微压印中抗蚀剂三维微流场可视化实验研究

Visualization experimental research on resist three-dimensional microflow fields in microlithography

为了研究微纳米压印中抗蚀剂的填充行为,采用三维数字离焦微流场测速技术对抗蚀剂内分散的荧光示踪粒子进行粒子离焦图像采集.针对粒子离焦图像的特殊性,提出基于两帧离焦图像的三维粒子跟踪测速(3DPTV)算法.实现了对粒子三维运动轨迹的追踪,构建示踪粒子三维速度场.基于计算流体动力学(CFD)方法建立微压印抗蚀剂填充行为数值计算模型,将可视化实验结果与数值计算结果进行对比,两者吻合较好,证明三维数字离焦微流场测速技术在构建抗蚀剂填充过程微流场中的有效性.

To investigate the resist filling behavior in micro/nanolithography, a three-dimensional （3D） defocusing digital particle image velocimetry （DDPIV） technique was adopted to record the defocused images of the fluorescent tracer particles dispersed in a resist film. A three-dimensional particle tracking velocimetry （3D-PTV） algorithm based on two-frame defocused images was proposed aiming at the particularity of the defocused images of tracer particles. The tracing of the 3D motion trajectories of the particles was realized, and the three-dimensional velocity fields of the particles were constructed. A numerical model based on the computational fluid dynamics （CFD） was built to predict the resist filling behavior, which justifiedthe validity of the DDPIV technique for constructing the micro flow field in the resist filling process.