Spectroscopic study of chemical phase separation in zirconium silicate alloys

Rayner, G. B.; Kang, Do Kyun; Lucovsky, G.

doi:10.1116/1.1593646

Cited by 68 publications

(62 citation statements)

References 11 publications

(23 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Silicate and aluminate alloys of Zr, Hf and La oxides are often used instead of the pure metal oxides in order to have a higher resistance to crystallisation [19,20,35]. Zr silicate has been the most widely studied.…”

Section: Alloy Crystallisationmentioning

confidence: 99%

High dielectric constant oxides

Robertson

2004

Eur. Phys. J. Appl. Phys.

1,530

828

View full text Add to dashboard Cite

Abstract. The scaling of complementary metal oxide semiconductor (CMOS) transistors has led to the silicon dioxide layer used as a gate dielectric becoming so thin (1.4 nm) that its leakage current is too large. It is necessary to replace the SiO2 with a physically thicker layer of oxides of higher dielectric constant (κ) or 'high K' gate oxides such as hafnium oxide and hafnium silicate. Little was known about such oxides, and it was soon found that in many respects they have inferior electronic properties to SiO2, such as a tendency to crystallise and a high concentration of electronic defects. Intensive research is underway to develop these oxides into new high quality electronic materials. This review covers the choice of oxides, their structural and metallurgical behaviour, atomic diffusion, their deposition, interface structure and reactions, their electronic structure, bonding, band offsets, mobility degradation, flat band voltage shifts and electronic defects. The use of high K oxides in capacitors of dynamic random access memories is also covered. PACS

show abstract

Section: Alloy Crystallisationmentioning

confidence: 99%

High dielectric constant oxides

Robertson

2004

Eur. Phys. J. Appl. Phys.

1,530

828

View full text Add to dashboard Cite

show abstract

“…These differences are addressed in detail in Ref. [20], with the most important aspect of the separation being in the characteristic size of the crystallites or grains in Zr phase. This is ~3 to 5 nm for x < 0.5, and in excess of 10 nm for x > 0.5.…”

Section: Experimental Studies Of Electronic Structurementioning

confidence: 99%

“…Figure 8(b) contains a comparison between the spectrum for the annealed 60% ZrO 2 alloy in trace (i) and an as-deposited alloy in trace (ii). The spectral assignments remain the same, but all of the features in trace (i) are broadened due to the non-crystalline bonding arrangements [20]. Figure 9 displays the spectra of three non-crystalline silicate alloys with concentrations of 70%, 50% and 25% HfO 2 , accurate to approximately ±7% [21].…”

Section: Experimental Studies Of Electronic Structurementioning

confidence: 99%

Spectroscopic studies of metal high‐k dielectrics: transition metal oxides and silicates, and complex rare earth/transition metal oxides

Lucovsky

Hong

Fulton

et al. 2004

Physica Status Solidi (b)

Self Cite

View full text Add to dashboard Cite

PACS 78.70.DmThis paper uses X-ray absorption spectroscopy to the study of electronic structure of the transition metal oxides TiO 2 , ZrO 2 and HfO 2 , Zr and Hf silicate alloys, and the complex oxides, GdScO 3 , DyScO 3 and HfTiO 4 . Qualitative and quantitative differences are identified between dipole allowed intra-atomic transitions from core p-states to empty d*-and s*-states, and inter-atomic transitions from transition metal and oxide 1s states to O 2p* that are mixed with transition metal d*-and s*-states for transition metal oxides and silicate alloys. The complex oxide studies have focused on the O K 1 edge spectra. Differences between the spectral peak energies of the lowest d*-features in the respective O K 1 spectra are demonstrated to scale with optical band gap differences for TiO 2 , ZrO 2 and HfO 2 , as well as the complex oxides providing important information relevant to applications of TM oxides as high-k gate dielectrics in advanced Si devices. This is demonstrated through scaling relationships between (i) conduction band offset energies between Si and the respective dielectrics, and the optical band gaps, and (ii) the optical band gaps, the conduction band offset energies, and the electron tunneling masses as functions of the atomic d-state energies of the transition metal atoms.

show abstract

“…[8] and [9] [10,11], and (ii) a specification of the chemical bonding self-organizations that give the IPs their interesting and unique properties, e.g., minimal strain, and low defect densities. The nano-scale for this CBSOs has been estimated from CBSOs that take place in Zr and Hf silicate thin films [12,13]. Combined with the percolation theory criteria in Refs.…”

Section: Semi-empirical Bond Constraint Theorymentioning

confidence: 99%

“…The basis for the model developed in this article derives from chemical phase separations (CPS), or equivalently CBSOs, reported for Zr and Hf silicate alloys [12,13]. Predominantly ionic Zr-O and Hf-O bonds and +4 formal valence states of Zr and Hf result in a significant disruption of the SiO 2 continuous random network.…”

Section: Chemical Bonding Self-organizationsmentioning

confidence: 99%

Chemical Bonding Self-Organizations and Percolation Theory Applied to Minimization of Macroscopic Strain: Internal Interfaces in Non-Crystalline and Nano-Crystalline Thin Films

Lucovsky

Phillips

2009

e-J. Surf. Sci. Nanotechnol.

View full text Add to dashboard Cite

Integration of non-crystalline and nanocrystalline thin films and nanocrystalline/non-crystalline composites in devices generally requires isotropic properties, and minimization of macroscopic strain. A novel pathway for obtaining isotropic properties and strain reductions is identified. The microscopic mechanism is based on nanoscale chemical bonding self organizations such as those that occur in intermediate phases, IPs, of non-crystalline glasses and thin films. This article emphasizes the importance on internal interfacial properties and the critical role they play. This understanding has emerged from studies on qualitatively different thin film materials, such as (i) As-Se thin film photoreceptors for electro-photographic applications, (ii) thin film transistor dielectrics for liquid crystal displays, (iii) high-k replacement dielectrics for SiO2 in aggressively-scaled field effect transistors, and (iv) passive thin films for optically switched memory cells.

show abstract

Spectroscopic study of chemical phase separation in zirconium silicate alloys

Cited by 68 publications

References 11 publications

High dielectric constant oxides

High dielectric constant oxides

Spectroscopic studies of metal high‐k dielectrics: transition metal oxides and silicates, and complex rare earth/transition metal oxides

Chemical Bonding Self-Organizations and Percolation Theory Applied to Minimization of Macroscopic Strain: Internal Interfaces in Non-Crystalline and Nano-Crystalline Thin Films

Contact Info

Product

Resources

About