Effect of postdeposition anneals on the Fermi level response of HfO2/In0.53Ga0.47As gate stacks

Abstract

The electrical characteristics, in particular interface trap densities, oxide capacitance, and Fermi level movement, of metal oxide semiconductor capacitors with HfO 2 gate dielectrics and In 0.53 Ga 0.47 As channels are investigated as a function of postdeposition annealing atmosphere. It is shown, using both conductance and Terman methods, that the Fermi level of nitrogen annealed stacks is effectively pinned at midgap. In contrast, samples annealed in forming gas show a large band bending in response to an applied gate voltage and a reduced midgap interface trap density compared to those annealed in nitrogen.

Frequency dispersion in III-V metal-oxide-semiconductor capacitors

“…This also explains experimental results that show simultaneous reduction in dispersion in accumulation and depletion upon annealing. 8,23,27 To determine if the observed frequency dispersion in accumulation can be described quantitatively by the recombination-controlled tunneling mechanism, normalized plots of G p =x versus log frequency are shown in Figs. 3(a) and 3(b)).…”

“…The interface trap state distribution in the band gap depends largely on the specific III-V semiconductor. [3][4][5][6] For example, the D it of dielectric/n-In 0.53 Ga 0.47 As interfaces is sufficiently low to achieve band bending (semiconductor Fermi level movement) in the upper half of the semiconductor band gap under an applied voltage, 7,8 resulting in significant device demonstrations. 9,10 One of the most important unresolved issues, however, remains the lack of understanding of the large frequency dispersion that is observed in accumulation, for example, for dielectrics on n-In 0.53 Ga 0.47 As.…”

Diffusion of In0.53Ga0.47As elements through hafnium oxide during post deposition annealing

“…10 Similarly, electrical measurements have shown that annealing in N 2 and/or FGA can reduce the D it of high-k/III-V gate stacks. 3,[11][12][13][14] However, the effect of these treatments on the chemical composition of the samples has not been fully understood.…”

Hydrogen-Induced Rupture of Strained Si─O Bonds in Amorphous Silicon Dioxide

“…It may also shed new light on the behavior of atomic hydrogen in other amorphous solids, in which H 0 is thought to interact negligibly [1], as well as on the so-called hydrogen spillover [57]. Moreover, it has recently been reported by many researchers that application of catalytic metal electrodes such as Pt [58], Pd [59], or Ru [60], in combination with annealing in H-containing ambient allows one to improve the electrical properties of a wide range of device structures. This observation points towards the effect(s) of atomic H; since the reversible behavior expected for the classical passivation-depassivation scheme is not reported, the most plausible explanation is the interaction of hydrogen with amorphous interlayers or grain boundaries in a way similar to the mechanism described here for a-SiO 2 .…”