激光烧蚀硅靶下荷电粒子和纳米晶粒的电流响应研究  

Study on Current Response of Charged Particles and Nanocrystalline Grains Produced by Laser Ablation of Silicon

作　　者：褚立志[1] 于燕超 邓泽超[1] 丁学成[1] 赵红东[2] 王英龙[1] 

机构地区：[1]河北大学物理科学与技术学院,保定071002 [2]河北工业大学信息工程学院,天津300401

出　　处：《人工晶体学报》2016年第7期1736-1740,共5页Journal of Synthetic Crystals

基　　金：河北省自然科学基金(A2015201166);国家级大学生创新创业训练计划项目(201410075034);河北省光电信息材料重点实验室资助课题

摘　　要：采用波长为308nm的XeCl脉冲准分子激光器，在5-50Pa的Ar气压下烧蚀高阻抗单晶硅（Si）靶。在烧蚀点正前方、距靶1．5cm处放置一个中心开孔直径为2mm的挡板，挡板后面上下对称放置两个极板，然后串联一个标准电阻接地，电阻大小为10Ω，利用高分辨数字存储示波器记录并测量回路中产生的瞬间电流来研究荷电粒子和纳米晶粒的电流响应。实验结果表明烧蚀产物中的正离子在气压为5Pa时到达极板上数量最多。纳米Si晶粒带正电并且随着气压的增加纳米Si晶粒下落到极板的数量呈现先增大后减小趋势，在气压为8Pa时达到最大值，这与扫描电子显微镜的测量结果基本一致。所得结果为进一步研究烧蚀粒子在环境气体中的输运动力学过程提供了依据。The high resistivity single crystalline Si target was ablated by a XeCl pulsed excimer laser （wavelength 308 nm） at the ambient pressure of 5-50 Pa of pure argon gas. A baffle with 2 mm aperture in the center was placed in front of the ablation dot with the distance of 1.5 cm. Two electrode plates were horizontally symmetrical placed behind the baffle. The underlaid electrode connecting a 10 Ωstandard resistor was earthed. The electric current responsivity was studied by using a high resolution oscilloscope to record and measure the instantaneous current in the loop. The result shows that the number of positive ion arriveing the electrode plates is the largest at the pressure of 5 Pa. The Si nanocrystal particles are positive charged. The number of Si nanocrystal particles first increases and then decreases with the ambient pressure increasing and it reaches a maximum at the pressure of 8 Pa. It is consistent with the results of scanning electron microscopy measure. These results provide foundation for the further investigation of the transport dynamics of the ablated particles in ambient gases by pulsed laser deposition.

关 键 词：脉冲激光烧蚀 纳米SI晶粒 尺寸 电流 

分 类 号：O78[理学—晶体学]