Multicomponent Physical Vapor Deposited Films with Homogeneous Molecular Material Distribution Featuring Improved Resist Sensitivity

Each film preparation technique affects the physical properties of the resulting coating and thus defines its applicability in modern device construction. In this context solvent based spin coated and solvent‐free physical vapor deposited molecular glass photoresist films are systematically investigated for their dissolution behavior, sensitivity, and overall lithographic performance. These investigations demonstrate that the solvent‐free physical vapor deposition leads to a marked increase in sensitivity. This could be explained by the individual molecule by molecule deposition step producing a more homogeneous distribution of the multicomponent resist system, especially the photoacid generator. In addition, this assumption is supported by former published simulations focusing on aggregate formation within thin films. This work demonstrates that the lithographic sensitivity of multicomponent resist system is an intrinsic parameter to investigate molecular material distribution and indicates that the applied film preparation technique is crucial for the corresponding performance and applicability.     

电子束抗蚀剂图形结构的倒塌与粘连

首先从实验现象出发,阐述了纳米级高密度、高深宽比电子抗蚀剂图形结构发生倒塌与粘连的主要几何因素及其关系。除了结构的几何因素外,结合"Beam Sway"模型分析了抗蚀剂微细结构在制作过程中的受力情况。在上述工作的基础上,提出了克服纳米级高密度、高深宽比电子抗蚀剂图形结构倒塌与粘连的相应措施。其中,通过实验验证了超临界CO2干燥技术对于电子束抗蚀剂ZEP520A用于制作周期200nm及150nm、深宽比超过4的光栅图形结构具有良好的效果。     

Fullerene Resist Materials for the 32 nm Node and Beyond

Current resist materials cannot simultaneously meet the sensitivity, resolution and line width roughness (LWR) requirements set out by the International Technology Roadmap for Semiconductors (ITRS) for the 32nm node and beyond. Here we present a fullerene‐based, chemically amplified resist system, which demonstrates the potential to fulfill these requirements for next generation lithography. A chemically amplified fullerene resist was prepared, consisting of the derivative MF07‐01, an epoxide crosslinker, and a photoacid generator, such as triarylsulfonium hexafluoroantimonate. The sensitivity of this resist was shown to be between 5 and 10 µC cm^?2 at 20 keV for various combinations of post‐application bake and post‐exposure bake conditions. Using 30 keV electron beam exposure, sparse patterns with 15 nm resolution were demonstrated, whilst for dense patterns a half‐pitch of 25 nm could be achieved. The LWR for the densely patterned features is ～4 nm. The etch durability of the fullerene CA system was shown to be comparable to that of SAL601, a common novolac‐based commercial resist, at almost four times that of silicon.     

用三层胶工艺X射线光刻制作T型栅

采用三层胶工艺X射线光刻制作T型栅,一次曝光,分步显影,基本解决了不同胶层间互融的问题.该方法制作效率高,所制作的T型栅形貌好,头脚比例可控,基本满足器件制作要求.     

LB技术制备大面积超薄PMMA抗蚀层的研究

采用自行研制的ＬＢ自动提膜装置，制备出大面积（１０×８ｃｍ２）、高质量的ＰＭＭＡ超薄抗蚀剂膜，并将其用于高分辨率铬掩模版的研制。通过电子束曝光，湿法蚀刻，制作了分辨率优于０．５μｍ，特征线宽０．３８μｍ的４（１００ｍｍ）铬掩模版。     

电子束三维光刻技术的研究

在IH(Integrated Harden Polymer Stereo Lithography)技术和电子束光刻技术的基础上提出了电子束微三维光刻技术新概念。对其实现方法的可行性进行了简要的理论分析，并使用SDV—Ⅱ型真空腔在约1．33Pa的真空下对环氧618、WSJ-202和苏州2号抗蚀剂进行了气化试验，得出了它们在真空中的气化实验结果，证明了电子束液态光刻的可行性。     

Boehmite filled hybrid sol-gel system as directly writable hard etching mask for pattern transfer

We discuss some preliminary results on the development of a new kind of positive tone resist whose peculiarity is an extreme dry etch resistance. This profitable property is obtained by loading and compatibilizing with ceramic nano particles a radiation sensitive sol-gel silica based hybrid organic/inorganic system. With an appropriate choice of the nano particles, the investigated approach is suitable to be adapted and optimized for achieving high selectivity in plasma etching processes of different materials. Here, we specifically demonstrate how the filling with boehmite nano particles (aluminum hydroxide, y-AlO(OH)) confers a much higher selectivity (>60) to the radiation sensitive silica based system when used for the etching of silicon, that show a selectivity <2 if unloaded. The patterning of the new resist was carried out by X-ray lithography while the dry etching tests were made with a fluorine-based chemistry.     

Novel Patterning of Gold Using Spin‐Coatable Gold Electron‐Beam Resist

Conventional lithography methods of gold patterning are based on deposition and lift‐off or deposition and etching. In this letter, we demonstrate a novel method of gold patterning using spin‐coatable gold electron‐beam resist which is functionalized gold nanocrystals with amine ligands. Amine‐stabilized gold electron beam resist exhibits good sensitivity, 3.0 mC/cm², compared to that of thiol‐stabilized gold electron beam resists. The proposed method reduces the number of processing steps and provides greater freedom in the patterning of complex nanostructures.     

Calibration algorithms for an electron beam metrology system

This paper discusses the general deflection system calibration problem that occurs in electron beam lithography and metrology systems.These systems generally have an X, Y stage whose position can be measured, but not set to a high degree of accuracy.The calibration problem involves aligning the coordinate system associated with electron beam deflection system to that of the X, Y stage, and measuring the deflection system sensitivity.Current commercially available examples of these systems include the Cambridge Instruments EBMF-6 electron beam lithography system and the EBMT-5 electron beam metrology system.     

紫外纳米压印用PMMA转移层膜的制备及性能

以苯甲醚为溶剂,采用旋涂法制备PMMA(聚甲基丙烯酸甲酯)转移层膜。当PMMA的质量分数为5%、旋涂速度为2000～6000r/min时,转移层膜的厚度为90～150nm,粗糙度为0.3nm,可满足纳米压印要求。采用接触角测量仪测试计算出PMMA、PS转移层膜的表面能,并通过转移层膜与压印胶之间的粘附功和界面张力的计算,评价了PMMA、PS和Si片对压印胶的润湿和粘附性能。结果表明,PMMA膜可改善压印胶在基片上的润湿铺展性能和粘附性能,而PS膜虽能改善基片的润湿铺展性能,却不利于压印胶的粘附。     

3D Out‐of‐Plane Rotational Etching with Pinned Catalysts in Metal‐Assisted Chemical Etching of Silicon

Pinned structures in conjunction with shaped catalysts are used in metal‐assisted chemical etching (MACE) of silicon to induce out‐of‐plane rotational etching. Sub‐micro‐ and nanostructures are fabricated in silicon, which include scooped‐out channels and curved subsurface horns, along with vertically oriented thin metal structures. Five different etching modes induced by catalyst and pinning geometry are identified: 1) fully pinned–no etching, 2) rotation via twist, 3) rotation via delamination, 4) in‐plane bending, and 5) swinging. The rotation angle is roughly controlled through catalyst geometry. The force and pressure experienced by the catalyst are calculated from the deformation of the catalyst and range between 0.5–3.5 μN and 0.5–3.9 MPa, respectively. This is a new, simple method to fabricate 3D, heterogeneous sub‐micro‐ and nanostructures in silicon with high feature fidelity on the order of tens of nanometers while providing a method to measure the forces responsible for catalyst motion during MACE.     

A method to restrain the charging effect on an insulating substrate in high energy electron beam lithography

Pattern distortions caused by the charging effect should be reduced while using the electron beam lithography process on an insulating substrate. We have developed a novel process by using the SX AR-PC 5000/90.1solution as a spin-coated conductive layer, to help to fabricate nanoscale patterns of poly-methyl-methacrylate polymer resist on glass for phased array device application. This method can restrain the influence of the charging effect on the insulating substrate effectively. Experimental results show that the novel process can solve the problems of the distortion of resist patterns and electron beam main field stitching error, thus ensuring the accuracy of the stitching and overlay of the electron beam lithography system. The main characteristic of the novel process is that it is compatible to the multi-layer semiconductor process inside a clean room, and is a green process, quite simple, fast, and low cost. It can also provide a broad scope in the device development on insulating the substrate,such as high density biochips, flexible electronics and liquid crystal display screens.     

纳米尺度多晶硅微结构刻蚀研究

以HBr作为刻蚀气体,采用ICP金属刻蚀系统对气体流量、刻蚀压力、离子源功率、偏压功率等工艺参数与刻蚀速率、刻蚀选择比和侧壁垂直度的对应关系进行了大量工艺实验。借助理论分析和工艺条件的优化,开发出一套可满足制备侧壁垂直度的纳米尺度多晶硅密排线结构的优化刻蚀工艺技术。实验结果表明:当采用900 W的离子源功率、11 W的偏压功率、25 cm3/min流量的HBr气体和3 mTorr(1 mTorr=0.133 3 Pa)刻蚀压力的工艺条件时,多晶硅与二氧化硅的刻蚀选择比大于100∶1;在保持离子源功率、偏压功率、气体流量不变的条件下,单纯提高反应腔工艺压力则会大幅提高上述选择比值,同时损失多晶硅和二氧化硅的刻蚀均匀性;HBr气体流量的变化在上述功率及反应腔工艺压力的工艺范围内,对多晶硅与二氧化硅的刻蚀选择比和多晶硅刻蚀的形貌特征均无显著影响。采用上述优化的刻蚀工艺条件,配合纳米电子束光刻技术成功得到多晶硅纳米尺度微结构,其最小线宽为40 nm。     

Growth and Properties of Hybrid Organic‐Inorganic Metalcone Films Using Molecular Layer Deposition Techniques

Molecular layer deposition (MLD) is a useful technique for fabricating hybrid organic‐inorganic thin films. MLD allows for the growth of ultrathin and conformal films using sequential, self‐limiting reactions. This article focuses on the MLD of hybrid organic‐inorganic films grown using metal precursors and various organic alcohols that yield metal alkoxide films. This family of metal alkoxides can be described as “metalcones”. Many metalcones are possible, such as the “alucones” and “zincones” based on the reaction of trimethylaluminum and diethylzinc, respectively, with various organic diols such as ethylene glycol. Alloys of the various metalcones with their parent metal oxide atomic layer deposition (ALD) films can also be fabricated that have an organic‐inorganic composition that can be adjusted by controlling the relative number of ALD and MLD cycles. These metalcone alloys have tunable chemical, optical, mechanical, and electrical properties that may be useful for designing various functional films. The metalcone hybrid organic‐inorganic materials offer a new tool set for engineering thin film properties.     

表面活性剂在IC芯片光刻工艺中的应用

叙述了表面活性剂的性质、分类、分子结构特点,重点介绍了表面活性剂在光刻工艺的涂胶、显影、湿刻工序中的应用.适当加入表面活性剂,在现有设备的条件下可极大地提高光刻质量,对双极电路以及CMOS电路制作都有着重要的现实意义.     

铁电刻蚀的研究进展

铁电刻蚀是一种新颖的刻蚀技术,在铁电研究领域日益受到重视。对铁电刻蚀的研究现状进行了综述。首先介绍了铁电极化对铁电材料表面性能的影响,然后详细阐述了铁电畴图形化的三种方法,即微电极图形化、扫描探针图形化和电子束图形化,并分析了它们的图形化机制和特点。其中微电极方法的铁电畴图形的最小尺寸为微米量级,而扫描探针和电子束方法的铁电畴图形的最小尺寸可小于100nm。与铁电畴定位的表面反应相结合,铁电刻蚀可为纳米结构的制造提供新的途径,因此在纳米器件领域具有广泛的应用前景。未来铁电刻蚀技术发展的方向是在改进铁电刻蚀技术的同时推进其在纳米器件制造中的应用。     

Atomic and Molecular Layer Deposition of Hybrid Mo–Thiolate Thin Films with Enhanced Catalytic Activity

A synthetic route toward hybrid MoS₂‐based materials that combines the 2D bonding of MoS₂ with 3D networking of aliphatic carbon chains is devised, leading to a film with enhanced electrocatalytic activity. The hybrid inorganic–organic thin films are synthesized by combining atomic layer deposition (ALD) with molecular layer deposition (MLD) using the precursors molybdenum hexacarbonyl and 1,2‐ethanedithiol and characterized by in situ Fourier transform infrared spectroscopy, and the resultant material properties are probed by X‐ray photoelectron spectroscopy, Raman spectroscopy, and grazing incidence X‐ray diffraction. The process exhibits a growth rate of 1.3 Å per cycle, with an ALD/MLD temperature window of 155–175 °C. The hybrid films are moderately stable for about a week in ambient conditions, smooth (σ_RMS ≈ 5 Å for films 60 Å thick) and uniform, with densities ranging from 2.2–2.5 g cm^?3. The material is both optically transparent and catalytically active for the hydrogen evolution reaction (HER), with an overpotential (294 mV at ?10 mA cm^?2) superior to that of planar MoS₂. The enhancement in catalytic activity is attributed to the incorporation of organic chains into MoS₂, which induces a morphological change during electrochemical testing that increases surface area and yields high activity HER catalysts without the need for deliberate nanostructuring.     

8通道-1.6nm Si纳米线阵列波导光栅的设计与制作

设计了基于绝缘层上硅(SOI)材料的8通道Si纳米线阵列波导光栅(AWG),器件的通道间隔为1.6nm,面积为420μm×130μm。利用传输函数法模拟了器件传输谱,结果表明,器件的通道间隔为1.6nm,通道间串扰为17dB。给出了结合电子束光刻(EBL)和感应耦合等离子(ICP)刻蚀技术制备器件的详细流程。光谱测试结果分析表明,器件通道间隔为1.3～1.6nm,通道串扰为3dB,中心通道损耗为11.6dB。