Semiconductor laser array life prediction method based on thermo-optical coupling
By considering the influence of thermal-optical coupling in the semiconductor laser array lifetime prediction, a life prediction method based on thermal-optical coupling is established, which solves the problem of large life prediction deviation in the prior art and achieves more accurate life prediction.
Patent Information
- Application Number
- CN202411708188.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-03-07
AI Technical Summary
When predicting the lifetime of semiconductor laser arrays, the prior art fails to effectively consider the impact of thermal and optical coupling on optical power degradation, resulting in a large deviation from the predicted value and the real value.
The semiconductor laser array life prediction method based on thermal optical coupling is adopted, and by planning sample selection and packaging methods, an accelerated life experiment platform is built, optical power, voltage and thermal resistance are measured, degradation models are established, and the working life under normal temperature conditions is extrapolated.
By considering the impact of thermally-optical coupling on semiconductor laser arrays, the accuracy of lifetime prediction is significantly improved and the deviation between the predicted value and the true value is reduced.
Smart Images
Figure CN119578089A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of semiconductor laser reliability, and in particular to a semiconductor laser array life prediction method based on thermal-optical coupling. Background Art
[0002] Semiconductor laser arrays have the advantages of low threshold current, high photoelectric conversion efficiency, good beam quality, and easy coupling with optical fibers. They have broad application prospects in three-dimensional sensing, optical interconnection, laser pumping, and high reliability.
[0003] However, during the use of semiconductor laser arrays, as the use time increases, its optical power will slowly degrade. When its optical power drops by 30%, it will not be able to meet the application requirements, that is, the device is deemed to have failed. At this time, the use time of the semiconductor laser array is called the life of the semiconductor laser array. In order to accurately predict the life of the semiconductor laser array in a shorter time, an accelerated life test method is usually used, that is, the degradation relationship of the optical power of the semiconductor laser array from the initial working moment to the optical power drop of 5% is tested under two different environmental temperature stresses, and the degradation rate of the optical power is calculated, and then the life of the semiconductor laser array when the optical power drops by 30% is extrapolated. However, when extrapolating the life of the semiconductor laser array, the above method does not consider the influence of the temperature rise caused by thermal-optical coupling during the optical power degradation process on the power consumption and thermal resistance of the semiconductor laser array, which makes the predicted value of the semiconductor laser array life deviate greatly from the actual value. In order to deal with the above problems, there is an urgent need for an accurate prediction method for the life of a semiconductor laser array that takes into account thermal-optical coupling. Summary of the invention
[0004] The present invention discloses a semiconductor laser array life prediction method based on thermal-optical coupling, which is characterized by comprising the following steps:
[0005] 1. A method for predicting the lifetime of a semiconductor laser array based on thermal-optical coupling, comprising the following steps:
[0006] S1. Plan the sample selection and packaging methods of semiconductor laser arrays, and perform unit sample sampling;
[0007] S2. Select working current data, test interval time data, and two ambient temperature stress data according to the type and model of the semiconductor laser array;
[0008] S3, building an accelerated life test platform, and performing accelerated life tests on semiconductor laser arrays under the two environmental temperature stresses and the specified working currents;
[0009] S4. Rapidly determine the consistency of the failure mechanism of the semiconductor laser array under the two environmental temperature stresses. If the failure mechanism changes, the two environmental temperature stress data need to be reselected until the failure mechanism is consistent;
[0010] S5, calculating the optical power degradation rate of the semiconductor laser array, and then determining the power consumption, thermal resistance and optical power degradation model respectively;
[0011] S6. Extrapolate the operating life of the semiconductor laser array at room temperature.
[0012] 2.: The specific method of the accelerated life experiment of the semiconductor laser array in S3 includes the following steps:
[0013] S3.1. Install the semiconductor laser array sample on the accelerated life test platform for temperature control, keep the semiconductor laser array working at a specified current and in a continuous energized working state under the two environmental temperature stresses, and measure the optical power, voltage, and thermal resistance of the semiconductor laser array at the initial moment;
[0014] S3.2, measuring the optical power, voltage, and thermal resistance of the semiconductor laser array respectively according to the test interval time until the optical power decreases by 5%, and recording the degradation time at this time;
[0015] 3. The method for determining the consistency of the failure mechanism in S4 is as follows:
[0016] The failure mechanism of the semiconductor laser array under the two environmental temperature stresses is discriminated. If the degradation time of the semiconductor laser array under the two environmental temperature stresses obeys the Weibull distribution, and the shape parameter and the scale parameter simultaneously satisfy the failure mechanism consistency discrimination relationship, it can be determined that the failure mechanism of the semiconductor laser array is consistent when working within the two environmental temperature stress ranges.
[0017] 4. The calculation method of the optical power degradation rate of the semiconductor laser array in S5, and the modeling method of the power consumption, thermal resistance and optical power degradation model are as follows:
[0018] S5.1. Selecting the median degradation time from the degradation times under the two ambient temperature stresses recorded in S3, respectively, and the corresponding semiconductor laser array is the median semiconductor laser array;
[0019] S5.2. Based on the optical power of the median semiconductor laser array at the initial moment measured in S3.1 and the optical power of the median semiconductor laser array when the optical power drops by 5% measured in S3.2, calculate the degradation rate β of the optical power of the median semiconductor laser array:
[0020]
[0021] Wherein, P0(0) is the optical power of the median semiconductor laser array at the initial moment, P0(t) is the optical power when the optical power of the median semiconductor laser array decreases by 5%, and t is the corresponding degradation time.
[0022] S5.2. Determine a power consumption degradation model based on the optical power and voltage of the median semiconductor laser array measured in S3.1 at the initial moment and the optical power and voltage of the median semiconductor laser array measured in S3.2 when the optical power drops by 5%:
[0023] P d (t) = P d (0)+c×exp(t / d)
[0024] Among them, P d (0) is the power consumption of the median semiconductor laser array at the initial moment, P d (t) is the power consumption corresponding to a 5% drop in optical power of the median semiconductor laser array, t is the corresponding degradation time, and c and d are constants.
[0025] S5.3, according to the thermal resistance of the median semiconductor laser array at the initial moment measured in S3.1 and the thermal resistance of the median semiconductor laser array when the optical power decreases by 5% measured in S3.2, determine the thermal resistance degradation model:
[0026] R th (t) = R th0 +p×exp(t / q)
[0027] Among them, R th0 is the thermal resistance of the median semiconductor laser array at the initial moment, R th (t) is the thermal resistance corresponding to a 5% drop in optical power of the median semiconductor laser array, t is the corresponding degradation time, and p and q are constants.
[0028] S5.4. Determine the optical power degradation model according to the optical power, voltage, and thermal resistance of the median semiconductor laser array measured in S3.1 at the initial moment and the optical power, voltage, and thermal resistance of the median semiconductor laser array measured in S3.2 when the optical power drops by 5%:
[0029]
[0030] Among them, I F is the operating current applied to the semiconductor laser array during the accelerated lifetime experiment, E a is the activation energy, k is the Boltzmann constant, which is 1.38×10 -23 J / K, T is the ambient temperature stress.
[0031] 5. The extrapolation method of the working life of the semiconductor laser array in S6 at room temperature is as follows:
[0032] S6.1. Based on the optical power degradation rate, power consumption, thermal resistance and optical power degradation model of the median semiconductor laser array obtained in S5, under the two ambient temperature stresses and the specified operating current, extrapolate the degradation time corresponding to a 30% drop in optical power of the median semiconductor laser array;
[0033] S6.2. Substitute the degradation time corresponding to a 30% drop in the median semiconductor laser array optical power under the two ambient temperature stresses and the specified operating current into the Arrhenius acceleration model, calculate the activation energy of the semiconductor laser array, and then extrapolate the working life of the semiconductor laser array under normal temperature conditions. BRIEF DESCRIPTION OF THE DRAWINGS
[0034] The objects and advantages of the present invention may be further understood from the following description taken in conjunction with the accompanying drawings. In these drawings:
[0035] Figure 1 The optical power variation curves of the median semiconductor laser array under two environmental temperature stresses from the initial moment to when the optical power drops by 5% over time are illustrated;
[0036] Figure 2 The example shows the curve of the change of power consumption over time of the median semiconductor laser array from the initial moment to when the optical power drops by 5% under two environmental temperature stresses;
[0037] Figure 3 The curves of the change of thermal resistance over time of the median semiconductor laser array from the initial moment to when the optical power drops by 5% under two environmental temperature stresses are illustrated;
[0038] Figure 4 An example of the thermal resistance Rth0 test curve of the median semiconductor laser array at the initial moment under ambient temperature stress TA is shown;
[0039] Figure 5 It is shown that when the optical power decreases by 5%, the degradation time of semiconductor laser array samples under two environmental temperature stresses obeys Weibull distribution.
[0040] Figure 6 An example of the degradation curve of the power consumption of a median semiconductor laser array over time is shown;
[0041] Figure 7 An example of the degradation curve of the thermal resistance of a median semiconductor laser array over time is shown;
[0042] Figure 8 The measured curve of the optical power of the median semiconductor laser array changing with time, the conventional predicted curve and the predicted curve of this embodiment are illustrated. DETAILED DESCRIPTION
[0043] The present invention is described in detail by taking a semiconductor laser array as an example in the present invention, but the present invention is not limited to this.
[0044] A method for predicting the life of a semiconductor laser array based on thermal-optical coupling, characterized in that it comprises the following steps:
[0045] S1. Select 2 groups of semiconductor laser array chip samples, 5 in each group, all using 3030 packaging;
[0046] S2. Since each semiconductor laser array chip sample has 23 semiconductor laser units, the working current I is selected according to the number of units. F The current is 25mA, the test interval is 24h, and the two environmental temperature stresses are T A =50℃ and T B =65℃;
[0047] S3, build an accelerated life test platform, install the semiconductor laser array sample on the built accelerated life test platform for temperature control, and respectively A =50℃ and T B =65℃, keep the semiconductor laser array working at the specified current I F The current is 25 mA and the device is in a continuously powered working state, and the optical power, power consumption and thermal resistance of the semiconductor laser array are measured at the initial moment; thereafter, the optical power P0, voltage V and thermal resistance R of the semiconductor laser array are measured every 24 hours. th A measurement is performed until the optical power drops by 5%. The optical power P0 and power consumption P of the median semiconductor laser array under two ambient temperature stresses from the initial moment to the optical power drop by 5% d Thermal resistance R th The curves of changes over time are as follows Figure 1-3 The thermal resistance R of the median semiconductor laser array at the initial moment is shown in Figure 2. th0 Test curve as Figure 4 And record the stress at ambient temperature as T A =50℃ and T B = The time corresponding to the 5% decrease of optical power at 65°C is t MA =335h and t MB =160h;
[0048] S4, the semiconductor laser array is subjected to an ambient temperature stress of T A=50℃ and T B =65°C. If the degradation time of the semiconductor laser array under the two environmental temperature stresses obeys the Weibull distribution:
[0049]
[0050] Where m is the shape parameter, η is the scale parameter, and AF is the acceleration factor. Ambient temperature stress T A =50℃ shape parameter is m A , the scale parameter is η A , ambient temperature stress T B =65℃ shape parameter is m B , the scale parameter is η B , if the shape parameter m is satisfied at the same time A =m B and the scale parameter η A =AF×η B , where AF is obtained by exp(-E a / (kT A )) and exp(-E a / (kT B )) is obtained, it is determined that the failure mechanism of the semiconductor laser array when operating in the two ambient temperature stress ranges is consistent. The semiconductor laser array is in an ambient temperature stress of T A =50℃ and T B = 65 ° C, the degradation time of the semiconductor laser array sample when the optical power decreases by 5% is imported into SPSS software, and the degradation time distribution is obtained as follows Figure 5 As shown, the shape parameters and size parameters can be obtained at the same time, as shown in the following table:
[0051] Shape parameter m Size parameter η 50℃ 30.06 342.719 65℃ 29.51 160.620
[0052] It can be seen that at the ambient temperature stress T A =50℃ and T B =65℃, when the optical power decreases by 5%, the degradation time of the semiconductor laser array samples all presents Weibull distribution; and the shape parameter m A =m B , the scale parameter η A / η B =2.13, AF = exp(-E a / (323k)) / exp(-E a / (338k))=2.07. Therefore, it can be determined that when the optical power of the semiconductor laser array decreases by 5%, the failure mechanism is consistent when working in the range of 50° C. to 65° C.
[0053] S5, selecting a median degradation time from the degradation times under the ambient temperature stress recorded in S3, and the corresponding semiconductor laser array is the median semiconductor laser array;
[0054] The ambient temperature is T A =50°C as an example, the optical power of the median semiconductor laser array at the initial moment is 85mW, and the optical power when the optical power decreases by 5% is 80.75mW, and the corresponding degradation time t MA The degradation rate of the optical power of the median semiconductor laser array is calculated to be β = 0.013 mW / h.
[0055] According to the optical power and voltage of the median semiconductor laser array at the initial moment and the optical power and voltage when the optical power drops by 5% measured in S3, the constants c=140 and d=267 in the power consumption degradation model are determined, so the power consumption degradation model is P d (t) = 140 + 1.93 × exp (t / 267), the corresponding degradation curve of the power consumption of the median semiconductor laser array over time is as follows Figure 6 As shown;
[0056] According to the thermal resistance of the median semiconductor laser array at the initial moment and the thermal resistance when the optical power drops by 5% measured in S3, the constants p=34.45 and q=232.98 in the thermal resistance degradation model are determined, so the thermal resistance degradation model is R th (t) = 34.45 + 2.34 × exp (t / 232.98), the corresponding degradation curve of the thermal resistance of the median semiconductor laser array over time is as follows Figure 7 As shown;
[0057] According to the optical power, voltage, thermal resistance of the median semiconductor laser array at the initial moment and the optical power, voltage, thermal resistance when the optical power drops by 5% measured in S3, the optical power degradation model is determined:
[0058]
[0059] S6. Extrapolate the working life of the semiconductor laser array under normal temperature conditions. According to the predicted data, the working life of the median semiconductor laser array under the ambient temperature stress of T A =50℃ and T B =65℃, the time when the optical power degrades to 30% is t NA =720h and t NB =360h; Substitute the degradation time into the Arrhenius acceleration model lnt=A+E a / kT, the activation energy of the median semiconductor laser array is calculated to be 0.44 eV, the constant A = -9.21, and the working life of the semiconductor laser array at room temperature is extrapolated to be 15367 h, which is about 1.8 years.
[0060] In addition, in order to verify the correctness of the semiconductor laser array life prediction method based on thermal-optical coupling described in the present invention, when the optical power of the semiconductor laser array drops by 5%, the accelerated life experiment is continued until the optical power of the semiconductor laser array drops by 30%. The optical power of the semiconductor laser array is synchronously tested according to the test interval time to obtain the change curve of the median semiconductor laser array optical power over time, and compared with the optical power change prediction curve of the embodiment of the present invention and the conventional optical power change prediction curve, as shown in FIG. Figure 8 It can be seen that the optical power variation with time prediction curve of the embodiment of the present invention is in good agreement with the experimental curve, and the prediction accuracy is much higher than the conventional semiconductor laser array life prediction method.
Claims
1. A method for predicting the lifetime of a semiconductor laser array based on thermal-optical coupling, characterized in that: The steps include: S1. Plan the sample selection and packaging methods of semiconductor laser arrays, and perform unit sample sampling; S2. Select working current data, test interval time data, and two ambient temperature stress data according to the type and model of the semiconductor laser array; S3, building an accelerated life test platform, and performing accelerated life tests on semiconductor laser arrays under the two environmental temperature stresses and the specified working currents; S4. Under the two environmental temperature stresses, quickly determine the consistency of the failure mechanism of the semiconductor laser array; If the failure mechanism changes, the two environmental temperature stress data need to be reselected until the failure mechanism is consistent; S5, calculating the optical power degradation rate of the semiconductor laser array, and then determining the power consumption, thermal resistance and optical power degradation model respectively; S6. Extrapolate the operating life of the semiconductor laser array at room temperature.
2. The semiconductor laser array lifetime prediction method based on thermal-optical coupling according to claim 1, characterized in that: The specific method of the accelerated lifetime experiment of the semiconductor laser array in S3 comprises the following steps: S3.
1. Install the semiconductor laser array sample on the accelerated life test platform for temperature control, keep the semiconductor laser array working at a specified current and in a continuous energized working state under the two environmental temperature stresses, and measure the optical power, voltage, and thermal resistance of the semiconductor laser array at the initial moment; S3.
2. Measure the optical power, voltage and thermal resistance of the semiconductor laser array respectively according to the test interval time until the optical power drops by 5%, and record the degradation time at this time.
3. The semiconductor laser array lifetime prediction method based on thermal-optical coupling according to claim 1, characterized in that: The method for determining the consistency of the failure mechanism in S4 is as follows: The failure mechanism of the semiconductor laser array under the two ambient temperature stresses is discriminated; if the degradation time of the semiconductor laser array under the two ambient temperature stresses obeys the Weibull distribution, and the shape parameter and the scale parameter simultaneously satisfy the failure mechanism consistency discrimination relationship, it is determined that the failure mechanism of the semiconductor laser array is consistent when working within the two ambient temperature stress ranges.
4. The method for predicting the lifetime of a semiconductor laser array based on thermal-optical coupling according to claim 1, characterized in that: The method for calculating the optical power degradation rate of the semiconductor laser array in S5, and the modeling method of the power consumption, thermal resistance and optical power degradation model are as follows: S5.
1. Selecting the median degradation time from the degradation times under the two ambient temperature stresses recorded in S3, respectively, and the corresponding semiconductor laser array is the median semiconductor laser array; S5.
2. Based on the optical power of the median semiconductor laser array at the initial moment measured in S3.1 and the optical power of the median semiconductor laser array when the optical power drops by 5% measured in S3.2, calculate the degradation rate β of the optical power of the median semiconductor laser array: Wherein, P0(0) is the optical power of the median semiconductor laser array at the initial moment, P0(t) is the optical power when the optical power of the median semiconductor laser array decreases by 5%, and t is the corresponding degradation time; S5.
2. Determine a power consumption degradation model based on the optical power and voltage of the median semiconductor laser array measured in S3.1 at the initial moment and the optical power and voltage of the median semiconductor laser array measured in S3.2 when the optical power drops by 5%: P d (t)=P d (0)+c×exp(t / d) Among them, P d (0) is the power consumption of the median semiconductor laser array at the initial moment, P d (t) is the power consumption corresponding to a 5% drop in the optical power of the median semiconductor laser array, t is the corresponding degradation time, and c and d are constants; S5.3, according to the thermal resistance of the median semiconductor laser array at the initial moment measured in S3.1 and the thermal resistance of the median semiconductor laser array when the optical power decreases by 5% measured in S3.2, determine the thermal resistance degradation model: R th (t)=R th0 +p×exp(t / q) Among them, R th0 is the thermal resistance of the median semiconductor laser array at the initial moment, R th (t) is the thermal resistance corresponding to a 5% drop in optical power of the median semiconductor laser array, t is the corresponding degradation time, and p and q are constants; S5.
4. Determine the optical power degradation model according to the optical power, voltage, and thermal resistance of the median semiconductor laser array measured in S3.1 at the initial moment and the optical power, voltage, and thermal resistance of the median semiconductor laser array measured in S3.2 when the optical power drops by 5%: Among them, I F is the operating current applied to the semiconductor laser array during the accelerated lifetime experiment, E a is the activation energy, k is the Boltzmann constant, which is 1.38×10 -23 J / K, T is the ambient temperature stress.
5. The method for predicting the lifetime of a semiconductor laser array based on thermal-optical coupling according to claim 1, characterized in that: The method for extrapolating the working life of the semiconductor laser array in S6 at room temperature is as follows: S6.
1. Based on the optical power degradation rate, power consumption, thermal resistance and optical power degradation model of the median semiconductor laser array obtained in S5, under the two ambient temperature stresses and the specified operating current, extrapolate the degradation time corresponding to a 30% drop in optical power of the median semiconductor laser array; S6.
2. Substitute the degradation time corresponding to a 30% drop in the median semiconductor laser array optical power under the two ambient temperature stresses and the specified operating current into the Arrhenius acceleration model, calculate the activation energy of the semiconductor laser array, and then extrapolate the working life of the semiconductor laser array under normal temperature conditions.