Oxygen exchange and transport in thin zirconia films on Si(100)

Busch, B.; Schulte, W.H.; Garfunkel, Eric; Gustafsson, T.; Qi, Wen Jie; Nieh, R.; Lee, J.

doi:10.1103/physrevb.62.r13290

Cited by 144 publications

(70 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…11 The HfO 2 deposition has therefore catalyzed the oxidation at the interface between the silicon substrate and the chemically stable ultra thin thermally grown oxide. This increase in interfacial oxide thickness with high-k deposition has previously been observed in a number of studies [12][13][14] and has been identified as forming in the initial phase of deposition. The likely cause of this interfacial oxide growth at room temperature is the enhanced dissociation of O 2 into atomic oxygen in the presence of hafnium atoms due to the metal atom catalytic effect.…”

supporting

confidence: 72%

High resolution photoemission study of SiOx/Si(111) interface disruption following in situ HfO2 deposition

McDonnell

Brennan

Hughes

2009

Applied Physics Letters

View full text Add to dashboard Cite

We report on an in situ high resolution core level photoemission study of the early stages of interface formation between an ultrathin SiO x layer ͑ϳ0.3 nm͒ grown on the atomically clean Si͑111͒ surface and a HfO 2 dielectric layer. Si 2p core level spectra acquired at 130 eV photon energy reveal evidence of a chemically shifted component on the lower binding energy side of the substrate peak which is attributed to interface defect states resulting from the incorporation of silicon atoms from the substrate into the interfacial oxide at room temperature. This evidence of Si/ SiO x interface disruption would be expected to increase charge carrier scattering mechanisms in the silicon and contribute to the generally observed mobility degradation in high-k stacks with ultrathin silicon oxide interface layers.

show abstract

supporting

confidence: 72%

High resolution photoemission study of SiOx/Si(111) interface disruption following in situ HfO2 deposition

McDonnell

Brennan

Hughes

2009

Applied Physics Letters

View full text Add to dashboard Cite

show abstract

“…Interfacial silicides form under reducing conditions [3][4][5]15,16], while silicate layers are often observed at interfaces between Si and rare-earth or related oxides. While the experimental conditions under which these layers form are relatively well understood, significant disparity exists in the literature with respect to the reactions causing the formation of interfacial layers, in particular the silicides [4][5][6][7][8][9]17,18].…”

Section: Introductionmentioning

confidence: 99%

Thermodynamic considerations in the stability of binary oxides for alternative gate dielectrics in complementary metal–oxide–semiconductors

Stemmer¹

2004

Journal of Vacuum Science &Amp; Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena

110

View full text Add to dashboard Cite

A number of binary oxides have been predicted to be thermodynamically stable in contact with Si and are candidates to replace SiO 2 in CMOS. However, reactions leading to the formation of interfacial silicide, silicate or SiO 2 layers have been reported when these oxides are exposed to high temperatures during device processing. Different pathways have been proposed in the literature to explain these reactions. In this paper, a thermodynamic analysis of the proposed reactions is performed. The analysis includes gaseous species, because typical gate dielectrics are ultra-thin layers and diffusivities for species from the surrounding atmosphere, such as oxygen, may be high. Furthermore, nonstoichiometry of the high-k oxide, as may be resulting from nonequilibrium deposition processes or reducing atmospheres during processing is also considered. Studies are proposed to distinguish between possible reaction mechanisms. Finally guidelines for stable interfaces are presented.3

show abstract

“…Postgrowth oxidation in 18 O 2 (98% isotopically enriched) was performed in-situ in the UHV chamber (p base ~10 -9 Torr) connected to the MEIS analysis chamber. The sample was first stabilized at a temperature in the ~ 763 -1223K range (measured by an optical pyrometer and or a K-type thermocouple), followed by 18 31 which is close to the maximum stopping power for protons in Si. Depth profiles of all elements were obtained using a computer simulation code of the backscattered ion energy distributions developed by T. Nishimura.…”

Section: Methodsmentioning

confidence: 99%

Diffusion and interface growth in hafnium oxide and silicate ultrathin films on Si(001)

et al. 2011

Self Cite

View full text Add to dashboard Cite

Medium energy ion scattering (MEIS) has been used in combination with 16 O and 18 O isotope tracing to determine elemental depth distributions and elucidate oxygen transport in 2-5 nm thick HfO 2 and HfSiO x films grown by atomic layer deposition on Si(001). Both the oxygen isotope exchange rate in the dielectric as well as the interfacial silicon oxide growth rates were examined as a function of time, temperature, film stoichiometry (HfO 2 , HfSiO x and HfSiO x N y ) and crystallinity. The amount of exchanged oxygen in the oxide was found to decrease with increasing SiO 2 content. When the SiO 2 to HfO 2 ratio reaches 1:1 in HfSiO x almost full suppression of oxygen exchange is observed. The activation barrier for the SiO 2 growth at the HfO 2 /Si and HfSiO x /Si interface was found to be much lower than that in the SiO 2 /Si and SiO x N y /Si cases, which is attributed to distinctly different oxygen incorporation mechanisms.Primary route for oxygen delivery to the interface responsible for the SiO 2 growth is via exchange, however direct oxidation by molecular oxygen cannot be discounted completely. In the presence of an interfacial nitride layer the 18 O-16 O exchange is replaced by the 18 O-N exchange, which slows diffusion and reduces the oxidation rate.2

show abstract

Oxygen exchange and transport in thin zirconia films on Si(100)

Cited by 144 publications

References 13 publications

High resolution photoemission study of SiOx/Si(111) interface disruption following in situ HfO2 deposition

High resolution photoemission study of SiOx/Si(111) interface disruption following in situ HfO2 deposition

Thermodynamic considerations in the stability of binary oxides for alternative gate dielectrics in complementary metal–oxide–semiconductors

Diffusion and interface growth in hafnium oxide and silicate ultrathin films on Si(001)

Contact Info

Product

Resources

About