基于相变冷却的大功率二极管激光器技术

Large power diode laser of phase-change cooling

设计了一种基于相变冷却方式工作的大功率二极管激光器,该激光器的散热器是基于节流式喷射微槽道相变冷却的原理,使冷却液在微槽中的气化率达到了70%,大幅度提高了冷却效果,减小了冷却液流量,在同样制冷功率条件下,冷却液流量仅为水冷方式的1/10。利用相变冷却器进行了背冷式半导体激光器叠阵封装工艺的研究,采用复合热沉与AuSn硬焊料结合的新型封装工艺,完成了准连续3 kW叠阵的封装。实验测试表明,单元叠阵的输出功率达到3.01 kW,占空比10%,封装间距为1.3 mm,光谱宽度小于3.5 nm。最大功率输出时所需R134a冷却液的流量仅为110 mL/min。

By combining the methods of spray cooling heat transfer and micro-grooves phase change heat transfer,we design a heat sink based on throttle microgrooves phase change cooling theory.It has been proved by experiments that the vaporization rate of the coolant in the microgrooves of the cooler had reached 70%.The cooling efficiency increased rapidly while the coolant flow became smaller and the thermal management unit lighter.At the same time,we investigated the packaging of laser diode stacks with back surface cooling heat sink.Using the new technique of compound heat sink,AuSn alloy solder and the multi interface soldering,we completed the packaging of quasi-continuous wave（QCW） 3 kW laser diode stacks,with a packing spacing of 1.3 mm.It has been proved by experiments that this unit stacks device achieved a 3.01 kW peak output power with duty cycle 10%,and the HWFM of spectrum is smaller than 3.5 nm.The flow rate of the coolant R134a is 110 mL/min,which is about 10 times lower than that of water.