| AVS 61st International Symposium & Exhibition | |
| Electronic Materials and Processing | Wednesday Sessions |
| Session EM-WeA |
| Session: | High-K Dielectrics for 2D Semiconductor |
| Presenter: | Kai-wen Hsu, University of Wisconsin-Madison |
| Authors: | K.W. Hsu, University of Wisconsin-Madison H. Ren, Applied Materials R.J. Agasie, University of Wisconsin-Madison L. Zhao, Stanford University Y. Nishi, Stanford University J.L. Shohet, University of Wisconsin-Madison |
| Correspondent: | Click to Email |
In order to investigate neutron-induced effects on HfO2 resistive random-access memory (RRAM), HfO2 films are subjected to irradiation by neutrons with energies above 1 MeV. Changes in the defect state concentrations of HfO2 may lead to changes in the states of memory which has the potential to convert a “0” into a “1” in RRAM or vice versa.
Electron-spin resonance (ESR) is used to detect defect-state concentrations of the HfO2 film deposited on high-resistivity substrates. Additionally, leakage currents of HfO2 films are also measured to support the ESR data.1
Neutron irradiation at low fluence decreases the Pb-type and E’ defect levels in ultra-thin HfO2 films because electrons can fill existing states. These electrons come from electron-hole pairs generated by neutron interactions with silicon and oxygen. Thus, a low fluence of neutrons “anneals” the sample. However, when neutron fluence increases, more neutrons collide with oxygen atoms and cause them to leave the lattice or to transmute into different atoms. This causes the E’ state concentration to increase. The changes in the number of defect states lead to changes in leakage currents.
This work was supported by the Semiconductor Research Corporation under Contract 2012- KJ-2359 and by the National Science Foundation under Grant CBET-1066231.
1K-W Hsu, H. Ren, R.J. Agasie, S. Bian, Y. Nishi, and J.L. Shohet, Applied Physics Letters 104 032910 (2014)