【作者】 杨凯；

【导师】 刘建国；

【作者基本信息】 华中科技大学 ， 光学工程， 2018， 硕士

【摘要】 激光具有亮度高、方向性好、峰值功率高、光斑尺寸小等优点,在科学研究和工业生产中发挥着重要的作用。近年来,激光诱导沉积技术得到了越来越多的关注和研究,被广泛地应用于薄膜制备、微型器件制作、电路修复等领域。激光诱导等离子体沉积技术是激光诱导沉积技术的重要研究方向之一,它具有工序简单、使用灵活、容易实现等突出优点,应用前景巨大。本文利用两种廉价、易维护和加工效率高的激光,即波长为355nm的纳秒脉冲激光和波长为1064nm的纳秒脉冲激光,在普通硅酸盐玻璃表面进行铜材料的沉积实验,较系统地研究了激光能量密度、扫描速度、离焦量、加工次数、光斑搭接率等工艺参数对沉积结果的影响。通过单线条激光诱导等离子体沉积铜实验,确定了紫外激光和红外激光对铜材料的沉积阈值。当紫外激光能量密度达到约8J/cm~2,红外激光能量密度达到约12.5J/cm~2时,才会有明显的沉积现象发生。此外,激光扫描速度、离焦量、加工次数等都会对沉积线条的线宽和形貌有明显影响,而且这两种激光作用下沉积线条的尺寸变化规律类似。在大面积铜层沉积过程中,对比研究了这两种激光在不同激光参数下铜沉积层的微观形貌、沉积厚度、表面粗糙度的变化情况,此时激光光斑搭接率是重要的影响因素。光斑搭接率过大会导致铜沉积失败,所以能实现铜有效沉积的合适紫外激光光斑搭接率范围为-20%~50%,红外激光光斑搭接率范围为-20%~40%。在此范围内,随着光斑搭接率的增加,紫外激光作用下铜沉积层微观形貌由坑蚀变为横向沟槽,而红外激光作用下仅发现铜颗粒在玻璃表面的吸附堆积。这两种激光作用下,铜沉积层厚度、表面粗糙度均呈现先增加后减小的趋势。对铜沉积层的X射线衍射(XRD)分析和玻璃表面结构性能分析表明,在激光诱导等离子体沉积的过程中,铜沉积层没有可观察到的氧化现象发生,铜元素有可能扩散到玻璃内部;紫外激光在沉积发生的同时对玻璃的刻蚀作用大于红外激光。对激光诱导等离子体沉积的铜层进一步研究发现,尽管铜沉积层可作为化学镀铜的催化活性中心,但由于大部分铜颗粒附着在玻璃表面及玻璃表面的粗糙度过小等原因,使得铜层的结合强度较差。因此该技术在目前情况下,只适合用在对金属层结合强度要求不高的场合。这项技术与计算机技术、数控机床技术等结合可以方便地制备各种复杂的图案,如书写文字、绘制图画、颜色标记等。更多还原

【Abstract】 Laser has played a very important role in scientific research and industrial production because of its high brightness,good directivity,high peak power and small spot size.In recent years,laser induced deposition technology has attracted more and more attention,and has been widely used in the fields of thin film fabrication,micro device fabrication,circuit repair,and so on.Laser induced plasma deposition technique is one of the most important research area of laser induced deposition technology.It has huge application prospects because of its advantages of simple process,high flexibility,easy realization,etc.In this thesis,two inexpensive,easily-maintained and high-efficiency lasers,i.e.,nanosecond pulsed lasers with a wavelength of 355nm and nanosecond pulsed lasers with a wavelength of 1064nm,were used to deposit copper materials on the surface of silicate glass.The influences of laser processing parameters including energy density(fluence),scan speed,defocus,number of processing,spot overlap,etc.on the deposition results were explored.The deposition fluence thresholds of ultraviolet(UV)laser and infrared(IR)laser were determined by laser induced plasma deposition of single copper line.When the UV laser energy density reached 8J/cm~2 and the IR laser energy density reached 12.5J/cm~2,obvious deposition phenomena were observed.In addition,laser scan speed,defocus,number of processing,etc.had a significant effect on the line width and morphology of the deposited lines,and the variation trend of the line width from the two lasers was similar.In the fabrication of large-area copper layer,the variations of the morphology,deposition thickness and surface roughness of the copper deposition layer under different lasers and laser parameters were investigated.Here,laser spot overlap was found to be an important factor.If the spot overlap was too high,the deposition of copper would fail.Therefore,the spot overlap of the UV laser was limited in the range of-20%to 50%,and that of the IR laser was in the range of-20%to 40%.In these ranges,with the increase of the spot overlap,the morphology of the copper deposition layer changed from pit erosion to horizontal groove.For IR laser,the copper particles were accumulated on the glass surface.The thickness and surface roughness of copper deposition layer under the irradiation of two lasers increased first and then decreased.The X-ray diffraction(XRD)analysis of the copper deposition layer and the analysis of the structure and properties of the glass surface showed that,during the laser induced plasma deposition,no observable oxidation of the copper deposition layer occurred,and the element copper might diffuse into the interior of the glass.Additionally,it was found that the UV laser had a stronger etching effect on the glass.The further study on the copper layer by laser induced plasma deposition showed that the copper deposition layer could serve as a catalytically active center for electroless copper plating.However,the adhesion of the copper layer was poor because most of the copper particles attached to the surface of glass and the surface roughness of the glass was too small.Therefore,in the current situation,this technique was only suitable for the application of lower-adhesion-strength copper layer.This technique,combined with computer and numerical control machine,could easily realize the fabrication of complex patterns,text,drawing pictures,color marks,etc.更多还原