Shi Zhong, Kochergin Vladimir, Wang Fei
Luna Innovations, Inc, 3157 State Street, Blacksburg, VA 24060, USA.
Opt Express. 2009 Oct 26;17(22):20538-45. doi: 10.1364/OE.17.020538.
We present a design of a 193 nm superlens imaging structure to enable the printing of 20 nm features. Optical image simulations indicate that the 20 nm resolution is feasible for both the periodic grating feature and the two-slit feature. Nominal depth-of-focus (DoF) position for both features is identified through the image contrast calculations. Simulations show that the two features have a common nominal dose at the nominal DoF to resolve 20 nm critical dimension when a suitable dielectric material is placed between mask and superlens layer. A DoF of micro8 nm is shown to be obtainable for the 20 nm half-pitch grating feature while the respective DoF for the two-slit feature is less than 8 nm which potentially can be enhanced by employing existing lithographic resolution enhancement techniques.
我们提出了一种193纳米超透镜成像结构的设计，以实现20纳米特征的光刻。光学图像模拟表明，对于周期性光栅特征和双缝特征，20纳米分辨率都是可行的。通过图像对比度计算确定了这两种特征的标称焦深（DoF）位置。模拟表明，当在掩膜和超透镜层之间放置合适的介电材料时，这两种特征在标称DoF处具有共同的标称剂量，以分辨20纳米关键尺寸。对于20纳米半间距光栅特征，显示可获得约8纳米的焦深，而双缝特征的相应焦深小于8纳米，通过采用现有的光刻分辨率增强技术可能会提高焦深。
