QQ客服 官方微博 反馈留言

题名	倾斜/旋转紫外光刻技术研究
作者	何凯
学位类别	硕士
答辩日期	2013
授予单位	中国科学院上海光学精密机械研究所
导师	易葵
关键词	倾斜/旋转紫外光刻 仿真模型 MEMS 衍射
其他题名	Study on the inclined/rotated UV lithography technique
中文摘要	倾斜/旋转紫外光刻技术是近年来发展起来的一种新型紫外光刻方法，该方法通过改进传统紫外光刻技术中的曝光方式就可以制备复杂多样的三维微结构，这些微结构在许多新型微机电系统（MEMS)中得到了越来越广泛的关注和应用。尽管倾斜/旋转紫外光刻技术已制备出复杂多样的微结构，但是目前只有少量的工作从倾斜曝光工艺中掩模的空间像以及Snell定律来解释倾斜微结构的成因，尚未建立相对完善的模型来分析倾斜/旋转光刻工艺中物理和化学过程对这些复杂三维微结构的影响。这对优化光刻工艺制作过程，提高微结构制作精度尤为重要。本文在倾斜/旋转紫外光刻技术的曝光成像方面作了初步的探讨，主要内容包括以下几个方面： 通过将标量基尔霍夫衍射理论与光学传输矩阵法结合，并使用快速傅里叶变换技术处理，建立了适用于倾斜/旋转紫外光刻的曝光成像模型（FDKM）。FDKM比时域有限差分法（FDTD）计算速度更快，比菲涅尔积分掩模平移法（FMS）更准确。将FDKM与光刻胶曝光剂量阈值模型结合，建立了倾斜/旋转紫外光刻的快速模拟方法，可以模拟计算倾斜/旋转紫外光刻技术制备的三维光刻胶微结构形貌。 使用该快速模拟方法，计算并比较了紫外光刻倾斜曝光与垂直曝光时光刻图形在光刻胶内的传递，结果表明倾斜曝光时光刻图形畸变更严重。对倾斜/旋转光刻制备的倾斜微柱、V形槽与锥形管三种典型微结构进行模拟仿真，得到微结构的三维轮廓，并提取分析了微结构的特征尺寸与边墙角。模拟结果表明倾斜曝光制备倾斜微柱与V形槽较容易接近理论设计结构，而锥形管需要非常仔细的工艺优化才能符合设计要求。探讨了倾斜/旋转紫外光刻技术制备光刻胶微结构的一些有效评价参数，包括衍射比，几何尺寸，衍射长度，曝光敏感系数。基于上述的几种评价参数，利用建立的倾斜/旋转紫外光刻快速模拟方法详细讨论了工艺参数对微结构特征尺寸与边墙角的影响，这些工艺参数包括：掩模的线宽、掩模到光刻胶表面的距离、曝光倾斜角、光刻胶厚度、光刻胶折射率、光刻胶消光系数以及基底的折射率。最后，以倾斜微柱为例，计算分析了满足特征尺寸与边墙角要求时的掩模光刻胶间隙与曝光剂量的工艺窗口。 总结了倾斜/旋转紫外光刻实验平台设计与前期准备工作，包括曝光光源、旋转平台的一些关键技术参数。优化改进了周期性微结构衍射效率测试平台，使之可以适用于倾斜/旋转紫外光刻制备的周期性微结构光学性能表征，并利用脉冲压缩光栅对该平台的性能进行了验证和评估。
英文摘要	Inclined/rotated UV lithography technique is a new UV lithography technique developed in recent years. By improving the exposure mode in the tradition UV lithography, it can fabricate variety complex 3D microstructures. These microstructures attract more and more attention and are widely applied in many new MEMS. Though variety complex 3D microstructures are acquired by the inclined/rotated UV lithography technique, only a few works on explaining the formation of the inclined microstructures by calculating the mask image in the inclined exposure process based on Snell''s law have been done. Appropriate simulation model has not been set up to analyze the physical and chemical processes’ influence on the 3D microstructures in the inclined/rotated UV lithography. It is important to the process optimization and the improvement of fabrication precision. Some discussion and research on the exposure image in the inclined/rotated UV lithography are presented in this paper. The detail work is as following: By combining the scalar Kirchhoff diffraction theory with the optical transfer matrix method and applying the fast Fourier transform technique, an exposure image model (FDKM, Frequency-domain Kirchhoff Method) for the inclined/rotated lithography is set up. It is demonstrated that this model is quit faster than the Finite Difference Time Domain method (FDTD) and also more accurate than a mask shifting method based on the Fresnel integral (FMS, Fresnel Mask Shifting). By combining FDKM with the photoresist exposure threshold dose method, a fast inclined/rotated lithography simulation model is also set up. This model can be applied in simulate the profile of the 3D microstructures fabricated by the inclined/rotated UV lithography technique. Using this fast inclined/rotated UV lithography model, the transfer of mask patterns into the photoresist in the inclined and vertical exposure process has been calculated and analyzed. It is found that the patterns in inclined/rotated lithography have a stronger aberration than in tradition vertical lithography. Three representative microstructures including an inclined pillar, a V shape and a truncated cone fabricated by inclined/rotated lithography are simulated and analyzed in detail. The 3 dimensions profiles of the microstructures are acquired and the feature size and sidewall angles are measured. It presents that it is relatively simple to fabricate the inclined pillar and the V shape meeting the design requirement, but it needs a careful optimization when fabricating the truncated cone. Several evaluation parameters for the microstructures fabricated by inclined/rotated UV lithography are discussed, including diffraction coefficient, geometric dimensioning, diffraction length, and exposure sensitivity ratio and process window. The influence on the microstructure feature size of several process parameters also have been studied, including mask feature size, proximity distance, exposure inclined angle, resist thick, resist indexes, resist extinction coefficient and the wafer indexes. The process window of the exposure dose and the proximity distance satisfying the feature size and side wall angles requirement have been calculated at last. An experiment platform for inclined/rotated UV lithography is designed and the preparing work is also introduced. A test platform for the diffraction measurement of duty microstructures has been optimize and improved. A pulse compression grating is measured to test and evaluate the platform performance. The platform can be used for the property characterization of duty microstructures fabricated by the inclined/rotated UV lithography.
语种	中文
内容类型	学位论文
源URL	[http://ir.siom.ac.cn/handle/181231/16782]
专题	上海光学精密机械研究所_学位论文
推荐引用方式 GB/T 7714	何凯. 倾斜/旋转紫外光刻技术研究[D]. 中国科学院上海光学精密机械研究所. 2013.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。