腔长对高功率单管半导体激光器性能的影响

Influence of Cavity Length on Single Emitter Semiconductor Laser Performance

为了降低高功率单管半导体激光器的结温、提高器件的可靠性,采用波长漂移法对不同腔长激光器的热阻进行测量,在此基础上,研究了芯片腔长对单管激光器结温和可靠性的影响。实验结果表明,在热沉温度20℃和连续输出功率10 W的条件下,腔长为4 mm时器件的结温最低,仅有56.3℃;当热沉温度为30℃时,在已进行的3 200 h老化测试中,4 mm腔长的激光器功率退化率最低,仅为3.09%;利用外推法得到器件的寿命为20 711 h,是2.5 mm腔长激光器寿命的3.42倍。研究发现,激光器芯片的腔长直接影响着器件的结温和可靠性。为提高器件的寿命,高功率单管半导体激光器应选用长腔长的芯片。

In order to reduce the junction temperature and improve the reliability of the high power single emitter semiconductor laser, the thermal resistor of chips with different cavity lengths was measured with the method of wavelength shift. Based on this, effect of cavity length on junction temperature and reliability of the single emitter laser was studied. The experiment results show that when the heat sink temperature is 20 ℃ , the continuous waves output power is 10 W, the cavity length is 4 mm, and the minimum junction temperature of the device is 56.3 ℃. When the heat sink temperature is 30 ℃ , the cavity length is 4 mm, and the lowest degradation rate of the power is 3.09% in 3 200 h life-test. Using the extrapolation method, the lifetime of the device is determined to be 20 711 h. And it is 3.42 times of 2.5 mm cavity length laser life time. This work demonstrates that the cavity length is a critical factor affecting the junction temperature and reliability of the device. In order to improve the lifetime, semiconductor lasers should choose the chips with long cavity length.