TFT光刻平面倾斜对光刻图形的影响及改善

薄膜晶体管光刻制程中,光刻胶光刻平面位置是决定光刻图形质量的关键因素。为了在光刻机最小分辨率条件下改善光刻图形质量,本文从光刻胶内反射光线的反射特点出发,以减小光刻胶内反射光线对非光刻区域的光刻光强及增加光刻区域的光刻胶底部光刻光强为基础,推导出光刻光线倾斜入射光刻胶平面时,光刻胶光刻平面位置调整量的计算公式,并以该公式计算出的调整量对光刻胶光刻平面进行调整。结果表明：对于最小分辨率为3.0 μm的投影光刻机,进行线间距为2.2 μm的产品光刻时,以该公式计算出的调整量对光刻胶光刻平面调整后,较未调整前,光刻图形坡度角提升了13.3%,光刻胶线宽或线间距宽度(DICD)均一性改善了14.7%,光刻图形光刻胶残留得到解决。     

采用双向偏置曝光的成像干涉光刻技术

成像干涉光刻技术(IIL)具有干涉光刻技术(IL)的高分辨力和光学光刻技术(OL)产生任意形状集成电路特征图形的能力。在IIL中,按掩模图形的不同空间频率成份分区曝光,并使其在抗蚀剂基片上非相干叠加,得到高分辨抗蚀剂图形。本文在研究一般三次曝光IIL原理基础上,提出采用沿X轴正、负方向以及沿Y轴正、负方向偏置的双向偏置照明,分别曝光 X方向、-X方向、 Y方向、-Y方向的高空间频率分量并与垂直于掩模方向的低空间频率分量曝光相结合的五次曝光IIL。理论和计算模拟表明,该方法可以提高图形对比度和分辨力,并减小因调焦误差引起的图形横向位移误差,有利于改善抗蚀剂图形质量。     

相移掩模和光学邻近效应校正光刻技术

详细地论述了相移掩模提高光刻分辨力和改善焦深的原理。介绍了光学邻近效应校正方法、改善光刻图形质量的机理及邻近效应校正掩模的一些设计问题。     

用多光束干涉实现纳米级阵列图形的长焦深光刻

用多束相干光适当组合干涉曝光,得到的图形与基片在干涉场内的纵向位置z无关,与x、y位置呈周期关系,光的相干长度对应传统光学光刻的焦深。该方法适合大尺寸基片上纳米级孔、锥阵列图形的制作。模拟了双光束双曝光、三光束单曝光和四光束单曝光的干涉场光强分布,用波长为441.6nm的激光曝光得到尺寸为200nm的孔阵和点阵的图形。     

数字光刻缩微投影系统物镜的设计

针对高精度数字光刻的缩微光学投影系统,提出并设计了一种适用于0.7XGA型数字微反射镜(DMD)的6片式数字光刻缩微投影物镜。通过优化和拼接三片式物镜结构,得到数值孔径NA=0.1,放大倍率为-0.2558,分辨力达3.5μm,不受DMD栅格效应影响且达到衍射极限的缩微物镜。经过Zemax软件模拟得到其全视场光程差小于λ/5,145cycles/mm处的调制传递函数(MTF)大于0.58,充分说明该缩微物镜已经达到光刻物镜设计要求。利用Monte Carlo分析方法,模拟加工装配了100组镜头,设定空间频率为145cycles/mm时,90%的镜头FMTF>0.55,验证了加工装配实际可行。     

纳米光刻加工技术的研究与应用

纳米技术是一种在0.1-100nm尺度上研究原子、分子现象及其结构信息的技术。纳米技术的主要作用体现在两个方面:①促进器件小型化,使低成本、高集成度的微器件、微传感器、微型仪器成为可能;②物质在纳米尺度上表现出纳米效应,包括量子效应、较强的表面、界面效应等,会使得物质具有很多新特性,从而能够制造出新的具有特定功能的装置。纳米技术的最终目标是操纵单个原子和分子,并在纳米尺度上设计制备表面结构,进而制造出具有特定功能的产品,实现生产方式的飞跃。主要综述当前几种主要纳米光刻加工技术的类型、工艺、特点,及其在表面纳米结构加工中的应用。     

紫外线(UV)固化技术在数字成像材料中的应用(四)UV固化技术在立体光刻中的应用

近年来，数字成像技术不断提高和应用范围的迅速推广，也推动了UV固化技术在这一领域的融合和应用，取得了极大的成效，由于UV固化材料具有快速固化、高效、低污染、节能、优质等特点，很快发展成为一种新型的数字成像材料，目前已实现产业化的主要有UV喷墨打印、计算机直接制版CTP、印刷电路版数字化制作、立体光刻等四种技术，作者拟分为四个专题予以阐述，本文主要讨论其第四个专题：UV固化技术在立体光刻中的应用。     

用于100nm节点ArF准分子激光光刻的相移掩模技术

用于100nm节点ArF准分子激光光刻的相移掩模(PSM)技术主要有无铬相移掩模(CPM),交替相移掩模(APSM)、衰减相移掩模(AttPSM)和混合相移掩模技术。对这些掩模的基本原理、制作方法及性能比较进行了分析研究。研究表明,无铬相位光刻(CPL)PSM和高透AttPSM 相结合构成的混合掩模最适合用于193nmArF光刻,以产生100nm节点抗蚀剂图形。     

小型微纳米图形电子束曝光制作系统(英文)

为了满足科学实验过程中对制作半导体器件和微纳米结构的需要,同时避免受到昂贵的工业级电子束曝光(electron beam lithography,EBL)机的条件制约,构建了一种基于普通扫描电子显微镜(scanning electron microsco-py,SEM)的桌面级小型电子束曝光系统.建立了以浮点DSP为控制核心的高速图形发生器硬件系统.利用线性计算方法实现了电子束曝光场的增益、旋转和位移的校正算法.在本曝光系统中应用了新型压电陶瓷电机驱动的精密位移台来实现纳米级定位.利用此位移台所具有的纳米定位能力,采用标记追逐法实现了电子束曝光场尺寸和形状的校准.电子束曝光实验结果表明,场拼接及套刻精度误差小于100 nm.为了测试曝光分辨率,在PMMA抗蚀剂上完成了宽度为30 nm的密集线条曝光实验.利用此系统,在负胶SU8和双层PMMA胶表面进行了曝光实验;并通过电子束拼接和套刻工艺实现了氮化物相变存储器微电极的电子束曝光工艺.     

Improving drivers’ knowledge of road rules using digital games

Although a proficient knowledge of the road rules is important to safe driving, many drivers do not retain the knowledge acquired after they have obtained their licenses. Hence, more innovative and appealing methods are needed to improve drivers’ knowledge of the road rules. This study examines the effect of game based learning on drivers’ knowledge acquisition and retention. We find that playing an entertaining game that is designed to impart knowledge of the road rules not only improves players’ knowledge but also helps them retain such knowledge. Hence, learning by gaming appears to be a promising learning approach for driver education.     

An experimental investigation on the FPZ properties in concrete using digital image correlation technique

This paper presents an experimental investigation on the properties of the fracture process zone (FPZ) in concrete using the digital image correlation (DIC) technique. Based on the experimental results, it is found that the FPZ length increases during crack propagation but decreases after the FPZ is fully developed. The FPZ length at the peak load and the maximum FPZ length increase with an increase in specimen height, but decrease by increasing the notch depth to specimen height ratio. It is also found that the crack extension length at the peak load is about 0.25 times the ligament length.     

Uneven intensity change correction of speckle images using morphological Top-Hat transform in digital image correlation

By comparing two digital speckle images recorded before and after deformation, two-dimensional digital image correlation (DIC) method can accurately determine the in-plane displacement fields and strain fields. In a practical measurement, however, the variance of light source intensity, location and direction will cause the random uneven intensity change of the random speckle images and will lead to the obvious measurement error. Numerical simulation experiment is first carried out to analyse the influence of the recorded speckle images undergoing uneven light variation on DIC measurement accuracy. Then, a correction method for speckle images with uneven intensity change is proposed based on morphological Top-Hat transform. In addition, quantitative measurements of both in-plane rotation of a rigid body and three-point bending beam are investigated experimentally by DIC to verify the feasibility of the correction method. Experimental results show that the measurement accuracy of DIC is improved dramatically after the procedure of uneven light variation correction.     

An improved technique for the solution of edge crack problem for finite plate

This paper provides a detailed examination for the edge crack problem of finite plate. The Williams expansion for the crack problem is used first. Secondly, the complex potentials for the central crack problem are used in the present study, which is called the improved technique hereafter. In both techniques, the eigenfunction expansion variational method (EEVM) is used for evaluating the undetermined coefficients in the expansion form. The ratio of height versus width of plate (h/w) is varying from 1.5, 1.0, 0.75, 0.5, 0.4, 0.3 to 0.25. The ratio of edge crack length versus width of plate (a/w) takes two sets: (1) a/w = 0.1, 0.2, … to 0.9, (2) a/w = 0.01, 0.02, … to 0.09. The detailed computation proves that for moderate cases of the a/w ratio, for example, 0.2 < a/w < 08, the deviations for SIFs and T-stress from two techniques are minor. However, for the case of short edge crack length, for example, a/w < 0.05, the deviations for SIFs and T-stress from two techniques are significant. It is found that the Williams expansion may not be suitable for the short edge crack, for example, a/w < 0.05.     

The impact of digital transformation and digital marketing on the brand promotion,positioning and electronic business in Montenegro

The paper assesses the ways in which digital transformation in Montenegro influences the use of digital marketing in business, determining the impact of this concept on promotion and brand positioning, i.e. electronic business development through electronic services. This facilitates the integrated analysis of the context of electronic business, thus providing innovative and value-creating insights for Montenegro – a transition country. This research was conducted using a survey on a stratified random sample and the data was subsequently analyzed using the Structural Equation Model (SEM), Analysis of Variance (ANOVA) test, and eta-coefficient. Multivariate analysis was applied to data obtained from 172 companies. The results showed that a number of factors determine the ways in which companies apply digital marketing and use differing levels of influence, amongst which the period of implementation, the abilities of people in charge for its usage, perception of digital marketing cost-effectiveness, measurability of its effects and sufficiency of traditional marketing have a key role. The period in which digital marketing is used was especially significant and notably affects the choice of digital marketing instruments, the way its performances are measured and the managers’ perception of its cost-effectiveness. Social networks were the most commonly used form of digital marketing in the market under analysis, and Google analytics was the most common way to measure the effects of digital marketing. Furthermore, the results showed that the more a company relies on the use of digital marketing in its business, the more significant its impact on promotion and brand positioning.     

On the correction of plasticity effect at the hole edge when using the centre hole method for measuring high welding residual stress

Significant error caused by plasticity at the hole edge may arise when measuring sufficiently high welding residual stress by means of the hole drilling method. According to elastoplastic theory, a critical parameter of plastic deformation round the centre hole is obtained. On the basis of this critical parameter, a simple method is proposed to correct the stresses for the plasticity effect. It is shown in the experiments with welded joints that the correction method may improve the accuracy of high residual stress measurement.     

Design of adaptive digital filters for phase extraction in complex fringe patterns obtained using the Ronchi test

A powerful technique is presented for processing complex fringe patterns with high noise levels and arbitrary distributions of spatial frequencies, which can successfully extract the phase information. Artifacts that arise from phase extraction in local filtering approaches are avoided by using a simple design and implementation strategy for the adaptive filter, based on the theory of digital filter design used in electronics, and applied to pixel rows (or columns) in the fringe-pattern. The filter designed in this manner is then applied to phase extraction in an experimental fringe pattern measured in a digital Ronchi test setup using a Carré phase-shifting procedure. The filtering strategy has a very low computational cost and allows phase extraction in noisy ronchigrams regardless their spatial frequency distribution, provided the fringes are still visible.     

Real-time recognition of control chart patterns in autocorrelated processes using a learning vector quantization network-based approach

Researchers have been investigating the use of artificial neural networks (NNs) in the application of control chart pattern (CCP) recognition with encouraging results in recent years. Most of the NN models in this field are designed to be used in uncorrelated processes where the process data are independent. Unfortunately, the prerequisite of data independence is not even approximately satisfied in many manufacturing processes. To the best of the author's knowledge, no research results have been published to date on the application of NNs for CCP recognition in autocorrelated processes. This work first shows that autocorrelation in process data greatly affects the performance of NN-based CCP recognizers developed with independent data and then presents a learning vector quantization network-based system that can effectively recognize CCPs in real-time for processes with various levels of autocorrelation. The system performance is evaluated in terms of the classification rate and the average run length. An empirical comparison using simulation indicates that the proposed learning-based system performs better than the traditional control chart methods in detecting shifts when the process data are positively correlated, while it also offers pattern classification. A demonstration example is provided using real data.     

CCD技术研究银盐制版材料中的物理显影过程

本文利用CCD技术研究了银盐扩散转移体系的物理显影过程。原位地监测了印刷用银盐直接制版材料的显影过程,通过版材表面白银(亲油部分)的反射光强(Intensity)随CCD单元及反应时间的变化来表征物理显影速率,达到了直观、快速、实时监测物理显影全过程的目的。结果表明CCD技术应用于研究物理显影是完全可行的。     

Experimental study of the influence of temperatures under SCR conditions using an on-line digital image technique

In this paper, the drop tube furnace (DTF) system was utilized to study the ash deposition growth of different temperatures in the mixed atmosphere of NH₃ and SO₃ using an on-line digital image technique. A series of tests, such as XRD, SEM, and EDS, were also used to further study the ash deposition characteristics. The experimental results show that the stable thickness of ash deposition decreases and heat flux at the probe surface increases as the temperature increases. The average ash deposition thickness at the temperatures of 553, 593 and 633  K is 2.13, 1.64 and 1.53 mm, respectively, and the average heat flux is 17.13, 24.19 and 31.33 kW/m², respectively. Ash deposition growth can be divided into three stages: the rapid growth stage, the slow growth stage, and the stable stage. Ammonium bisulfate (ABS) was detected by XRD, and an N element was detected by EDS, indicating the viscous ABS generated in the mixed atmosphere and aggravated fly ash deposition. SEM analysis showed that the ash deposition on the upper part of the probe was mostly agglomerated and the particle size increased, and the lower ash deposition is mostly spherical, similar to the fly ash. In addition, the agglomeration of the upper ash deposition is weakened, and the lower ash deposition becomes smoother and looser as the temperature increases.