Wei Zhen, Bai Jian, Xu Jianfeng, Wang Chen, Yao Yuan, Hu Neibin, Liang Yiyong, Wang Kaiwei, Yang Guoguang
Opt Lett. 2014 Dec 1;39(23):6707-10. doi: 10.1364/OL.39.006707.
A focused laser lithographic system combines with vortex laser induced opacity of photochromic layer to write patterns with linewidth below wavelength. A photochromic layer is formed by coating the mixture of metanil yellow and aqueous PVA solution on the photoresist layer. In our system, the center of a lithographic laser with a 405 nm wavelength coincides with the center of vortex laser with a 532 nm wavelength. When a photochromic layer is illuminated by both lasers simultaneously, the absorbance for the lithographic laser decreases at the hollow region of the vortex laser but increases at its annular region, so that a transparent aperture for the lithographic laser is created and its size could be tuned by changing the power of vortex laser; therefore, the linewidth of written patterns is variable. Experimentally, using a 20× lens (NA = 0.4), this system condenses the linewidth of written patterns from 6614 to 350 nm.
一种聚焦激光光刻系统与光致变色层的涡旋激光诱导不透明度相结合，以写入线宽低于波长的图案。通过将间硝基苯黄和聚乙烯醇水溶液的混合物涂覆在光刻胶层上形成光致变色层。在我们的系统中，波长为405nm的光刻激光的中心与波长为532nm的涡旋激光的中心重合。当光致变色层同时被这两种激光照射时，光刻激光在涡旋激光的空心区域的吸光度降低，但在其环形区域增加，从而为光刻激光创建了一个透明孔径，并且其尺寸可以通过改变涡旋激光的功率来调整；因此，写入图案的线宽是可变的。实验上，使用20×透镜（数值孔径=0.4），该系统将写入图案的线宽从6614nm压缩到350nm。
