Investigation Of Proton-induced Single Event Upset In Nanometer SRAM

Radiation effects including single event effect (SEE), total ionizing damage(TID) and displacement damage(DD) is particular important and has been ad-dressed by numerous approaches.This work focus on proton induced single event upset (SEU) in nanometer SRAM device.As described by the Moore's Law, the number of transistor per integrated circuit (IC) has doubled about every two years. The development of the semi-conductor industry is indeed continuous progress and development as described as Moore's Low. The emerge of the amazing scientific and technological achievements continues facilitate human's life and work. Although the development of the semi-conductor industry is exciting, but it also brought some new problems, especially in the field of aerospace applications. The feature size of semiconductor device is getting smaller and smaller, the bias voltage is becoming lower and lower, and the operating frequency is getting higher and higher, which leading to the nanometer device is more and more sensitive to the proton induced radiation effects. The work of this paper is based on this foundation.In this work, 25 MeV/u Kr ions and 9.5 MeV/u Bi ions are obtained by using the Heavy Ion Research Facility in Lanzhou (HIRFL), proton range from 1.0 MeV to 8.0 MeV are gained from the Institute of Heavy Ion Physics of Peking University, and proton beam with primary energy is 200 MeV is gained by using the proton irradiation facility of Paul Scherrer Institut (PSI). A series of studies have been carried out using these particle beams, we studied the SEU of the nanometer SRAM device under different beam parameters (energy, LET,etc. )and device parameters (data pattern, bias voltage, temperature, etc.) Moreover,the internal structure information of the experimental device is analyzed by means of scanning electron microscope (SEM) , and the related device model is established.Then the detailed proton induced SEU on nanometer device are analyzed by using Monte Carlo simulation method.The major work of this doctoral thesis is about proton induced SEU on nanometer SRAM device, which is structured as follows:· Experimental study on SEU induced by low energy proton (LEP) direct ion-ization on nanometer device. In this work, the SEU sensitivity of nanome-ter SRAM to LEPs under different experimental and device operating are mainly studied. Experimental results indicate that the nanometer SRAM is very sensitive to the SEU caused by LEPs, and the SEU cross section caused by LEPs can be orders magnitude higher than that of high energy proton.Since the proton's Bragg peak is very narrow, the LEP induced SEU is very sensitive to proton energy and has a large difference for different bias voltage and temperature. The SEU cross section induced by LEP keeps constant under different loaded data patterns.·The SEU cross section induced by high energy (indirect ionization) is investi-gated by experiment.In order to study the difference of the direct ionization and indirect ionization induced SEU on the nanodevice, we carried out a high energy proton induced SEU in the nanodevice study.·The impact of energy straggling on proton induced SEU in the 65nm nan-odevice is studied. Simulation result indicate that when conducting a SEU test on a nanodevice, the impact of energy straggle is mainly reflected in the following three aspects. First, the energy straggle will result in erroneous threshold energy of proton-induced SEU. Second, it will lower the peak value of the proton induced SEU cross section by direct ionization significantly.Third, it may change the SEU cross section curve trend for high energy proton.·The on-orbit soft error rate is predicted for the 65-nm SRAM using the Space Radiation 7.0 toolkit. The prediction result indicated that the on-orbit soft error rate caused by low energy proton can not be ignored.