SLD transmitting assembly

Abstract

The invention provides an SLD emission assembly, which comprises an SLD chip and a substrate, the substrate has thermal conductivity, the SLD chip is fixed on the substrate, and the SLD emission assembly also comprises an adjustable resistor assembly; the adjustable resistor assembly is electrically connected with the semiconductor cooler, and the cooling end of the semiconductor cooler is connected with the substrate. According to the technical scheme provided by the invention, the preparation of the SLD transmitting assemblies with multiple spectral bandwidth specifications can be realized only by preparing the SLD transmitting assembly with one spectral bandwidth specification and adjusting the resistance value of the adjustable resistor assembly before leaving a factory, and the manufacturing cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically, to an SLD (Semiconductor Display Device) emitter assembly. Background Technology

[0002] The spectral bandwidth of existing SLDs is typically fixed at the factory; for example, Thorlabs' SLD850S series offers a fixed 3dB bandwidth of 60nm or 55nm. This design has significant limitations for different applications. For instance, in OCT imaging systems, a wider spectral bandwidth (typically >50nm) is needed to achieve high axial resolution, while some research-grade applications may require bandwidth exceeding 80nm. However, in fiber optic gyroscopes (FOGs), a balance between bandwidth and coherence is required, typically necessitating a moderate bandwidth of 30-50nm. Existing products cannot dynamically adjust the bandwidth. To meet different customer needs, manufacturers must pre-produce SLDs with various bandwidth specifications, requiring the maintenance of multiple production lines and inventory, leading to increased costs. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide an SLD transmission component that can improve the problem of increased costs caused by the inability to dynamically adjust bandwidth.

[0004] To achieve the above technical objectives, the technical solution adopted in this application is as follows:

[0005] This application provides an SLD emission assembly, including an SLD chip and a substrate. The substrate is thermally conductive, and the SLD chip is fixed on the substrate. The assembly also includes:

[0006] Adjustable resistor assembly;

[0007] A semiconductor cooler, wherein the adjustable resistor assembly is electrically connected to the semiconductor cooler, and the cooling end of the semiconductor cooler is connected to the substrate.

[0008] Furthermore, the adjustable resistor assembly includes an adjustable resistor and a thermistor;

[0009] The adjustable resistor, the thermistor, and the semiconductor cooler are connected in sequence.

[0010] Furthermore, it also includes heat sinks;

[0011] The cooling end, heat sink, and substrate are connected in sequence.

[0012] Furthermore, the SLD emission assembly also includes:

[0013] Fiber optic components, including optical fibers;

[0014] A support block, on which the optical fiber assembly is disposed;

[0015] The position of the support block corresponds to the P-type semiconductor of the SLD chip, so that the light emitted by the P-type semiconductor is focused into the optical fiber.

[0016] Furthermore, the support block is fixed to the heat sink.

[0017] Furthermore, it also includes:

[0018] The detection component receives the backlight from the SLD, obtains the intensity of the backlight, and obtains the luminous power of the SLD chip based on the intensity of the backlight.

[0019] Furthermore, obtaining the luminous power of the SLD chip based on the intensity of the backlight includes:

[0020] The luminous power is obtained based on the intensity of the backlight and a preset algorithm;

[0021] The preset algorithm is as follows:

[0022]

[0023] P main This indicates the luminous power;

[0024] K0 represents the backlight ratio coefficient at the calibrated temperature, which is used to characterize the ratio of the luminous power to the backlight power of the SLD chip;

[0025] α represents the temperature first-order coefficient of the backlight scaling factor;

[0026] ΔT represents the difference between the current temperature and the calibrated temperature, where the current temperature is obtained by reading the resistance of the thermistor;

[0027] I PD This indicates the current signal generated when the backlight illuminates the diode of the detection component;

[0028] I dark,0 This represents the dark current of the diode in the detection component at the calibrated temperature.

[0029] R PD (T0) represents the responsivity of the diode in the detection component at the calibrated temperature;

[0030] β represents the temperature coefficient of the diode in the detection component.

[0031] Furthermore, the thermistor is disposed on the side of the SLD chip, so that the heat emitted by the SLD chip can be conducted to the thermistor.

[0032] The invention employing the above technical solution has the following advantages:

[0033] In the technical solution provided in this application, an adjustable resistor component is set and electrically connected to a semiconductor cooler. When the adjustable resistor component and the semiconductor cooler form a circuit, the cooling capacity of the semiconductor cooler can be adjusted by adjusting the current value of the circuit. Since the cooling end of the semiconductor cooler is connected to the substrate, and the substrate has thermal conductivity, the cooling capacity can adjust the heat of the SLD chip, thereby adjusting the spectral bandwidth of the SLD chip. This allows for the fabrication of SLD emission components with multiple spectral bandwidth specifications by simply preparing one type of SLD emission component and adjusting the resistance value of the adjustable resistor component before shipment, thus reducing manufacturing costs. Attached Figure Description

[0034] This application can be further illustrated by the non-limiting embodiments given in the accompanying drawings. It should be understood that the following drawings only illustrate some embodiments of this application and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained from these drawings without any inventive effort.

[0035] Figure 1 This is a schematic diagram of the structure provided for an embodiment of this application.

[0036] Icons: 1-Adjustable resistor; 2-Detection component; 3-Support block; 4-Heat sink; 5-Fiber optic assembly; 6-Semiconductor cooler; 7-Substrate; 8-Thermistor; 9-SLD chip. Detailed Implementation

[0037] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that similar or identical parts are referred to by the same reference numerals in the drawings or description. Implementations not shown or described in the drawings are forms known to those skilled in the art. In the description of this application, terms such as "first" and "second" are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0038] To address the problems raised in the background art, this embodiment proposes an SLD transmitting component, such as... Figure 1 As shown, the device includes an SLD chip 9, a substrate 7, an adjustable resistor assembly, and a semiconductor cooler 6. In this embodiment, the substrate 7 is a eutectic substrate, which has thermal conductivity. A eutectic substrate refers to a structure in which the chip and substrate 7 materials (such as tungsten copper, diamond, aluminum nitride, etc.) are bonded using eutectic bonding technology. Its core advantage lies in its high thermal conductivity and matching coefficient of thermal expansion. The eutectic substrate has high thermal conductivity and good heat dissipation capabilities, which is beneficial for the heat conduction of the semiconductor cooler 6, thereby enabling rapid adjustment of the spectral bandwidth.

[0039] In this embodiment, the adjustable resistor assembly can be manually adjusted in resistance value. The adjustable resistor assembly includes an adjustable resistor 1 and is electrically connected to the thermoelectric cooler 6. The cooling end of the thermoelectric cooler 6 is connected to the substrate 7. By connecting the adjustable resistor assembly to a first constant voltage power supply, the first constant voltage power supply, the adjustable resistor assembly, and the thermoelectric cooler 6 form a temperature control loop. By adjusting the resistance value of the adjustable resistor assembly, the current value of the temperature control loop is adjusted, thereby changing the current of the thermoelectric cooler 6 and ultimately changing the cooling capacity of the cooling end of the thermoelectric cooler 6. The formula for the cooling capacity is as follows:

[0040] Q = αIT

[0041] Where: Q is the cooling capacity, α is the Seebeck coefficient, and T is the ambient temperature.

[0042] Since the cooling end of the semiconductor cooler 6 is connected to the substrate 7, the cooling capacity released by the semiconductor cooler 6 is transferred to the SLD chip 9 through the substrate 7, thereby controlling the spectral bandwidth of the SLD chip 9.

[0043] The spectral bandwidth of the SLD chip 9 is closely related to the carrier distribution and band structure of its active region. As temperature increases, the thermal motion of carriers (electrons and holes) intensifies, broadening the energy distribution and resulting in an expanded wavelength range for luminescent recombination (spectral broadening). The gain slightly decreases with increasing temperature (negative temperature coefficient), leading to a redshift in the emission wavelength and an increase in the gain spectral width. Conversely, as temperature decreases, the carrier energy distribution becomes concentrated, resulting in a narrower spectrum.

[0044] Therefore, in this embodiment, the relationship between the resistance adjustment of the adjustable resistor component and the spectral bandwidth of the SLD chip 9 can be calibrated through calibration experiments, thereby determining the mapping relationship between the resistance adjustment and the spectral bandwidth of the SLD chip 9.

[0045] When a wide spectrum (high axial resolution) is required, the resistance of the adjustable resistor component is increased, the cooling capacity of the semiconductor cooler 6 is reduced, the SLD temperature is increased, and the spectrum is broadened.

[0046] When a narrow spectrum is needed (to reduce noise), the resistance of the adjustable resistor component is reduced, the cooling capacity of the semiconductor cooler 6 increases, the SLD is cooled down, and the spectrum is narrowed.

[0047] In this embodiment, the semiconductor cooler 6 achieves cooling through the Peltier effect, a type of thermoelectric effect that refers to the phenomenon of heat absorption or release at the junction when current flows through a circuit composed of two different conductors (or semiconductors). The semiconductor cooler 6 can also achieve precise temperature control of the SLD chip 9 by reading the resistance value of the adjustable resistor component.

[0048] In this embodiment, the adjustable resistor assembly includes an adjustable resistor 1 and a thermistor 8, which are electrically connected in sequence to the adjustable resistor 1, the thermistor 8, and the semiconductor cooler 6. The thermistor 8 is disposed on the side of the SLD chip 9, allowing heat emitted by the SLD chip 9 to be conducted to the thermistor 8.

[0049] In this embodiment, the thermistor 8 is used to monitor the temperature of the SLD chip 9 in real time, and the resistance of the thermistor 8 decreases as the temperature increases. The adjustable resistor 1 is an adjustment element for setting the target temperature by the user, used to adjust the SLD chip 9 to the target spectral bandwidth. The semiconductor cooler 6 is used to control cooling / heating by the direction of current.

[0050] Core principle: Thermistor 8 and adjustable resistor 1 are connected in series to form a voltage divider circuit. The voltage at the voltage divider point reflects the actual temperature (resistor 8 resistance value) and the user-set temperature (adjustable resistor 1 resistance value). The control circuit drives the TEC through the difference in voltage at the voltage divider point, forming a closed-loop feedback control.

[0051] In this embodiment, the thermistor 8 is an irreplaceable real-time temperature sensor, while the adjustable resistor 1 is only used to set the spectral bandwidth. If the adjustable resistor 1 is directly connected to the semiconductor cooler 6, the system will lose its temperature feedback capability, resulting in a severe decrease in temperature control accuracy. The thermistor 8 is directly mounted near the SLD chip 9 (e.g., on the substrate 7) to monitor the temperature of the SLD chip 9 in real time. Its thermistor 8 changes with temperature (e.g., for an NTC thermistor 8, temperature ↑ → resistance ↓), converting the temperature signal into an electrical signal and feeding it back to the control circuit. The control circuit compares the actual temperature with the set value and can also dynamically adjust the direction and magnitude of the cooler current, forming a closed-loop regulation. The thermistor 8 is close to the SLD chip 9 and the substrate 7, directly contacting the chip's heat source, ensuring the real-time nature and accuracy of temperature monitoring.

[0052] The SLD emission assembly in this embodiment also includes a heat sink 4, which is fixed to the upper surface of the semiconductor cooler 6 and in close contact with the substrate 7 (through thermally conductive adhesive or welding), forming a core heat conduction path from the SLD chip 9 to the external environment. Therefore, in this embodiment, the cooling end of the semiconductor cooler 6, the heat sink 4, and the substrate 7 are connected in sequence. The cooling capacity generated by the cooling end of the semiconductor cooler 6 is transferred to the substrate 7 through the heat sink 4, and then to the SLD chip 9 through the substrate 7.

[0053] The heat sink 4 is typically a metal block structure (such as copper or aluminum) that covers the cooling end surface of the semiconductor cooler 6 and is aligned with the substrate 7 and the SLD chip 9 area to ensure rapid heat dissipation from the chip. The heat sink 4 can extend to the vicinity of the support block 3 of the optical fiber assembly 5 to prevent the optical fiber from deviating from its optical path due to temperature expansion.

[0054] The arrangement of heat sink 4 has the following advantages:

[0055] Efficient thermal conductivity: The SLD chip 9 generates heat during operation (especially under high drive current), and the substrate 7 transfers the heat to the heat sink 4. The heat sink 4 uses a highly thermally conductive material (such as copper, with a thermal conductivity of approximately 400 W / m·K) to distribute the heat evenly, preventing localized overheating of the SLD chip 9 that could lead to wavelength drift or damage.

[0056] Mechanical support and fixation: The heat sink 4 provides rigid support for the substrate 7, SLD chip 9, and thermistor 8 to prevent component displacement caused by vibration or external force. By fixing the fiber optic support block 3, the optical path of the fiber optic assembly 5 and the SLD chip 9 is ensured to be aligned for a long time to avoid mismatch due to temperature deformation.

[0057] Heat sink 4 serves as the heat transfer medium between semiconductor cooler 6 and SLD chip 9. When semiconductor cooler 6 cools or heats through the Peltier effect, heat is rapidly transferred through heat sink 4, enabling dynamic adjustment of the temperature of SLD chip 9.

[0058] The SLD transmitting assembly in this embodiment also includes an optical fiber assembly 5 and a support block 3.

[0059] In this embodiment, the support block 3 can be fixed to the heat sink 4 for the following reasons:

[0060] When the coefficients of thermal expansion of the heat sink 4 (usually copper / aluminum) and the support block 3 (which may be made of the same material or a low CTE alloy) are matched, they expand / contract synchronously when the temperature changes, avoiding lateral displacement between the optical fiber and the SLD chip 9, thereby maintaining optical coupling efficiency (e.g., >95%).

[0061] Heat sink 4, as a high-rigidity metal block, provides a vibration-resistant foundation for support block 3.

[0062] After the support block 3 comes into contact with the heat sink 4, its temperature is buffered by the high heat capacity of the heat sink 4, the local temperature difference is reduced, the fiber stretching caused by the temperature gradient is reduced, and thus wavelength drift is suppressed.

[0063] In this embodiment, the optical fiber assembly 5 includes an optical fiber. The optical fiber assembly 5 is disposed on the support block 3. The position of the support block 3 corresponds to the P-type semiconductor of the SLD chip 9, so that the light emitted by the P-type semiconductor is focused into the optical fiber.

[0064] In this embodiment, a detection component 2 is provided to receive the backlight of the SLD, obtain the intensity of the backlight, and obtain the luminous power of the SLD chip 9 based on the intensity of the backlight.

[0065] Based on the backlight intensity, the luminous power of SLD chip 9 is obtained, including:

[0066] The luminous power is obtained based on the backlight intensity and a preset algorithm;

[0067] The default algorithm is:

[0068]

[0069] P main Indicates luminous power;

[0070] K0 represents the backlight ratio coefficient at the calibration temperature, which is used to characterize the ratio of the luminous power to the backlight power of the SLD chip 9.

[0071] α represents the temperature first-order coefficient of the backlight scaling factor;

[0072] ΔT represents the difference between the current temperature and the calibrated temperature, where the current temperature is obtained by reading the resistance of thermistor 8;

[0073] I PD This indicates the current signal generated when the backlight shines on the diode of the detection component 2;

[0074] I dark,0 This indicates the dark current of the diode in detection component 2 at the calibrated temperature;

[0075] R PD (T0) represents the responsivity of the diode in detection component 2 at the calibrated temperature;

[0076] β represents the temperature coefficient of the diode in detection component 2. β is marked when detection component 2 leaves the factory and does not need to be calibrated here.

[0077] In this embodiment, K0 is calibrated in the following manner, for example:

[0078] The SLD chip 9 was placed in the constant temperature chamber (T0 = 25℃, assuming T0 is the calibration temperature) and run.

[0079] First, the constant temperature chamber was shielded from light, and the dark current I of the diode in detection component 2 was measured. dark，0 The main output power P was measured using a standard power meter. main Then, the backlight current I of SLD chip 9 was measured. PD Finally, K0 is calculated according to the following formula, and the calibration of K0 is completed.

[0080]

[0081] The temperature of the incubator was set to 45℃ and 5℃ respectively (T0, T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T2high and T low ), and then T high and T low Under the given conditions, repeat the above steps to obtain I. dark，high and I dark，low Then, using the following formula, α can be calculated.

[0082]

[0083] In this embodiment, the adjustable resistor 1 is connected in series with the thermistor 8. By adjusting the resistance value of the adjustable resistor 1, the temperature of the die is changed, thereby adjusting the spectral bandwidth of the SLD chip 9. The detection component 2 is a component for monitoring the laser's emission power. It achieves real-time monitoring of the laser's emission power by detecting the intensity of the laser's backlight (i.e., reverse emission).

[0084] The support block 3 is fixed on the heat sink 4, the fiber optic assembly 5 is aligned with the SLD chip 9, the light emitted by the SLD chip 9 is focused into the fiber, and then the fiber optic assembly 5 is fixed on the support block 3 to achieve stable fiber optic light output.

[0085] Heat sink 4 serves to fix, support, and conduct heat between the substrate 7 and the semiconductor cooler 6.

[0086] The fiber optic assembly 5 is used to focus the light emitted by the SLD chip 9 into the fiber optic cable.

[0087] The semiconductor cooler 6 utilizes the Peltier effect of semiconductor materials to achieve cooling, and achieves precise temperature control of the SLD chip 9 by reading the resistance value of the thermistor 8 + adjustable resistor 1.

[0088] The eutectic substrate utilizes eutectic bonding technology to achieve a reliable connection between the chip, the thermistor 8, and the substrate 7.

[0089] Thermistor 8: A sensitive element whose resistance changes significantly with temperature, used for temperature measurement.

[0090] SLD chip 9 is a superluminescent diode that emits laser light in the 850nm band.

[0091] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An SLD (Surface Mount Technology) emission assembly, comprising an SLD chip and a substrate, wherein the substrate is thermally conductive, and the SLD chip is fixed on the substrate, characterized in that, Also includes: Adjustable resistor assembly; A semiconductor cooler, wherein the adjustable resistor assembly is electrically connected to the semiconductor cooler, and the cooling end of the semiconductor cooler is connected to the substrate.

2. The SLD transmitting assembly according to claim 1, characterized in that, The adjustable resistor assembly includes an adjustable resistor and a thermistor; The adjustable resistor, the thermistor, and the semiconductor cooler are connected in sequence.

3. The SLD transmitting assembly according to claim 1, characterized in that, It also includes heat sinks; The cooling end, heat sink, and substrate are connected in sequence.

4. The SLD transmitting assembly according to claim 3, characterized in that, The SLD emission assembly also includes: Fiber optic components, including optical fibers; A support block, on which the optical fiber assembly is disposed; The position of the support block corresponds to the P-type semiconductor of the SLD chip, so that the light emitted by the P-type semiconductor is focused into the optical fiber.

5. The SLD transmitting assembly according to claim 3, characterized in that, The support block is fixed to the heat sink.

6. The SLD transmitting assembly according to claim 1, characterized in that, Also includes: The detection component receives the backlight from the SLD, obtains the intensity of the backlight, and obtains the luminous power of the SLD chip based on the intensity of the backlight.

7. The SLD transmitting assembly according to claim 1, characterized in that, The process of obtaining the luminous power of the SLD chip based on the intensity of the backlight includes: The luminous power is obtained based on the intensity of the backlight and a preset algorithm; The preset algorithm is as follows: P main This indicates the luminous power; K0 represents the backlight ratio coefficient at the calibrated temperature, which is used to characterize the ratio of the luminous power to the backlight power of the SLD chip; α represents the temperature first-order coefficient of the backlight scaling factor; ΔT represents the difference between the current temperature and the calibrated temperature, where the current temperature is obtained by reading the resistance of the thermistor; I PD This indicates the current signal generated when the backlight illuminates the diode of the detection component; I dark,0 This represents the dark current of the diode in the detection component at the calibrated temperature. R PD (T0) represents the responsivity of the diode in the detection component at the calibrated temperature; β represents the temperature coefficient of the diode in the detection component.

8. The SLD transmitting assembly according to claim 1, characterized in that, The thermistor is disposed on the side of the SLD chip so that the heat emitted by the SLD chip can be conducted to the thermistor.

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