Research On The Construction And Spatial Resolution Of Ion Photon Emission Microscopy

The electronic devices used in space need special radiation hardened design for their electronic circuits,which need to determine the radiation sensitive area and the mechanism of radiation effect in circuits and devices,and carry out targeted reinforcement design.Radiation Effect Microscopy(REM)is an effective method to determine the radiation sensitive region of integrated circuits and devices,whose principle is to scan the entire device with a focused ion beam to obtain the sensitive area of the device.However,with the development of modern integrated circuits,there are thicker metal wiring layers above the active area of new devices,and it is very difficult to focus high-energy ions that can penetrate these covering layers to detect the sensitive areas of the device.Ion Photon Emission Microscopy(IPEM)is a new type of device radiation effect microanalysis technology.This technology no longer needs to focus on high-energy ion beams and has great application potential in the future.However,the development of IPEM technology faces the problems of low operation reliability and spatial resolution.Based on this,this paper designs and builds an IPEM system,analyzes the factors affecting the spatial resolution of the IPEM system,and conducts an experimental evaluation on the spatial resolution of the built IPEM system.The main work content and results are as follows:(1)Design and construction of IPEM system.By analyzing the principles and functions of IPEM technology to achieve the requirements for each component,an IPEM system is designed and built.The IPEM system includes two main parts: an optical imaging system and a device testing system.In the design of the optical imaging system,an internal reflection right-angle prism with a hole is used to enable photon collection while ion bombarding the scintillator,which realizes the real-time collection of photons and improves the collection efficiency of photons.The device test system is a transient pulse test system of Au Si surface barrier detector.The whole system realizes online measurement and remote control.(2)The research on the influence factors of space resolution of IPEM system.The effects of energy deposition distribution of ions in scintillator,scattering of photons in optical system and scintillator on the spatial resolution of IPEM system are studied.The results show that the radial energy deposition distribution of ions in scintillator is less than 100 nm,which has little influence on spatial resolution.In the design of the optical imaging system,reducing the thickness of the imaging screen and increasing the numerical aperture NA of the objective lens can improve the spatial resolution of the system.The spatial resolution of the system will be reduced by photon scattering.(3)Experimental evaluation of spatial resolution of the IPEM system.Combining different scintillator materials to evaluate the spatial resolution of the built IPEM system.The experimental results show that the Zn S(Ag)scintillator has a high luminous intensity,and the spot image formed by a single ion incidence can be observed at a low fluence rate,which is suitable for the imaging screen of the IPEM system.A 10μm thick Zn S(Ag)film is used as an imaging screen,and the spatial resolution of the system is about 3μm.In addition,reducing the thickness of the scintillator film can improve the spatial resolution of the system.