| Ferroelectric field-effect transistor（Fe FET）memory has good prospects for applications in aerospace and other fields due to its low power consumption,fast read/write speed,non-volatile and unique radiation resistance.With the discovery of ferroelectricity in Hf O2 thin films,Hf O2-based Fe FETs have become one of the research hotspots in the field of nonvolatile memories due to their excellent CMOS compatibility.However,before Hf O2-based Fe FETs can be applied to harsh radiation environments,their radiation resistance must be thoroughly studied.Currently,Hf O2-based Fe FET devices are still in research,and it is difficult to conduct irradiation experiments on the devices.Numerical simulation of radiation effects can simulate the physical process of the particle-matter interaction as well as the device-level reliability analysis,and it is an effective tool in the evaluation for radiation hardness.This paper takes HZO(Hf0.5Zr0.5O2)based fully depleted silicon-on-insulator（FDSOI）Fe FET as the research object,and studies its radiation effect based on Monte Carlo method and Technology Computer Aided Design（TCAD）tools.The main research contents and results are as follows:（1）Simulation of the radiation damage of Ti N/HZO/SiO2/Si metal ferroelectric insulator semiconductor（MFIS）gate structures under the incident of low-energy protons（10 ke V-100 ke V）and heavy ions（100 ke V-2 Me V）based on the Monte Carlo method.The results show that the incident particle energy is mainly deposited in the HZO ferroelectric film,and the damage can be produced in the Si material when the low-energy proton energy exceeds 70 ke V and the heavy ion energy exceeds 1 Me V.The ionization energy loss produced by the incident particle in the MFIS gate structure is dominant,but the non-ionization energy loss is not negligible when the heavy ion energy is low（≤100 ke V）.After the injection of particles,the HZO ferroelectric film produces the most oxygen vacancies,and the concentration of oxygen vacancies caused by heavy ions is much greater than that caused by low-energy protons,which causes more serious damage to the thin films.（2）TCAD-based study of the effects of different incidence positions and angles of heavy ions and drain bias on HZO-based FDSOI Fe FET storage cells.The results show that the polarization state in the ferroelectric layer will not be reversed when heavy ions are incident from different positions,but the output voltage of the storage unit will be affected,and the most sensitive region is close to the drain body junction region.With the decrease of the incident angle of heavy ions,the peak value of the output voltage of the storage unit increases,and the influence of the change of the incident angle is more obvious when reading data is“0”rather than“1”.The peak value of the output voltage of the storage unit is affected by the drain bias voltage,and it is more affected when reading data is“1”rather than“0”.（3）TCAD-based study of the effect of total dose effect on the storage performance of the device after the introduction of ionizing radiation trap charges on the HZO ferroelectric layer,oxide buried oxygen layer and Si3N4 isolation layer of the device.The results show that the introduced trap charges have a small effect on the device storage performance after 1 Mrad（Si）γray irradiation.But after 10 Mrad（Si）γray irradiation,the positive trap charges introduced in the buried oxygen layer causes the device ID-VG curve to drift severely,resulting in a higher probability of data error when the storage cell reads data"0".At the same time,the negative trap charges introduced by the ferroelectric layer and the isolation layer lead to a higher probability of data error when the memory cell reads"1". |
