【作者】 高阳；

【导师】 史铁林； 廖广兰；

【作者基本信息】 华中科技大学 ， 机械制造及其自动化， 2013， 博士

【摘要】 半导体加工技术中的感应耦合等离子体刻蚀技术(Inductively Coupled Plasma，ICP)具有控制精度高、刻蚀垂直度高、大面积刻蚀均匀性好、污染少等优点。其中，ICP-Bosch已经广泛应用于深硅刻蚀。ICP-Bosch刻蚀工艺的特别之处就是采用钝化和刻蚀交替作用，从而达到对硅基底的选择性刻蚀。本文利用ICP-Bosch工艺可以转移光刻胶结构的特性制备出硅基超疏水宽波段抗反射高深宽比微纳结构；基于ICP-Bosch刻蚀工艺的特点，利用交替加工产生的侧壁波纹结构制备出硅基仿Morpho蝶翅鳞片分层微纳结构。首先介绍了ICP-Bosch工艺刻蚀机理。基于ICP-Bosch干法刻蚀工艺良好的掩膜结构转移能力，提出了一种新的有效的方法制备周期性高深宽比管状硅光栅，这些硅光栅拥有亚波长锥形顶部结构。该方法的创新之处是利用衍射干涉光刻工艺制备出拥有亚波长锥形轮廓中空的光刻胶光栅。用严格耦合波分析方法对衍射干涉光刻模型做了理论仿真，并在光刻机上实现衍射干涉光刻，制备出拥有锥形轮廓中空的光刻胶光栅。最后用ICP-Bosch干法刻蚀工艺把锥形轮廓的中空光刻胶光栅转移到硅基底上，加工出顶部是亚波长锥形结构高深宽比管状硅光栅。利用光学测试平台对顶部是锥形结构高深宽比管状硅光栅样品表面的反射光谱进行测量，测量出在硅片表面加工出顶部是亚波长锥形结构高深宽比管状硅光栅结构的样品表面可以在可见光波段和近红外波段将反射率降低到5%以下，实现了宽波段抗反射的性能要求。利用接触角测量仪对制备的顶部是亚波长的锥形结构高深宽比管状硅光栅结构的表面的浸润性能进行了测量，测量得到水滴在锥形结构高深宽比管状硅光栅结构的表面的平均接触角为156.2o，达到超疏水性能的要求。基于ICP-Bosch刻蚀工艺，提出了一种新的制备硅基仿Morpho蝶翅鳞片分层微纳结构的方法。该方法巧妙的利用ICP-Bosch工艺刻蚀和钝化交替刻蚀（111）硅片在{110}晶面所产生的微纳尺度的波纹结构。针对刻蚀步骤中对侧壁波纹结构影响较大的因素：循环时间（刻蚀和钝化时间）、气体流量（SF6和C4F8）、刻蚀步骤中的线圈功率（PC）、刻蚀步骤中的射频功率(PP)做了实验研究，设计出一套可行的方案，用实验方法对（111）硅片中{110}晶面在不同温度和不同浓度的KOH溶液的腐蚀速度做了研究，选用电子束蒸发镀膜工艺为硅基底倾斜蒸发镀膜，在{110}晶面波纹的底部覆盖一层用于湿法腐蚀的掩膜，最后采用各向异性湿法腐蚀工艺制备出硅基分层微纳结构。对制备出的硅基分层微纳结构做了光学性能测试，实验发现，当入射光线垂直分层结构光栅线条方向入射时，测得的最大反射率在紫外波段是小于15%，在可见和近红外波段的反射率为4%左右，大大低于硅光栅在这种入射角度的反射率。对分层微纳结构做了传热性能测试，实验发现，硅基分层微纳结构的最大热流密度比硅光栅的要提高11.2%，比抛光硅片要提高44.6%，说明该结构拥有良好的散热性能。更多还原

【Abstract】 Inductively coupled plasma (ICP) etching process in semiconductor processingtechnology has the merits of high control precision, high etching vertical, a large areaetching uniformity, less pollution. Bosch process has been widely used in the ICP etchingprocess in deep silicon etching.The unique feature of ICP-Bosch etching process is its passivation and etchingalternately so as to achieve the selective and deep etching of the silicon substrate. Basedon the characteristics of the ICP-Bosch etching process，in this thesis，we used ICP-Boschprocess to transfer the photoresist pattern structure producing high aspect ratio micro/nanosilicon structure with super hydrophobic and broadband antireflection properties. It wasfollowed to use the sidewall corrugated structure prepared by alternate etching processingto fabricate silicon hierarchical micro/nano structure bio-inspired by the ridge-lamellaestructures on Morpho scales.The mechanism of ICP-Bosch process etching was firstly introduced. We usedICP-Bosch process to transfer the photoresist pattern structure producing periodic highaspect ratio micro/nano silicon gratings structure with sub-wavelength tapered structureson top of the silicon gratings. The innovation of this approach is the application ofdiffraction interference lithography process to prepare the sub-wavelength hollow andtapered contour photoresist gratings. Diffraction interference lithography was theoreticallysimulated by rigorous coupled wave analysis(RCWA), and achieved diffractionlithography on the aligner. The sub-wavelength hollow and tapered contour photoresistgratings were prepared. The sub-wavelength hollow and tapered contour photoresistgratings were transferred to the silicon substrate by ICP-Bosch process that producedperiodic high aspect ratio silicon tube gratings with sub-wavelength tapered structures onthe top of the gratings. We used an optical test platform to measure the reflectance of highaspect ratio tubular silicon gratings. It was found that the reflectance of periodic highaspect ratio silicon tube gratings with sub-wavelength tapered structures on the top of thegratings was less than5%in the visible band and near-infrared band. Themicro/nano-structure has the broadband antireflection property. We used the contact anglemeasuring instrument to test the wettability of periodic high aspect ratio silicon tubegratings with sub-wavelength tapered structures on the top of the gratings. The averagecontact angle was about156.2othat has reached the standard of the super-hydrophobicproperty.Base on the ICP-Bosch process, a novel method for preparation of biomimeticMorpho silicon hierarchical micro/nano structures was proposed. It was ingenious toutilize the micro/nanoscale corrugated structure on the sidewall of {110} crystal faces thatwere produced by the ICP-Bosch process etching and passivation alternately etching thesilicon wafer. This thesis focuses on the main impact factors that influence on the corrugated structure in the etching step: cycle time (etching and passivation time), the gasflow (SF6and C4F8), coil power (PC) and the RF power (PP) in the etching step byexperimental studies. We designed a feasible solution to measure the etching rate of {110}plane in (111) silicon wafer under the different temperatures and different concentrationsof the KOH solution by experimental methods. Electron beam evaporation coatingtechnology was applied inclined evaporation deposited covering layer on bottom of rippleson the {110} plane as mask for the wet etching. Finally, the silicon hierarchicalmicro/nano structure was prepared by using anisotropic wet etching process. The opticalperformance of the silicon hierarchical micro/nano structure was test. It was found thatwhen the incident light perpendicular to hierarchy grating lines direction, the measuredmaximum reflectance in the ultraviolet band was less than15%and about4%in the visibleand near-infraredband, that was less than the reflectance of the silicon grating in this angleof incidence. The heat transfer of the silicon hierarchical micro/nano structure was test.Compared with silicon grating, the maximum heat flux of the hierarchical micro/nanostructure improved11.2%. Compared with polished silicon, the maximum heat flux of thehierarchical micro/nano structure increased44.6%. Therefore, the structure has a goodcooling performance.更多还原