Impacts of Annealing Conditions on the Flat Band Voltage of Alternate La2O3/Al2O3 Multilayer Stack Structures

Abstract

The mechanism of flat band voltage (VFB) shift for alternate La2O3/Al2O3 multilayer stack structures in different annealing condition is investigated. The samples were prepared for alternate multilayer structures, which were annealed in different conditions. The capacitance-voltage (C-V) measuring results indicate that the VFB of samples shift negatively for thinner bottom Al2O3 layer, increasing annealing temperature or longer annealing duration. Simultaneously, the diffusion of high-k material to interfaces in different multilayer structures and annealing conditions is observed by X-ray photoelectron spectroscopy (XPS). Based on the dipole theory, a correlation between the diffusion effect of La towards bottom Al2O3/Si interface and VFB shift is found. Without changing the dielectric constant k of films, VFB shift can be manipulated by controlling the single-layer cycles and annealing conditions of alternate high-k multilayer stack.

Interface Chemistry and Defect State Optimization of the ErSmO/InP Heterojunction Modified by ALD-Driven Al2O3 Interlayers

“…The shift in flat-band voltage is related to the dipole between the high-k/interface layers, and the oxygen density difference accommodation model applies to the explanation of interface dipole layer generation owing to its wide support in high-k materials . The dipole layer arises through the migration of O ions from high to low concentrations, leading to the formation of an internal electric field at the interface, while the direction and magnitude of the internal electric field are consistent with the observed flat-band voltage shift. , The dipole species at the ErSmO dielectric/InP interface have an impact on the flat-band voltage shift, and during preparation, the high-k dielectric diffuses into the Al 2 O 3 /InP interface, where the Er and Sm elements are less electronegative than Al and form dipoles with stronger polarities, which can lead to negative flat-band voltage shifts, as indicated by the detected negative flat-band voltages . The ALD 20c sample has the smallest V fb among all samples, indicating that a proper passivation cycle Al 2 O 3 inhibits this process and creates a better interface.…”

“…42,43 The dipole species at the ErSmO dielectric/InP interface have an impact on the flat-band voltage shift, and during preparation, the high-k dielectric diffuses into the Al 2 O 3 /InP interface, where the Er and Sm elements are less electronegative than Al and form dipoles with stronger polarities, which can lead to negative flat-band voltage shifts, as indicated by the detected negative flat-band voltages. 44 The ALD 20c sample has the smallest V fb among all samples, indicating that a proper passivation cycle Al 2 O 3 inhibits this process and creates a better interface. The extracted EOTs of the four samples were 7.32, 7.23, 2.08, and 2.41 nm.…”

3D‐printed surface‐modified aluminum nitride reinforced thermally conductive composites with enhanced thermal conductivity and mechanical strength

“…The XPS was analyzed to prove that this functional group, identified by FTIR, is chemically bound to the filler surface (Figure 2B,C). The C 1s and O 1s deconvolution peak of f‐AlN has binding energy peaks corresponding to C═O (or O═CO) and CO, and the presence of the SiOAl peak can be evidence of silane grafting 23,24 …”

Comparison of high-k Y2O3/TiO2 bilayer and Y-doped TiO2 thin films on Ge substrate

“…On the other hand, V fb is not significantly different from the ideal V fb in the YTO thin film. This means that the homogeneously mixed YTO film eliminates the charge dipole and hardly forms a fixed charge at the Ge/YTO interface [35].…”