紫外压印模版的制备

概述了紫外压印的原理及其优点,并通过对紫外压印模版特殊性的分析,提出了两种紫外压印模版的制作。用反应离子刻蚀法制作了玻璃模版,用浇灌法制作了聚二甲基硅氧烷(PDMS)模版,最后给出了实验过程和结果。实验表明,用反应离子刻蚀法可以制作出具有100 nm特征尺寸、图形的深度为50 nm的玻璃模版,而且通过控制刻蚀时间可以得到需要的图形深度。用浇灌法可以制作出具有100 nm特征尺寸、图形深度为145 nm的聚合物模版。     

纳米压印技术的工艺和图形精度研究

纳米压印技术通过压印实现了纳米结构的图形转移,具有分辨率高、效率高、成本低的优点。通过对纳米压印过程中影响图形精度的一些因素进行分析,提出了相应的解决方法。结合研制的NIL-01型压印机进行工艺实验,给出纳米压印工艺实验的结果,并对结果进行了分析。试验表明：考虑到影响压印图形精度的各种因素,采用镀有Cr的SiO2模版和NIL-01型压印机,用热压印技术可以压印出具有100nm特征尺寸的PMMA图形。     

应用传统紫外光刻机进行紫外压印

基于紫外光固化的紫外纳米压印技术可在常温常压条件下实现纳米结构批量复制,具有高分辨率、高效率和低成本的优点。通过对紫外纳米压印原理和工艺的分析,制备了石英玻璃模板,实现了在商用紫外固化聚合物OG154上的紫外纳米压印,转移复制了具有100nm特征的5cm×5cm面积的纳米结构图形。同时,介绍了如何利用传统紫外光刻机的套刻对准系统进行紫外纳米压印和套刻对准的方法。     

气囊气缸式真空紫外纳米压印设备研制

本文介绍了紫外纳米压印技术原理,以及工艺中模板与基片的平行度对压印质量的影响.研制了气囊气缸式真空紫外纳米压印设备,其通过气囊气缸使模板与基片平行,从而可在大面积基片上确保压力均匀.研制了相应的光学系统,着重讨论了如何实现紫外纳米压印以及光学系统的设计和调整.制备了石英玻璃模板,实现了在商用紫外固化聚合物OG154上的紫外纳米压印,转移复制了具有100nm特征的5cm×5cm面积的纳米结构图形.     

纳米压印工艺中关键技术

纳米压印技术由于其分辨率高、工艺成本低以及适于大规模工业化生产的优点被广泛利用于纳米尺度的半导体器件的制作之中。然而,传统的硬模板压印技术存在着模板寿命短、大面积均匀性差以及易受颗粒影响的缺点。本文提出了一种高分子聚合物软模板（IPS）压印的方法来改进以上缺点,同时,本文提出在软模板制作和后续的紫外压印中采用变温变压阶梯升降压的方法来提高压印过程中胶的流动性,以提高压印图形的质量。最后,我们利用这种方法方法出了高质量的50纳米线宽的光栅图形。     

利用PDMS纳米结构薄膜增强玻璃基板出光

以纳米压印技术为基础制备了具有纳米结构的聚二甲基硅氧烷(PDMS)薄膜.将纳米结构中间聚合物模板(IPS)薄膜覆盖在有PDMS溶液的玻璃基板上,真空加热后在玻璃基板上得到PDMS网格结构薄膜.这种方式得到的网格结构形状保持较好且厚度均匀无气泡,IPS薄膜不仅可以反复使用以减少Si母版的材料损耗,还可以缩短网格结构的制备...     

新型含硅丙烯酸酯型纳米压印胶的研究与应用

纳米压印技术因其成本低、产量高的优点广受关注,而开发可适用于纳米压印的压印胶成为该工艺的关键。合成了一种硅含量高的单体三(三甲基硅氧基)甲基丙烯酰氧丙基硅烷(TRIS),制备了一种新型紫外纳米压印用含硅丙烯酸酯型压印胶,用四点弯曲实验机和接触角测试仪表征了压印胶与模板的黏附性能,研究了配方组成对模板黏附性能的影响,优化得到了抗黏附性能优异的配方。压印实验结果表明,该压印胶与模板分离时无粘连。AFM与SEM测试结果表明,压印胶上复制得到了线宽149 nm、周期298 nm、深宽比为1的纳米光栅图形,图形结构完整。     

基于OG154的紫外纳米压印研究

制作出适用于紫外压印的模板,用自行研制的UVNIL-01型气囊气缸式紫外压印机,分别在硬质纸板上和石英玻璃上做了紫外压印实验。用紫外固化聚合物OG154完成了紫外纳米压印,转移复制了具有100nm特征尺寸纳米结构图形。在实验中,采用的模板面积为5cm×5cm,压力最大为2bar,脆性模板和基片未发生破裂,表明气囊气缸压印系统可以完成大面积图形的转印。实验结果表明,硬质纸板对聚合物OG154的粘附力大于模板对聚合物的粘附力,很利于脱模分离。石英玻璃基板对OG154的粘附力小,很容易剥离成OG154薄膜。     

纳米器件的一种新制造工艺——纳米压印术

纳米压印术可以用于大批量重复性地制备纳米图形结构。此项技术具有操作简单、分辨率高、重复性好、费时少,成本费用极低等优点。本文介绍了较早出现的软刻印术的两种方法———微接触印刷法和毛细管微模制法。详细讲述了纳米压印术(主要指热压雕版压印法)的各步工序———压模制备、压印过程和图形转移,以及用于压印的设备、纳米图案所达到的精确度等,还简述了纳米压印术的另一方法———步进-闪光压印法。最后,通过范例介绍了纳米压印术在制作电子器件、CD存储器和磁存储器、光电器件和光学器件、生物芯片和微流体器件等方面的应用。     

一种新型聚合物微透镜阵列的制造技术

提出了一种利用软模压印制备微透镜阵列的技术.采用传统的光刻胶热熔方法制备微透镜阵列母板,利用复制模具的方法在聚二甲基硅氧烷(PDMS)上得到一个和母板表面图形相反的模具,最后通过压印的方法把PDMS模具上的图形转移到涂有紫外固化胶的玻璃基片上,待紫外胶完全固化后可得到和母板一致的微透镜阵列.经过测试微透镜阵列的焦点图像和表面形貌可发现最后制备的微透镜阵列表面形貌均匀、聚焦性能良好、光忖强均匀.     

Nanoholes by soft UV nanoimprint lithography applied to study of membrane proteins

In this paper, we present an alternative technique to the well-known electron beam lithography in order to realize nanoholes in the silicon substrates for biological applications. The used technique is soft UV nanoimprint lithography (UV-NIL). We optimized the fabrication of silicon based supports obtained by soft UV-NIL and reactive ion etching to carry out very large arrays of nanoholes. The resolution limits are investigated when using poly(dimethylsiloxane) as flexible mold material. RIE conditions are initiated to limit the lateral mask resist etch.     

Technique for transfer of high-density,high-aspect-ratio nanoscale patterns in UV nanoimprint lithography and measurement of the release force

Ultraviolet nanoimprint lithography (UV-NIL) is a powerful tool for nanoscale fabrication. However, the replication of high-density, high-aspect-ratio mold patterns by UV-NIL is very difficult because of the strong forces required to release the replicate from the mold. We used a glassy carbon (GC) mold with an antireflective structure, fabricated by irradiation with an oxygen-ion beam, to produce a high-density, high-aspect-ratio pattern, and we evaluated its release properties. The fabricated GC surface contained high-aspect-ratio conical structures with pitch of less than 100 nm. After fabrication of the antireflective structure, the mold surface was coated with chromium and a fluorinated silane coupling agent. By using this treatment and a peel motion during mold release, faithful replication of the mold structure in photocurable resin was possible. The release force increased with increasing mold surface area; the surface area effect is therefore the main factor in the mold-release step.     

Soft-lithographic methods for the fabrication of dielectrophoretic devices using molds by proton beam writing

Proton beam writing (PBW) was applied to the fabrication of dielectrophoretic (DEP) devices equipped with high-aspect-ratio pillar arrays. With coupled use of soft lithography for micro-fluidic channels, we successfully fabricated a device equipped with SU-8 pillar arrays produced by PBW, which is covered with a poly-dimethylsiloxane (PDMS) micro-fluidic channel. For more simplified prototyping of the device, we modified a SU-8 mold for simultaneous replication of both pillar arrays and micro-fluidic channel on PDMS. Replication of pillar arrays is limited to the aspect ratio of less than three.     

Soft UV-NIL at 20 nm scale using flexible bi-layer stamp casted on HSQ master mold

In this paper we present a comparative study of two e-Beam Lithography (EBL) processes for Nanoimprinting Lithography (NIL) master mold, i.e. the standard PMMA based EBL Si patterning process and the HSQ process. 20 nm features with minimal sidewall roughness and high uniformity are demonstrated on large surface by using HSQ process. Moreover, to validate this ultra-high resolution HSQ EBL process and to check NIL resolution performances, soft UV-NIL replications were performed using soft hard-PDMS/PDMS bi-layer stamps casted on the HSQ master mold. We demonstrate the replication of sub-20 nm nanodots of high density (pitch 60 nm) with a good uniformity on the whole field area.     

Direct soft UV-NIL with resist incorporating carbon nanotubes

As a potential candidate for the next generation of nanolithography, nanoimprint lithography (NIL) has drawn ever-increasing worldwide attention. It involves physical contact to overcome the optical limits occurring in sub-100 nm photolithography. Affordable tool cost is one of major attractive points of NIL. This work proposes the idea of incorporating carbon nanotubes (CNTs) in the resin used for ultraviolet nanoimprinting (UV-NIL). CNTs can make the resin electrically conductive when mixed with it. Patterns imprinted in the CNT-mixed resist can then be used to replace conductive metal structures directly. This enhances the productivity of basic UV-NIL where the imprinted patterns are used as sacrificial etch masks. In this work, several types of CNTs were purified chemically and dispersed before being mixed with UV-NIL resin using ultrasonic vibration. On drops of CNT-mixed resin, soft UV-NIL was performed using a polydimethylsiloxane (PDMS) stamp with a minimum feature size in the range of 200 nm. Even with increased resin viscosity due to the addition of CNTs, UV imprinting down to 200 nm was successfully done with moderate pattern fidelity. The loading rate of nanotubes should be minimized to prevent the increased viscosity from degrading the pattern transfer resolution. The electrical conductivity of CNT-mixed resist increases with the loading of CNTs. Therefore, the trade-off between the electrical properties and pattern transfer resolution needs to be optimized carefully.     

Direct fabricating patterns using stamping transfer process with PDMS mold of hydrophobic nanostructures on surface of micro-cavity

The transfer stamping process has been used to fabricate thin-film pattern in recent years. Due to the characteristics of the materials of molds and inks, residual inks on the cavities of mold and residual layers on the substrate are still a problem. To solve the problem, we present a concept for fabrication of hydrophobic nanostructures on the cavities of microstructures of the mold, which can effectively decrease the ink residing on the cavities of the mold during coating. First, the periodic nanopores are fabricated on the anodic aluminum oxide (AAO). Second, AAO membrane is employed as the template for fabricating nanostructures on the PC film by embossing. And then, by partial protrusion of the nano-structured PC film into the micro-holes of the mold, an array of protruded convex microstructures is formed. After that, polydimethylsiloxane (PDMS) mold is casted from the embossed PC film. The contact angle of nanostructures on the micro-cavities of PDMS mold is about 145°. Micro-patterns with no residual layers have been successfully transferred on the poly(ethylene terephthalate) (PET) substrate using a transfer stamping process with this PDMS mold.     

Fabrication and characterization of Co-Pt nanodot arrays by nanoimprint lithography and electrodeposition

Co-Pt nanodot arrays of 50 nm in diameter and 100 nm pitch were fabricated by nanoimprint lithography and electrodeposition process. A polymer mold used was replicated from a Si master mold with nanopatterns which were fabricated by EBL and ICP-RIE, where hydrophobic surface of these was achieved by FOTS coating. UV-NIL was successfully performed under pressures of 5 MPa for 5 min with an UV exposure time of 30 s, where the substrate was Ru (30 nm)/NiFe (10 nm)/Ta (5 nm)/Si (1 0 0). The size of patterns was measured at 53 nm in diameter, 25 nm in height, 100 nm in pitch. Finally, Co-Pt nanodot arrays were galvanostatically electrodeposited and characterized. The size and the composition of these arrays were measured to be 50 nm in diameter and 100 nm in pitch and Co-23.6 at.% Pt, respectively. According to MFM analysis, these arrays for the remnant states represent a single domain structure of perpendicular direction with a magnetic field, where a field of 15 kOe was applied perpendicular to the sample plane. These results show that for the Co-Pt dot arrays of 50 nm diameter perpendicular magnetic signal can be recorded and switched.     

一种聚合物实心微针的制作方法

为实现制作微针加工工艺简单、加工周期短及成本低的目的,提出了一种制作聚合物微针的新方法,这种聚合物微针的制作过程主要包括三个部分:微针原始模具的制作、聚合物微针模具的制作和浇铸工艺复制微针。通过KOH腐蚀液刻蚀晶面为{100}的Si片和紫外线对准光刻SU8胶得到由Si-SU8胶构成的原始模具,再在该模具上注入聚二甲基硅氧烷(PDMS)进行转模,固化脱模后在PDMS微针二级模具表面溅射一层Cu/Cr金属薄膜,然后再注入PDMS,得到最终的聚合物微针模具,对该模具进行浇铸工艺,便可批量制作微针。通过浇注PDMS获得微针初始结构,使针尖和针体合为一体,提高了脱模的可靠性;通过改变设计,能得到不同截面尺寸和长度的微针,因此这种方法具有很高的灵活性。     

Anodized Aluminum Oxide/Polydimethylsiloxane Hybrid Mold for Roll‐to‐Roll Nanoimprinting

Two types (hard and soft) of the molds are widely used in nanoimprint lithography for a high throughput over a large area, and high‐resolution parallel patterning. Although hard molds have proven excellent resolutions and can be used at high temperatures, cracks often occur in the mold in addition to the requirement of high imprinting pressure. On the other hand, though soft molds can operate at lower pressures, they give poor pattern resolution. Here, a novel hybrid mold of anodized aluminum oxide (AAO) template attached to a flexible polydimethylsiloxane (PDMS) plate is introduced. Due to the flexible nature of PDMS, various polymer nanostructures are obtained on flat and curved substrates without crack formation on the AAO mold surface. Furthermore, the hybrid mold is successfully used for roll‐to‐roll imprinting for the fabrication of high density array of various shaped polymeric nanostructures over a large area.     

UV nanoimprint lithography of sub-100 nm nanostructures using a novel UV curable epoxy siloxane polymer

We reported the replication of sub-100 nm nanostructures by an ultraviolet (UV) nanoimprint lithography (NIL) technique. We used a novel UV curable epoxy siloxane polymer as the NIL resist to achieve features as small as 50 nm. The polymeric soft molds for the NIL were fabricated by casting toluene diluted poly(dimethyl-siloxane) (PDMS) on the hydrogensilsesquioxane (HSQ) hard mold. The NIL results were characterized by using a scanning electron microscope and an atomic force microscope. Our results illustrate that, with the epoxy siloxane resist, the 50 nm HSQ features on the hard mold can be successfully replicated using PDMS soft molds.