氧化硅RIE刻蚀工艺研究

利用反应等离子刻蚀技术对SiO₂进行干法刻蚀, 研究了不同刻蚀条件对刻蚀速率、刻蚀选择比、刻蚀面粗糙度、刻蚀均匀性等的影响。分析得出了刻蚀侧壁角度与刻蚀选择比以及抗蚀掩模自身的侧壁角度之间存在的数学关系, 这为如何获得垂直的刻蚀侧壁提供了参考。     

铝—RIE刻蚀工艺

干法刻铝中,ＢＣｌ３添加Ｃｌ２、ＣＨＣｌ３和Ｎ２,可改变Ａｌ的刻蚀速率、Ａｌ对ＳｉＯ２和胶的选择性、线宽和胶膜质量,其中Ｃｌ２流量影响最大。此外,本文还给出了ＲＦ功率和气压的影响。采用适当的气体组合、不太高的功率和不态低的气压（ＢＣｌ３：Ｃｌ２：ＣＨＣｌ３：Ｎ２＝７０ｓｃｃｍ：１５ｓｃｃｍ：１０ｓｃｃｍ：０￣５０ｓｃｃｍ,２００ｍＴｏｒｒ,２００Ｗ）可以实现细线条（０．６μｍ）Ａｌ的刻蚀。     

等离子刻蚀工艺中UV坚膜技术研究

对正性光刻胶进行UV坚膜处理，可有效地保持图形形貌的完整性，并提高抗蚀性能，可消除等离子刻蚀中容易产生的燃胶等现象，但坚膜用起始温度、终点温度、温升速率及UV光照时间等参数对坚膜效果均会产生较大的影响。参数选择不当，同样会产生不良效果。     

聚合物光波导的反应离子刻蚀工艺研究

实验研究了表面粗糙度、侧壁垂直度与各刻蚀参量之间的关系,通过对刻蚀效果的分析,发现在低功率、高CHF3含量、低压强的情况下能获得最小的表面粗糙度;在高功率、50%CHF3含量、低压强的情况下能获得较陡直的波导侧壁.利用优化的刻蚀条件,对PMMA进行刻蚀,得到了均方根粗糙度小、侧壁陡直的波导.实验发现,该刻蚀条件对其他聚合物光波导材料的刻蚀也具有一定的指导意义.     

压电型微悬臂梁制备中RIE刻蚀硅工艺的研究

介绍了一种压电型微悬臂梁的制作工艺流程,重点研究了其中硅的反应离子刻蚀(RIE)工艺,分析了工艺参数对刻蚀速率、均匀性和选择比的影响,提出通过适当调整气体流量、射频功率和工作气压,以加快刻蚀速率,改善均匀性,提高选择比。研究表明,在SF6流量为20 mL/min,射频功率为20 W,工作气压为8.00 Pa的工艺条件下,硅刻蚀速率可以提高到401 nm/min,75 mm(3 in.)基片范围内的均匀性为±3.85%,硅和光刻胶的刻蚀选择比达到7.80。为制备压电悬臂梁或其它含功能薄膜的微结构提供了良好的参考。     

Si材刻蚀速率的工艺研究

在采用混合集成方法制造红外热成像阵列器件中,Si的快速刻蚀去除是一个至关重要的问题,它的刻蚀去除质量直接影响红外热成像器件的性能.介绍了等离子体刻蚀的原理、实验过程和实验方法,通过大量工艺实验和测试详细研究和分析了不同刻蚀气体、射频功率和气体流量等工艺参数对Si刻蚀结果的影响,包括刻蚀速率、刻蚀轮廓垂直度和刻蚀表面粗糙度等.通过研究,获得了Si材刻蚀效果与各种工艺参数之间的变化关系,得到了快速刻蚀Si材的较好的工艺参数.     

RIE工艺参数对4H-SiC刻蚀速率和表面粗糙度的影响

基于4H-SiC材料的微机电系统(MEMS)器件(如压力传感器、微波功率半导体器件等)在制造过程中,需要利用干法刻蚀技术对4H-SiC材料进行微加工.增加刻蚀速率可以提高加工效率,但是调节刻蚀工艺参数在改变4H-SiC材料刻蚀速率的同时,也会对刻蚀表面粗糙度产生影响,进而影响器件的性能.为了提高SiC材料的刻蚀速率并降低刻蚀表面粗糙度,满足4H-SiC MEMS器件研制的需求,本文通过优化光刻工艺参数(曝光模式、曝光时间、显影时间)获得了良好的光刻图形形貌,改善了刻蚀掩模的剥离效果.实验中采用SF6和O2作为刻蚀气体,镍作为刻蚀掩模,分析了4H-SiC反应离子刻蚀工艺参数(刻蚀气体含量、腔体压强、射频功率)对4H-SiC刻蚀速率和表面粗糙度的影响.实验结果表明,通过优化干法刻蚀工艺参数可以获得原子级平整的刻蚀表面.当SF6的流量为330 mL/min,O2流量为30 mL/min,腔体压强为4 Pa,射频功率为300 W时,4H-SiC材料的刻蚀速率可达到292.3 nm/min,表面均方根粗糙度为0.56 nm.采用优化的刻蚀工艺参数可以实现4H-SiC材料的高速率、高表面质量加工.     

硅槽刻蚀工艺研究

集成电路的发展使硅槽的应用越业越广泛，如硅槽隔离和槽电容等等，它们将使器件的性能得到很好的改善。     

0.8μm多晶栅等离子刻蚀研究

文章基于Mintab软件,运用Precision 5000等离子刻蚀技术研究0.8μm多晶栅刻蚀中功率、压力、HBr流量、Cl2流量对刻蚀效果的影响。获得了四个因素对刻蚀效果影响的主次关系,同时由Mintab软件分析获得了各因子效应的pareto图,各因素对多晶条倾斜角度影响的主效应图,各因子对刻蚀效果的正态分布图,并拟合获得了多晶栅刻蚀的最优化条件。运用最优化条件刻蚀多晶栅,其结果表明剖面倾斜角度及表面形貌均能达到MOS器件的工艺制造要求。     

Ar/CHF_3反应离子束刻蚀SiO_2的研究

介绍了Ar/CHF3反应离子束刻蚀和离子束入射角对图形侧壁陡直度及刻蚀选择比的影响。使用紫外曝光技术在SiO2基片上获得光刻胶掩模图形,采用Ar CHF3来刻蚀石英基片,调节二者的流量配比,混合后通入离子源。在Ar和CHF3的流量比为1∶2,总压强为2×10-2Pa,离子束流能量为450 eV,束流为80 mA,加速电压220 V~240 V,离子束入射角15°并旋转样品台的情况下,刻蚀20 min后,得到光栅剖面倾角陡直度为80°~90°。同时发现,添加CHF3后,提高了SiO2的刻蚀速率和刻蚀SiO2与光刻胶的选择比,最高可达7∶1。     

Ar/CHF3反应离子束刻蚀SiO2的研究

介绍了Ar/CHF3反应离子束刻蚀和离子束入射角对图形侧壁陡直度及刻蚀选择比的影响.使用紫外曝光技术在SiO2基片上获得光刻胶掩模图形,采用Ar+CHF3来刻蚀石英基片,调节二者的流量配比,混合后通入离子源.在Ar和CHF3的流量比为12,总压强为2×10-2 Pa,离子束流能量为450 eV,束流为80 mA,加速电压220 V～240 V,离子束入射角15°并旋转样品台的情况下,刻蚀20 min后,得到光栅剖面倾角陡直度为80°～90°.同时发现,添加CHF3后,提高了SiO2的刻蚀速率和刻蚀SiO2与光刻胶的选择比,最高可达71.     

SOI planar photonic crystal fabrication: Etching through SiO2/Si/SiO2 layer systems using fluorocarbon plasmas

Dry plasma etching of sub-micron structures in a SiO₂/Si/SiO₂ layer system using Cr as a mask was performed in a fluorocarbon plasma. It was determined that the best anisotropy could be achieved in the most electropositive plasma. A gas composition yielding the desired SOI planar photonic crystal structures was optimized from the available process gases, Ar, He, O₂, SF₆, CF₄, c-C₄F₈, CHF₃, using DC bias data sets. Application of the c-C₄F₈/(noble gas) chemistry allowed fabrication of the desired SOI planar photonic crystal. The average etching rates for the pores and ridge waveguide regions were about 71 and 97 nm/min, respectively, while the average SiO₂/Si/SiO₂ to Cr etching selectivity for the ridge waveguide region was about 33:1 in case of the c-C₄F₈/90%Ar plasma with optimized parameters.     

二氧化硅纳米花的制备及发光特性研究

采用磁控溅射和化学气相沉积技术制备出二氧化硅纳米花。利用扫描电子显微镜(SEM),X射线光电子能谱(XPS)和傅里叶红外吸收谱(FTIR)对上述纳米结构进行结构表征。用荧光光谱仪(PL)对其光致发光特性进行了研究。结果表明在激发波长为325nm时,在394nm处出现一个发光峰,表现出良好的发光特性。     

Influence of activated polymer on the etching rate of SiO2 in CF4 + H2 plasma

The reactive ion etching (RIE) of SiO₂ in CF₄ + H₂ plasma is considered. The influence of activated polymer on the RIE rate of SiO₂ in CF₄ + H₂ plasma is determined by extrapolation of experimentally measured kinetics of the etching rate. It is found that the increased surface coverage by CF₂ radicals suppresses the RIE rate of SiO₂ in CF₄ + H₂ plasma during the initial stages of the etching process. The formation of activated polymer becomes pronounced when adsorbed CF₂ radicals are slowly activated. The activated polymer intensifies the etching reaction and enhances the etching rate. At the same time, the activated polymer intensifies the polymerization reactions. The increased surface coverage by the polymer suppresses the RIE rate of SiO₂ in CF₄ + H₂ plasma at later stages of the etching process.     

Isotropic etch for SiO2 microcantilever release with ICP system

Inductively coupled plasma (ICP) system has been widely used for anisotropic silicon etching because it offers high aspect ratio with a vertical side wall. The isotropic etching capability of the ICP system, however, has not gained much attention, even though it possesses advantages in profile control and high etching rate over wet isotropic etching or conventional RIE (reactive ion etching). We report here an isotropic dry etching process to release microcantilever beams. Investigations have covered chamber pressure, plasma source power, substrate power, SF₆ (sulfur hexafluoride) flow rate relating to Si etching rate, undercutting rate, and isotropic ratio. The SiO₂ (silicon dioxide) cantilevers were successfully released from the Si substrate and the optimized silicon etching rate was 9.1 μm per minute. The etching profiles were analyzed by scanning electron micrographs (SEM).     

High selectivity (SiN/SiO2) etching using an organic solution containing anhydrous HF

An etching process with high selectivity for SiN relative to SiO₂ at a low temperature is required for an etching process in LSI process. We achieved SiN film etching with high selectivity using an organic solvent (ethylene glycol dimethyl ether) containing anhydrous hydrogen fluoride. Selectivity as high as 15 was obtained at 80 °C. It was found that anhydrous HF effectively induces high selectivity for SiN relative to SiO₂. SiN film etching with high selectivity performed at low temperature for a single wafer process can be readily applied to future node technology devices.     

用于非易失性相变存储器中Si2Sb2Te5在CF4/Ar等离子体下的反应离子刻蚀

Phase change random access memory（PCRAM） is one of the best candidates for next generation nonvolatile memory,and phase change Si₂Sb₂Te₅ material is expected to be a promising material for PCRAM.In the fabrication of phase change random access memories,the etching process is a critical step.In this paper,the etching characteristics of Si₂Sb₂Te₅ films were studied with a CF₄/Ar gas mixture using a reactive ion etching system.We observed a monotonic decrease in etch rate with decreasing CF4 concentration,meanwhile,Ar concentration went up and smoother etched surfaces were obtained.It proves that CF4 determines the etch rate while Ar plays an important role in defining the smoothness of the etched surface and sidewall edge acuity.Compared with Ge₂Sb₂Te₅, it is found that Si₂Sb₂Te₅ has a greater etch rate.Etching characteristics of Si₂Sb₂Te₅ as a function of power and pressure were also studied.The smoothest surfaces and most vertical sidewalls were achieved using a CF₄/Ar gas mixture ratio of 10/40,a background pressure of 40 mTorr,and power of 200 W.     

基于SiO2溶胶的稳定性的Cu/SiO2催化体系在化学机械抛光中的应用研究

There is a lot ofhydroxyl on the surface ofnano SiO2 sol used as an abrasive in the chemical mechanical planarization （CMP） process, and the chemical reaction activity of the hydroxyl is very strong due to the nano effect. In addition to providing a mechanical polishing effect, SiO2 sol is also directly involved in the chemical reaction. The stability of SiO2 sol was characterized through particle size distribution, zeta potential, viscosity, surface charge and other parameters in order to ensure that the chemical reaction rate in the CMP process, and the surface state of the copper film after CMP was not affected by the SiO2 sol. Polarization curves and corrosion potential of different concentrations of SiO2 sol showed that trace SiO2 sol can effectively weaken the passivation film thickness. In other words, SiO2 sol accelerated the decomposition rate of passive film. It was confirmed that the SiO2 sol as reactant had been involved in the CMP process of copper film as reactant by the effect of trace SiO2 sol on the removal rate of copper film in the CMP process under different conditions. In the CMP process, a small amount of SiO2 sol can drastically alter the chemical reaction rate of the copper film, therefore, the possibility that Cu/SiO2 as a catalytic system catalytically accelerated the chemical reaction in the CMP process was proposed. According to the van＇t Hoff isotherm formula and the characteristics of a catalyst which only changes the chemical reaction rate without changing the total reaction standard Gibbs free energy, factors affecting the Cu/SiO2 catalytic reaction were derived from the decomposition rate of Cu （OH）2 and the pH value of the system, and then it was concluded that the CuSiO3 as intermediates of Cu/SiO2 catalytic reaction accelerated the chemical reaction rate in the CMP process. It was confirmed that the Cu/SiO2 catalytic system generated the intermediate of the catalytic reaction （CuSiO3） in the CMP process through the removal rate of copper film, infrared spectrum and AFM diagrams in different pH conditions. FinalLy it is concluded that the SiO2 sol used in the experiment possesses stable performance; in the CMP process it is directly involved in the chemical reaction by creating the intermediate of the catalytic reaction （CuSiO3） whose yield is proportional to the pH value, which accelerates the removal of copper film.