纳米Si/SiN_x薄膜的制备及对Nd∶YAG激光器的被动调Q

Preparation of nano-Si/SiN_x film and its application in passive Q-switch of Nd∶YAG laser

为了研究纳米硅镶嵌氮化硅薄膜材料的被动调Q特性,采用射频磁控反应溅射法结合热退火处理在单晶硅衬底上制备该薄膜,用该样品作为可饱和吸收体,在凹-平腔中实现了氙灯抽运Nd∶YAG激光器的被动调Q运转,在抽运重复频率1Hz情况下获得脉宽最小可达19ns的调Q单脉冲输出。并且研究了该薄膜结构特性、激光器参数,如抽运电压、腔长对调Q脉冲输出性能产生的影响。在此基础上,对实验现象产生的原因做了分析讨论。结果表明,纳米硅镶嵌氮化硅薄膜有一定的调Q效果,具有潜在的研究及应用价值。

In order to study passive Q-switch character of the nanoscale-Si-particle embedded in silicon nitride （ nano-Si/ SiNz） thin film, the film was prepared on single crystal silicon by means of radio frequency magnetron reaction sputtering technique and thermal annealing. In the experiment, these samples were inserted as saturable absorber into the resonator, concaveflat cavity was adopted and Nd：YAG was pumped by a xenon lamp,and the Q-switched waveform of 19ns single pulse width was obtained at repetition rate of 1Hz. Furthermore, the influence of structural characteristic, pump voltage and cavity length on the properties of laser output was investigated. Then, these phenomena observed in the experiment was analyzed and discussed based on the theory of passive Q-switch. In conclusion, nano-Si/SiNx film has potential value in research and applications because of its passive Q-switch character.