Research On Non-Contact Optical Characterization And On-Chip Optical Effects Of Micro-Nano Structures

Micro-nano structures often endow materials/devices with unique mechanical,physical and chemical properties.The research micro/nano structures in optics field can be divided into two aspects:using optical principles to realize non-contact nondestructive characterization of micro/nano structures on the surface of devices and studying how micro/nano structures affect the optical properties of devices.Non-contact optical characterization of micro-nano structures includes roughness detection and texture orientation detection.Three-dimensional characterization of micro-nano structures can be realized by combining longitudinal roughness information and transverse texture information.And non-contact roughness measurement methods based on optics include white light interference method,confocal microscope method,and scattering method et.al.Scattering method has become an important measurement method for roughness detection because of its advantages of simple structure and convenient.However,the texture orientation measurement of micro-nano structures in two-dimensional plane currently still relies on high-precision large-scale instruments such as confocal microscope.Fast and convenient non-contact texture orientation measurement method has not been reported yet.In this paper,we propose a fast non-contact optical measurement method for the roughness and texture orientation of micro-nano structures based on Beckmann scattering theory by using special optical fiber.At the same time,the study of micro-nano structures effect on the optical properties of devices has become one of the main research directions of on-chip devices in recent years.The specific method is to excite the surface plasmonic polaritons(SPP_S)field on the metal/dielectric interface by etching different micro-nano structures on the metal thin layer.The excited SPP_S field has incomparable advantages over the traditional light field:the SPP_Sfield is limited to the subwavelength scale on the metal/dielectric interface,which lays a foundation of high integration optical devices.And SPP_S has a variety of modulation methods which can be modulated by changing the wavelength,phase,polarization state and other information of the incident light.It is worth noting that the configuration and shape of micro-nano structures also have a great influence on the distribution of SPP_S field.Different micro-nano structures can generate different on-chip SPPs filed.Therefore,it has great significance to study the on-chip optical effects of different micro-nano structures.In this paper,we will study how to use special fiber to realize non-contact optical characterization of micro-nano structures and how to design on-chip optical devices with different functions by processing special micro-nano structures.According to the relationship between the surface roughness and the intensity of the specular light in Beckmann scattering theory,we have designed a high precision roughness sensor based on the annular core fiber and the relative error between the experimental measured value and the nominal value of the standard roughness sample is about 5%.The relationship between the texture orientation and the specular light intensity has also been deduced.Furthermore,we proposed a novel texture orientation sensor based on seven cores fiber.of micro-nano structures affect the signal intensity collected by special optical fiber.In the part of on-chip micro-nano structures optical effect,special micro-nano structures have been designed to realize the all-optical logic device and the structural light field generation device.