Methodological Investigation Of Super Resolution Imaging Based On Plasmonic Resonant Cavity Structure

Due to the evanescent wave which carries sub-wavelength information of objects could not participate in imaging process,the resolution of conventional microscope is restricted by the diffraction limit.The spatial resolution is restricted about half of illumination wavelength.In recent years,with development of surface plasmon,the evanescent wave is controlled and amplified by SP,which achieves super-resolution image.We study how to improve resolution of super-resolution image and lithography in this article.We designed the surface plasmon resonant cavity structure,and sub-wavelength imaging could be realized by the evanescent wave enhancement owing to its amplifying in imaging process.Based on the surface plasmon resonant cavity structure,on the one hand,we designed phase contrast hyperlens to achieve sub-diffraction imaging of nano-transparent objects.On the other hand,combined with SP illumination,the resolution enhancement of lithography could be achieved by the structure we designed.And the main achievements are listed below:1.Far field super resolution phase contrast imaging of nano-transparent objects is studied in the article.We analyzed the phase contrast principle of hyperlens structure.And hyperlens structure based on the surface plasmon is designed to improve phase contrast imaging resolution.As examples,nano-dielectric object imaging is numerically demonstrated with half-pitch resolution about ?/10 and a minimum distinguishable refractive index difference down to 0.15.2.It is introduced that how to generate surface plasmon,and we also analyzed the resolution enhancement of SP resonant cavity structure.The surface plasmon wave illumination structure based on SP resonant cavity structure is designed to enhance lithography resolution and elongate the air working distance.Using this structure,it is demonstrated the half-pitch resolution is about 32 nm.Meanwhile,the simulation is demonstrates the resolvable 60 nm resolution with 120 nm air working distance,which is around 10 times larger than the case of conventional lithography.At the same time,Compared with OAI structure,the peripheral distortion is suppressed.