真空精密工作台结构设计.doc

本科学生毕业论文真空精密工作台结构设计系部名称： 机电工程学院 专业班级：机械设计自造及其自动化 07-9 班学生姓名： 指导教师： 陈佳莹 职 称： 讲 师 黑 龙 江 工 程 学 院二○一一年六月The Graduation Thesis for Bachelor's DegreeThe Structure Design of Vacuum Precision WorktableCandidate：Ge LipengSpecialty：Mechanical Design andManufucture & AtuomationClass：07—09Supervisor： Heilongjiang Institute of Technology2011-06·Harbin黑龙江工程学院本科生毕业设计- I -摘 要光刻机工作时所要达到得很高的精度，对机械系统的传动机构和导轨都有很高的要求，因此，一般的滑动导轨的丝杠都不能满足这些要求基于此，本课题采用了具有高精度，高平稳性的空气轴承来代替传统的导轨，传动件则采用精度很高的滚珠丝杠，以滚动代替普通丝杠滑动来提高精度，从而保证光刻机的加工精度。

兼之电子束正常工作时的高真空度给抽真空和密封上带来的高难要求，本课题在设计中力求减少真空体积，并采用蛇皮管提出解决方案本课题主要解决了以上问题，故本文主要以总体设计，滚珠丝杠，空气轴承三部分来介绍本系统结构简单合理，运行可靠，操作简易完全，无污染，易于使用关键词：导轨；空气轴承；滚珠丝杠；真空；黑龙江工程学院本科生毕业设计- II -ABSTRACTBecause the high precision that photoetching machine must achieve when working poses a high standard for the gearing and guide of mechanical system, neither ordinary sliding guide nor guide screw is able to meet these demands. Therefore, in this subject, the author adopts air bearing with high precision and stability to replace the traditional guide and uses hall guide screw as transmission part which is rolling instead of sliding generally adopted by ordinary guide screw to improve precision, thus guarantees the processing precision of photoetching machine. Meanwhile,the high vacuum degree demanded by electron beam to work normally brings many difficulties tovacuum pump and sealing. The author strives to decrease vacuum volume when designing the subject and adopts flexible conduit to propose a solution. This paper is just to solve the above-mentioned problems and is introduced as follows general design, ball guide screw and air bearing.This system has a simple and reasonable structure, reliable function, easy and complete operation and no pollution, thus, it is easy to adopt this system.Key words: Guide; Air Bearing ;Ball Guide Screw; Vacuum;黑龙江工程学院本科生毕业设计- III -目 录摘要······························································ⅠAbstract···························································Ⅱ第 1 章 绪论·······················································111.1 可控式室内微型移动小车···········································111.2 可控式室内微型移动小车的分类·····································111.3 国内外研究现状及发展趋势········································12第 2 章 机械部分设计··············································132.1 设计任务··················································132.2 确定机械传动方案················································132.3 直流伺服电动机的选黑龙江工程学院本科生毕业设计- IV -择·········································142.4 联轴器的选择············································172.5 蜗杆传动设计···········································182.6 轴的设计·························································212.7 滚动轴承选择计算·······································282.8 本章小结·························································33第 3 章 关键零部件结构设计······································343.1 控制系统总体方案················································343.2 鉴向·····························································343.3 计数的扩展·······················································353.4 中断的扩展·······················································37黑龙江工程学院本科生毕业设计- V -3.5 数模转换器的选择·················································393.6 电机驱动芯片选择················································403.7 运动学分析·······················································443.8 控制软件设计·····················································453.9 本章小结·························································52结论···································································53参考文献······························································54致谢···································································55黑龙江工程学院本科生毕业设计- 1 -第 1 章 绪 论1.1 课题背景在半导体光刻、微型机械、精密测量、超精密加工、需要十分精确的定位和非常精细的运动,随着集成电路集成度的提高,线宽已向着低于亚微米的方向发展,为适应超大规模集成电路器件的发展 ,微电路图形的特征线宽愈来愈细的特点 ,发展了电子束光刻而电子束光刻由于其极高的分辨率 ,可以达到 0.1μｍ ,这是一种直写的刻划方式 ,利用电子束的连续偏转在硅片上“书写”出所需的微电路图形。

因此对未来的大规模集成电路器件的制作具有很大的应用潜力随之而来的是要有高精度的定位工作台 ,以保证高精度的定位要求针对电子束在真空中工作这一特性,因此开发一种高精度真空工作台,就成为实际的需要1.2 国内外的发展情况 因为真空精密工作台的主要部分是它的精密工作台部分，所以以下主要针对精密工作台来讲它的当今发展情况在半导体光刻、微型机械、精密测量、超精密加工、微型装配、生物细胞操纵和纳米技术等领域,需要十分精确的定位和非常精细的运动,因此高性能的超精密定位工作台成为了这些领域的技术支持例如:随着集成电路集成度的提高 ,线宽已向着低于亚微米的方向发展,因此在制造过程中对其定位精度有着苛刻的限制在机械加工非圆球面时,为了得到精确的形状和高质量的表面,对加工过程中刀具相对工件的运动精度提出了严格的要求已有的ＭＥＭＳ加工工艺适宜制造二维或准三维的微型机械结构想得到复杂的微型三维结构,目前较可行的方法是采用微装配技术,即将ＭＥＭＳ加工制造的微型结构通过一定的方式装配起来要实现微装配,需要结构小巧、在平面内有较大行程的超精密载物工作台而为了加大扫描隧道显微镜(ＳＴＭ)的测量范围,还需要高精度的工作台与测头一起实现大范围超精密定位。

实现亚微米甚至纳米级的定位,常规的驱动和传动方式不再适合比如,通常为了实现精密定位,往往采用伺服电机驱动和精密丝杠传动的方案,然而此种定位方式由于螺纹空程和传动摩擦的存在,其定位精度一般只能达到微米级因此,寻求特殊的驱动和传动方式,以使工作台具有纳米级的位移分辨率成为了必须能够实现亚微米和纳米级定位的超精密工作台大致可分为:电磁式工作台、直线电机式工作台、压电式工黑龙江工程学院本科生毕业设计- 2 -作台、摩擦驱动式工作台、ＭＥＭＳ工作台和其它类型的工作台1.2.1 电磁式工作台 电磁式工作台利用电磁吸附力对工作台进行驱动,以实现超精密定位卡罗来纳大学精密工程小组和麻省理工学院机械工程系联合研制了原子级精密运动控制台它依靠六个电磁致动器和六个电容传感器的合理配置,提供控制力和位移反馈,该工作台能实现三维六自由度的精密运动重三公斤的平台悬浮于油中以增加电磁支撑的性能作为样品的定位平台,它被成功地应用于隧道显微镜(ＳＴＭ)中从ＳＴＭ得到的图像表明在 5ｓ的时间内,平台定位噪声的峰值小于 0.2ｎｍ电容传感器的测。