We report here the fabrication of freestanding HfO2 grating by combining fast atom beam etching (FAB) of HfO2 film with dry etching of silicon substrate. HfO2 film is deposited onto silicon substrate by electron beam evaporator. The grating patterns are then defined by electron beam lithography and transferred to HfO2 film by FAB etching. The silicon substrate beneath the HfO2 grating region is...

We report the development of single, locally crystallized nanopores in HfO2 membranes for biosensing applications. HfO2 is chosen for its isoelectric point of 7.0, mechanical and chemical stability in solution, and for its potential as a high-k material for nanopore ionic field effect transistor applications. The HfO2 membrane is deposited on a graphene layer suspended over a 300 nm FIB hole, w...

Soft x-ray photoelectron spectroscopy with synchrotron radiation was employed to study the valence-band offsets for the HfO2 /SiO2 /Si and HfO2 /SiOxNy /Si systems. We obtained a valence-band offset difference of 21.0560.1 eV between HfO2 ~in HfO2/15 Å SiO2 /Si! and SiO2 ~in 15 Å SiO2 /Si!. There is no measurable difference between the HfO2 valence-band maximum positions of the HfO2/10 Å SiOxNy...

With HfO2 filled into the microcavities of the porous single-crystal silicon, the blue photoluminescence was greatly enhanced at room temperature. On one hand, HfO2 contributes to the light emission with the transitions of the defect levels for oxygen vacancy. On the other hand, the special filling-into-microcavities structure of HfO2 leads to the presence of ferroelectricity, which greatly enh...

The HfO2/TiO2/HfO2 trilayer-structure resistive random access memory (RRAM) devices have been fabricated on Pt- and TiN-coated Si substrates with Pt top electrodes by atomic layer deposition (ALD). The effect of the bottom electrodes of Pt and TiN on the resistive switching properties of trilayer-structure units has been investigated. Both Pt/HfO2/TiO2/HfO2/Pt and Pt/HfO2/TiO2/HfO2/TiN exhibit ...

Conductive oxides RuOx as alternative electrode on high-k HfO2 gate dielectric have been fabricated by ultrahigh-vacuum sputtering and subsequently oxidized using oxygen plasma. The energy-band alignment for the RuOx /HfO2/Si system and the oxidation-state dependence of barrier height for RuOx contacting to HfO2 dielectrics has been analyzed by x-ray photoemission spectroscopy. The valenceand c...

We compare the charging response of rapid thermally annealed 800 and 1000 °C 4 nm thick HfO2 to as-deposited HfO2 on Si by measuring the surface potential of the HfO2 layers after vacuum ultraviolet VUV irradiation with 11.6 eV photons. From VUV spectroscopy, we determined all HfO2 layers show the presence of oxygen-interstitial defects OIDs . The electronic states of OID in HfO2 line up in ene...