Impact of total ionizing dose irradiation on Pt/SrBi2Ta2O9/HfTaO/Si memory capacitors

Abstract

In this work, metal-ferroelectric-insulator-semiconductor (MFIS) structure capacitors with SrBi2Ta2O9 (300 nm) as ferroelectric thin film and HfTaO (6 nm, 8 nm, 10 nm, and 12 nm) as insulating buffer layer were proposed and investigated. The prepared capacitors were fabricated and characterized before radiation and then subjected to 60Co gamma irradiation in steps of two dose levels. Significant irradiation-induced degradation of the electrical characteristics was observed. The radiation experimental results indicated that stability and reliability of as-fabricated MFIS capacitors for nonvolatile memory applications could become uncontrollable under strong irradiation dose and/or long irradiation time.

Structural, ferroelectric and dielectric properties of Na0.5Bi0.5(Ti0.98Fe0.02)O3 thin films on different substrates

“…When the voltages sweep from ±4 to ±6 V, the hysteresis loops increase due to the increased ferroelectricity. The maximum memory window is 2 V obtained at ±6 V. However, with the voltages increasing from ±6 to ±10 V, the gradually enhanced positive charges injection occurs, the traps in the film will be filled up and then the space charges will be appear [28]. This results in the shift of the V FBf and V FBr toward the negative voltage and the significant decrease of the memory window.…”

Impact of Radiation Effect on Ferroelectric Al-Doped HfO2 Metal-Ferroelectric- Insulator-Semiconductor Structure

“…However, the radiation mechanisms of HfO2-based FeFET or Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure have not been clearly understood yet. Our previous work showed that irradiation-induced electrical characteristics degradation of MFIS structure of Pt/SrBi2Ta2O9/HfTaO/Si were found under the total dose of 10 Mrad (Si) [11]. D. J. McCrory et al verified the defects induced by γ-ray radiation to be an O2coupled to a hafnium ion of TiN/Ti/HfO2/TiN RRAM devices through electrically detected magnetic resonance (EDMR) [12].…”

A versatile and compact high-intensity electron beam for multi-kGy irradiation in nano- or micro-electronic devices

“…The development of resistant materials in harsh radiation environments is of prime importance for the reliability of systems in aerospace, nuclear and military industries 1 . Hardening studies of micro and nanoscale electronic circuits are currently performed under irradiation doses ranging from 1 Gy to a few tens of kGy [2][3][4][5][6][7][8][9][10][11] . Strong alterations of performances are observed for doses larger than 1 kGy.…”

“…Strong alterations of performances are observed for doses larger than 1 kGy. For instance, if the stability of nanometer size memory capacitors is strongly degraded by irradiation, "writing" operations in memories are prevented 2 . The modification of carrier mobility and the reduction of diffusion length have been observed in sub-micrometer scale AlGaN/GaN transistors 10 leading to severe issues for applications in radiation environments.…”

“…The energy of the electrons and γ-rays delivered by these sources is in most cases larger than 1 MeV, thereby reducing the probability of particle interactions into micrometer-size samples. Consequently, strong activities are necessary to reach a few hundred of Gy per hour 2 . Then, in order to reach kGy doses in micro or nanoscale devices, very long irradiation times are required, under severe radioprotection conditions.…”