BRIGE: Measurements of Image Formation in Chemically-Amplified Resists

该奖项是根据2009年《美国复苏和再投资法案》(Public Law 111-5)资助的。化学放大抗蚀剂是集成电路高通量构图所必需的，但最近的实验和理论报告表明，这些系统不能同时达到下一代光刻所需的分辨率、灵敏度和线条边缘粗糙度。抗蚀剂设计必须反映这三个因素之间的最佳平衡，但光刻是半导体制造中少数几个没有闭环反馈的工艺之一，因此优化非常复杂。工艺开发在很大程度上依赖于模拟曝光、成像和显影步骤。然后将模拟结果与开发的抗蚀剂结构的扫描电子显微镜测量结果进行比较，以进行验证。智能优点：该研究计划将开发x射线衍射方法来表征化学放大抗蚀剂中的潜像。通过对衍射数据进行建模，可以计算出纳米级精度的图像分辨率、三维形状和图案线边缘粗糙度。目前还没有可用的实验方法来获取这些信息，因此该项目提供了一种独特的策略来确定下一代光刻化学放大的基本限制。将开发一种用于成像过程的现场测量的协议，通过该方法获得的实时反馈可用于新成像材料的过程开发、优化和快速筛选。该计划的关键组成部分如下：-电子束光刻(EBL)将用于在化学放大的抗蚀剂中产生光酸分布。-EBL图案将是在节距中具有低幅度正弦变化的线栅。周期性的节距位移引入了有助于分析的额外衍射峰。-潜在图像的结构将用三种互补的x射线衍射技术来表征：透射式共振软x射线衍射、透射式小角x射线衍射和掠入射小角x射线衍射。每种技术都提供独特的信息。-数据将通过包含图像分辨率、图像横截面形状和图案线边缘粗糙度的模型进行定量分析。将开发用户友好的软件包并与光刻社区共享。广泛的影响：布里奇计划将资助来自代表不足的群体的两名本科生研究人员，他们是在一年级或二年级水平入学的。每个学生都将被分配一个与他们的技能和知识水平相适应的个人项目，他们将学习与微电子制造和纳米材料表征相关的各种实验方法。这些本科生将在休斯敦当地高中的科学课堂上展示他们的研究成果。其目的是向高中生演示在他们科学生涯开始时可以获得的研究机会的类型。

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Chemically-amplified resists are required for high-throughput patterning of integrated circuits, but recent experimental and theoretical reports suggest that these systems cannot simultaneously achieve the required resolution, sensitivity, and line edge roughness for next generation lithography. Resist design must reflect an optimal balance between these three factors, but lithography is one of a few processes in semiconductor manufacturing that does not have closed-loop feedback, so optimization is enormously complex. Process development relies heavily on simulating the exposure, image formation, and development steps. Simulation results are then compared with scanning electron microscopy measurements of the developed resist structures for validation.Intellectual Merit: This research program will develop x-ray diffraction methods to characterize the latent image in chemically-amplified resists. The image resolution, three-dimensional shape, and pattern line-edge roughness will be calculated with nanometer accuracy by modeling the diffraction data. There are currently no experimental methods available to access this information, so this project offers a unique strategy to identify the fundamental limitations of chemical amplification for next generation lithography. A protocol will be developed for in-situ measurements of the image formation process, and the real-time feedback acquired with this approach may be used for process development, optimization, and rapid screening of new imaging materials. The key components to this program are as follows:- Electron beam lithography (EBL) will be used to generate the photoacid distribution in the chemically-amplified resists.- The EBL patterns will be line gratings that have a low-amplitude sinusoidal variation in the pitch. The periodic pitch displacements introduce additional diffraction peaks that will facilitate the analysis.- The structure of the latent image will be characterized with three complementary x-ray diffraction techniques: Transmission resonant soft x-ray diffraction, transmission small-angle x-ray diffraction, and grazing-incidence small-angle x-ray diffraction. Each technique offers unique information.- Data will be quantitatively analyzed with models that incorporate the image resolution, the shape of the image cross-section, and pattern line-edge roughness. User friendly software packages will be developed and shared with the lithography community.Broader Impacts: The BRIGE program will fund two undergraduate researchers from under-represented groups that are enrolled at the freshman or sophomore level. Each student will be assigned an individual project that is appropriate for their level of skill and knowledge, and they will learn a variety of experimental methods that are relevant to microelectronics fabrication and nanomaterials characterization. These undergraduate students will present their work to science classes at local high schools in Houston. The objective is to demonstrate to high school students the types of research opportunities that are available at the start of their scientific careers.