temperature-controlled silicon photonics packaging module with spectral reference locking function includes: a packaging shell defining an internal cavity; a thermoelectric cooling unit disposed within the packaging shell; a silicon photonics chip disposed on the thermoelectric cooling unit; an electrical lead-out structure electrically connected to the silicon photonics chip; and an optical incident structure configured in conjunction with the packaging shell for guiding external light signals from the top of the package to the silicon photonics chip.

3. The top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 2, characterized in that: The silicon photonic chip includes at least one spectral detection unit and at least one spectral reference unit, wherein the spectral reference unit is configured to generate stable reference spectral features under predetermined spectral conditions.

4. The top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 2, characterized in that: The thermoelectric cooling unit is configured to actively regulate the operating state of the silicon photonic chip based on the output characteristics of the spectral reference unit, so as to keep the output characteristics of the spectral reference unit within a preset range.

5. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 3, characterized in that: The spectral reference unit and the spectral detection unit are integrated on the same silicon photonic chip and are located in the same thermal regulation region controlled by the thermoelectric cooling unit.

6. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 3, characterized in that: The spectral reference unit may be an optical structure that does not directly participate in the detection of the object under test, and its spectral response is affected by the intrinsic properties of silicon material and temperature.

7. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 4, characterized in that: The control target of the thermoelectric cooling unit is not limited to a specific temperature value, but rather dynamically adjusts its driving state based on the deviation between the output spectral characteristics of the spectral reference unit and the preset reference spectral characteristics, thereby achieving the locking of the spectral state of the silicon photonic chip.

8. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 2, characterized in that: The optical incident structure is located in the top region of the package housing, so that external light signals are incident in a direction approximately perpendicular to the surface of the silicon photonic chip.

9. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 1, characterized in that: Also includes: The system uses the output wavelength of the spectral reference unit as the feedback signal.

10. A top-in temperature-controlled silicon photonic packaging system with spectral reference locking function according to claim 1, characterized in that: The control unit is also used to adjust the current of the thermoelectric cooler, specifically including: ； in, The input quantity refers to the wavelength error at the current time k; The wavelength error refers to the previous moment; i refers to the sequence number. Kp is the adjustment amount of the drive current of the thermoelectric cooler; Ki is the proportional coefficient; Kd is the integral coefficient; Kd is the differential coefficient. ； in, The preset target resonant wavelength, Let k be the resonant wavelength at the current time. Final drive current : ； in, This represents the final driving current at time k.

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