Early K, Tennant D M, Jeon D Y, Mulgrew P P, Macdowell A A, Wood Ii O R, Kubiak G D, Tichenor D A
Appl Opt. 1993 Dec 1;32(34):7044-9. doi: 10.1364/AO.32.007044.
Using 14-nm wavelength illumination, we have imaged 0.1-µm-wide lines and spaces in single-layer thin films of the highy sensitive, negative, chemically amplified resist AZ PN114 by usingboth a Schwarzschild 20× camera and an Offner ring field 1× optical system. For soft-x-ray projection lithography the approximate 0.2-µm absorption length in resists at 14-nm wavelength necessitates a multilayer resist system. To explore further the requirements of the imaging layer of such a system, we have transferred patterns, exposed by a high-resolution electron beam in a 60-nm-thick layer of AZ PN114, into the underlying layers of a trilevel structure. Significant pattern edge noise and resist granularity were found. It remains to be determined whether the observed noise is dominated by statistical fluctuations in dose or by resist chemistry. We also investigated pinhole densities in these films and found them to increase from 0.2 cm(-2) for 380-mm-thick films to 15 cm(-2) for 50-nm-thick films.
使用14纳米波长的照明光，我们通过使用施瓦兹希尔德20倍相机和奥夫纳环形场1倍光学系统，对高灵敏度、负性、化学放大抗蚀剂AZ PN114的单层薄膜中0.1微米宽的线条和间距进行了成像。对于软X射线投影光刻，在14纳米波长下抗蚀剂中约0.2微米的吸收长度需要一个多层抗蚀剂系统。为了进一步探索这种系统成像层的要求，我们将由高分辨率电子束在60纳米厚的AZ PN114层中曝光的图案转移到了三层结构的下层。发现了明显的图案边缘噪声和抗蚀剂颗粒度。有待确定观察到的噪声是由剂量的统计波动还是由抗蚀剂化学性质主导。我们还研究了这些薄膜中的针孔密度，发现其从380纳米厚薄膜的0.2平方厘米（-2）增加到50纳米厚薄膜的15平方厘米（-2）。
