Wang Nan, Jiang Wei, Zhang Yu
Opt Express. 2020 Mar 2;28(5):6755-6765. doi: 10.1364/OE.382413.
We explore an easy-to-implement moiré-based measurement scheme for the mask-wafer misalignment in nanoimprint lithography. By introducing the beat signal of moiré fringes, the measurement range increase by dozens or even hundreds of times, while the measurement accuracy doesn't get affected and still kept in nanoscale. Moreover, the alignment signal, collected throughout the whole imprint process, is independent of the wafer-mask gap and beam fluctuation, which makes it very suitable for the misalignment measurement in NIL. The experiment shows that sub-10 nm alignment could be obtained within a measurement range of 500µm, which is expected to be improved after the parameter optimization.
我们探索了一种易于实现的基于莫尔条纹的测量方案，用于纳米压印光刻中掩膜与晶圆的对准误差测量。通过引入莫尔条纹的拍频信号，测量范围增加了数十倍甚至数百倍，而测量精度不受影响，仍保持在纳米尺度。此外，在整个压印过程中采集的对准信号与晶圆 - 掩膜间隙和光束波动无关，这使其非常适合纳米压印光刻中的对准误差测量。实验表明，在500μm的测量范围内可实现亚10nm的对准精度，经过参数优化后有望进一步提高。
