| Radiation Effects Microscopy(REM)is an extreme ly useful technique for fa ilure analysis of e lectronic devices in radiation environment.It also provides much needed support for deve lopment of radiation resistant components used in spacecraft and nuc lear weapons.Advancement in integrated c ircuits manufacturing technology has resulted in the increasd thickness of the back end of line on the device,whic h makes the traditiona l microbeam for REM una ble to reach the sensitive regions of the device.A new method,Ion Photon Emission Microscope(IPEM),can determine radiation sensitive regions by recording a secondary photon position in coinc idence with a electrica l signa l.With the advanta ges of unfocused ion beam and simple operation,it has a good deve lopment prospect in the detection of radiation sensitive region of devices.However,there is less study on the measurement of device radiation effect by IPEM technology.In this dissertation,the optica l positioning measurement and transient electrica l signa l test module is designed based on IPEM technology.The transient test of typica l pn junction device(Au-Si surface barrier detector)is carried out,the characteristic parameters of transient electrica l and optical signa ls are analyzed and eva luated,and the coinc idence measureme nt of the collected signa ls is studied.The main work contents and results are as follows:(1)Design and constrution of transient test syste m for pn junction devices.The transient test system of pn junction devices is designed and built by combining the princ iple of IPEM technology,which inc ludes optica l positioning measurement module and transient e lectrica l signa l test module.The optica l positioning measurement module can realize the photon measuring and positioning,and it consists of luminous materia ls,microscope system and displacement platform control system.The transient e lectrical signa l test module can realize the on-line acquisition and analysis of fast transient pulse signa ls,and it consists of the tested device,Bias Tee and high frequency oscilloscope.At the same time,by adopting reflection suppression technology,se lecting appropriate impe dance value and designing noise reduction methods,the influence of interference factors on pulse signa l can be reduced and the efficiency of transient electrical signal acquisition is improved.(2)Study on transient measurement of pn junction devices and ana lysis of system spatia l resolution.The relationship between the a mount of charge collected by the transient pulse and the thickness of the scintillator film and the effect of scintilla tor materia l parameters on the spatia l resolution are studied.The results show that the tra nsient collected c harge is between 1112.69 f C and 2032.8 f C,the corresponding scintillator film thic kness ranges from 23.31 μm～26.99 μm;Based on about 25 μm thick Zn S(Ag)film,the spatia l resolution of the system can reach about6μm.When the thickness of the scintillator film is thinner,the fluorescence dispersion effect will be weaker,the distribution range of ion energy deposition on its surface will be smaller,and the spatial resolution of the system will be better.(3)IPEM system coinc idence measurement study.The influence of de lay time on coinc idence measurement is studied,and the method of drawing two-dime nsional map of c oinc idence events is established.The results show that in the coincidence sequence,the transient signa l is directly proportional to the number of distinguisha ble spot signa ls;By increasing a certain de lay time,the number of coincidence events can be increased,and the corre lation between the transient collected c harge and the spot spatial resolution can be improved. |
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