Palade C, Slav A, Lepadatu A M, Stavarache I, Dascalescu I, Maraloiu A V, Negrila C, Logofatu C, Stoica T, Teodorescu V S, Ciurea M L, Lazanu S
National Institute of Materials Physics, 405A Atomistilor Street, 77125 Magurele, Romania.
Nanotechnology. 2019 Nov 1;30(44):445501. doi: 10.1088/1361-6528/ab352b.
Trilayer memory capacitors of control HfO/floating gate of Ge nanoparticles in HfO/tunnel HfO/Si substrate deposited by magnetron sputtering and subsequently annealed are investigated for the first time for applications in radiation dosimetry. In the floating gate (FG), amorphous Ge nanoparticles (NPs) are arranged in two rows inside the HfO matrix. The HfO matrix is formed of orthorhombic/tetragonal nanocrystals (NCs). The adjacent thin films to the FG are also formed of orthorhombic/tetragonal HfO NCs. This phase is formed during annealing, in samples with thick control HfO, in the presence of Ge, being induced by the stress. In the rest of the control oxide, HfO NCs are monoclinic. Orthorhombic HfO has ferroelectric properties and therefore enhances the memory window produced by charge storage in Ge NPs to above 6 V. The high sensitivity of 0.8 mV Gy to α particle irradiation from a Am source was measured by monitoring the flatband potential during radiation exposure after electrical writing of the memory.
首次研究了通过磁控溅射沉积并随后退火的HfO/隧道HfO/硅衬底中由锗纳米颗粒的控制HfO/浮栅组成的三层存储电容器在辐射剂量测定中的应用。在浮栅（FG）中，非晶锗纳米颗粒（NPs）在HfO基质内排成两排。HfO基质由正交/四方纳米晶体（NCs）组成。与FG相邻的薄膜也由正交/四方HfO NCs组成。这种相是在退火过程中，在具有厚控制HfO的样品中，在锗存在的情况下，由应力诱导形成的。在其余的控制氧化物中，HfO NCs是单斜晶系的。正交HfO具有铁电特性，因此将锗纳米颗粒中电荷存储产生的存储窗口提高到6 V以上。通过在存储器电写入后监测辐射暴露期间的平带电位，测量了对来自镅源的α粒子辐照的0.8 mV/Gy的高灵敏度。
