共光路多自由度运动误差测量及补偿技术研究

Research on Measurement and Compensation Technology of Multi-degree Freedom Motion Error in Common Optical Path

工件台是TFT阵列基板长寸测量设备中最为核心的技术单元之一,其定位精度将直接决定最终长寸测量设备的测量精度。在运动过程中由于运动导轨加工和装配误差会使工件台产生运动误差,而这些运动误差会影响TFT阵列基板长寸测量精度。为解决上述工件台运动误差对长寸测量精度的影响,文中基于桥式结构的长寸测量设备研究分析了工件台运动误差对长寸测量精度的影响机理,设计了一种共光路多自由度激光干涉仪测量系统,给出了激光干涉仪测量系统光束结构布局及测量补偿方案。通过搭建测试平台,基于4.5代基板对比测试了工件台运动误差补偿前后的重复性及最终长寸测量重复性。试验结果表明,研究的工件台运动误差测量及补偿技术可以满足100 nm高精度运动台定位精度技术需求。

The workpiece table is one of the most core technical units in the TFT array substrate long-inch measurement equipment,and its positioning accuracy would directly determine the final measurement accuracy.During the movement of the workpiece table,it would produce movement errors due to the processing and assembly errors of the moving guide rail,which could affect the measurement accuracy of the TFT array substrate.In order to solve the above-mentioned influence of the movement error of the workpiece table,the mechanism of the influence of workpiece table movement error on the measurement accuracy of long inches was analyzed based on the bridge structure of the long measuring equipment,and a common optical path with multiple degrees of freedom was designed.The laser interferometer measurement system could provide the beam structure layout and measurement compensation scheme of the laser interferometer measurement system.By building a test platform,the repeatability before and after compensation of the motion error of the workpiece stage and the repeatability of the final long-inch measurement were tested based on the 4.5-generation substrate.The test results show that the workpiece table movement error measurement and the compensation technology studied above could meet the technical requirements of 100 nm high-precision positioning accuracy of the movement table.