量子级联激光器热仿真与分析

Thermal Simulation and Analysis of Quantum Cascade Laser

针对大功率量子级联激光器对高散热能力的迫切需求,文章通过有限元法建立了常见器件结构的二维散热模型。在设置的热沉温度为293 K、波长为8.3μm、波导宽为8μm、发热功率为12.4 W的器件模型中,研究了不同器件散热结构和封装结构对量子级联激光器的温度及热通量分布的影响,进而评价器件的散热能力。结果表明,正焊无电镀金双沟道脊器件、正焊有电镀金双沟道脊器件和倒焊器件的最高温度分别为546,409和362 K。在掩埋异质结器件中,正焊无电镀金器件、正焊有电镀金器件、倒焊器件的最高温度分别为404,401和361 K。与使用铜底座相比,使用金刚石底座的掩埋异质结倒焊器件有源区的最高温度为355 K。对模型热通量分布进行了分析,发现掩埋异质结器件的热量分布更加均匀,有源区温度更低,这表明掩埋异质结更适合高功率器件。

Two-dimensional heat-dissipation models of common devices were established using the finite element method to improve the heat-dissipation capacity of quantum-cascade lasers(QCLs).By setting the heatsink temperature to 293 K,wavelength to 8.3μm,waveguide width to 8μm,and thermal power to 12.4 W,the temperature,heat flux distribution,and heat dissipation capabilities of QCLs with different device structures were studied.The results show that the highest temperatures of the epilayer-up-bonded double-channel ridge device without and with electroplated gold were 546 K and 409 K,respectively,while that of the epilayer-down-bonded device was 362 K.For buried heterostructure(BH)devices,the highest temperatures of the epilayer-up-bonded device without and with electroplated gold were 404 K and 401 K,respectively,while that of the epilayer-down-bonded device was 361 K.Compared with the copper submount,the highest temperature of the buried heterostructure epilayer-down-bonded to a diamond submount device was 355 K.Analysis of the heat flux distribution of the models shows that the heat flux of the BH devices is more uniform,and the temperature of the core area is lower,indicating that BH structures are more suitable for high-power devices.