冷压印光刻工艺精密定位工作台的研制

High-Precision Orientation Stage for Room-Temperature Imprint Lithography

冷压印光刻工艺是一种将模板图形翻制到硅片上的技术。为了获得高分辨率压印图形 ,为压印光刻机设计了一个精密定位工作台。精密定位工作台是压印光刻机的关键部件 ,它既能够保证模板 -抗蚀剂 -硅片结构间的接触均匀一致 ,并实现模板与承片台间的三个运动自由度 ,即沿 z轴的直线运动和绕 x、y轴的旋转运动 (α和β) ,又可以实现步进对准所需要的沿x、y轴的直线运动和绕 z轴的旋转运动 ( θ)。设计中采用了柔性机械结构 ,消除了使用铰链连接所引起的间隙与摩擦等问题。压印实验结果显示定位系统在 2 0 0 mm的行程中 ,精密定位工作台定位精度达到 8nm以内。实现了压印光刻工艺在集成电路制造中的高精度定位要求。

Room-temperature Imprint Lithography (IL) is a technique that uses the topography of a template to define the pattern created on the silicon substrate. A high-precision orientation stage was designed for high-resolution imprint machines. The high-precision orientation stage is the critical component of an imprint machine and the template's relative motion to wafer was analysed. Presence of sliding contacts in mechanical joints may cause wear, generate undesirable particles and lead to friction, so all joints were made with flexure mechanism. The high-precision orientation stage is with six degrees of freedom. It can be accomplished with one translation ( z displacement) and two tilting motions ( α and β ) to provide uniform intimate contact between the template and wafer surfaces. And also it can be accomplished with two translations ( x and y displacements) and one tilting motions (θ) between two flats to provide high orientation precision. Imprint experiments were performed and the positioning accuracy achieves within 8nm over 200 mm stroke.