Tsunehiro Ino

Effects of nitrogen in HfSiON gate dielectric on the electrical and thermal characteristics

The effects of the nitrogen in the HfSiON gate dielectric on the electrical and thermal properties of the dielectric were investigated. It is clearly demonstrated that nitrogen enhances the dielectric constant of silicates. High dielectric constants of the HfSiON are maintained and boron penetration is substantially suppressed in the HfSiON during high temperature annealing. These properties are ascribed to the homogeneity of the bond structure in the film containing nitrogen through high temperature annealing.

Direct Comparison of ZrO2 and HfO2 on Ge Substrate in Terms of the Realization of Ultrathin High-κ Gate Stacks

Direct comparison of ZrO2 and HfO2 on Ge substrates was performed in terms of the realization of an ultrathin gate stack with low leakage current. Changes in the interfacial layer thickness, film dielectric constant and leakage current upon postdeposition annealing were investigated. Considerable thinning of the interfacial layer due to interdiffusion with ZrO2 was observed after annealing. Moreover, the high dielectric constant of ZrO2 was retained even after Ge incorporation by interdiffusion. These phenomena resulted in a small capacitance equivalent thickness (CET) of 1.2 nm. On the other hand, the interfacial layer under the high-permittivity (high-κ) film remained almost the same for HfO2 on Ge stack, resulting in a relatively large CET of 1.6 nm. Together with the fact that the leakage current is lower for the ZrO2 stack than that for the HfO2 stack, ZrO2 is considered to be preferable to HfO2.

Diffusion and activation of n-type dopants in germanium

The diffusion and activation of n-type impurities (P and As) implanted into p-type Ge(100) substrates were examined under various dose and annealing conditions. The secondary ion mass spectrometry profiles of chemical concentrations indicated the existence of a sufficiently high number of impurities with increasing implanted doses. However, spreading resistance probe profiles of electrical concentrations showed electrical concentration saturation in spite of increasing doses and indicated poor activation of As relative to P in Ge. The relationships between the chemical and electrical concentrations of P in Ge and Si were calculated, taking into account the effect of incomplete ionization. The results indicated that the activation of P was almost the same in Ge and Si. The activation ratios obtained experimentally were similar to the calculated values, implying insufficient degeneration of Ge. The profiles of P in Ge substrates with and without damage generated by Ge ion implantation were compared, and it ...

Dielectric properties of noncrystalline HfSiON

The dielectric properties of noncrystalline hafnium silicon oxynitride (HfSiON) films with a variety of atomic compositions were investigated. The films were deposited by reactive sputtering of Hf and Si in an O, N, and Ar mixture ambient. The bonding states, band-gap energies, atomic compositions, and crystallinities were confirmed by X-ray photoelectron spectroscopy (XPS), reflection electron energy loss spectroscopy (REELS), Rutherford backscattering spectrometry (RBS), and X-ray diffractometry (XRD), respectively. The optical (high-frequency) dielectric constants were optically determined by the square of the reflective indexes measured by ellipsometry. The static dielectric constants were electrically estimated by the capacitance of Au/HfSiON/Si(100) structures. It was observed that low N incorporation in the films led to the formation of only Si-N bonds without Hf-N bonds. An abrupt decrease in band-gap energies was observed at atomic compositions corresponding to the boundary where Hf-N bonds start to form. By combining the data for the atomic concentrations and bonding states, we found that HfSiON can be regarded as a pseudo-quaternary alloy consisting of four insulating components: SiO

Determination of Band Alignment of Hafnium Silicon Oxynitride/Silicon (HfSiON/Si) Structures using Electron Spectroscopy

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Careful examination on the asymmetric Vfb shift problem for poly-Si/HfSiON gate stack and its solution by the Hf concentration control in the dielectric near the poly-Si interface with small EOT expense

, HfO

Additional scattering effects for mobility degradation in Hf-silicate gate MISFETs

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Dielectric Constant Behavior of Hf–O–N System

, Si

Effect of Hf-N bond on properties of thermally stable amorphous HfSiON and applicability of this material to sub-50nm technology node LSIs

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Degradation mechanism of HfSiON gate insulator and effect of nitrogen composition on the statistical distribution of the breakdown

N