Embodiments of the invention provide methods for depositing a capping layer on a dielectric layer disposed on a substrate. In one example, a process includes exposing a substrate to a deposition process to form a dielectric layer thereon, exposing the substrate to sequential pulses of a silicon precursor and an oxidizing gas to form a silicon-containing layer on the dielectric layer during a deposition process, exposing the substrate to a nitridation process to form a capping layer thereon and exposing the substrate to an annealing process for a predetermined time. The capping layer may a thickness of about 5 A or less. In one example, the oxidizing gas contains water vapor derived from a hydrogen source gas and an oxygen source gas processed by a water vapor generator containing a catalyst. In another example, the deposition, nitridation and annealing processes occur in the same process chamber.

Formation of a silicon oxynitride layer on a high-k dielectric material

Embodiments of the invention provide methods for forming hafnium materials, such as oxides and nitrides, by sequentially exposing a substrate to hafnium precursors and active oxygen or nitrogen species (e.g., ozone, oxygen radicals, or nitrogen radicals). The deposited hafnium materials have significantly improved uniformity when deposited by these atomic layer deposition (ALD) processes. In one embodiment, an ALD chamber contains an expanding channel having a bottom surface that is sized and shaped to substantially cover a substrate positioned on a substrate pedestal. During an ALD process for forming hafnium materials, process gases form a vortex flow pattern while passing through the expanding channel and sweep across the substrate surface. The substrate is sequentially exposed to chemical precursors that are pulsed into the process chamber having the vortex flow.

Ald metal oxide deposition process using direct oxidation

Plasma-assisted oxidation, anodization, and nitridation of silicon have been performed in microwave, rf, and dc plasmas with a variety of reactor configurations and a range of plasma densities. Compared to thermal processes at equivalent substrate temperatures, film growth rates are accelerated by the plasma-enhanced generation of reactive chemical species or by the presence of electric fields to aid charged-particle transport during plasma processes. Oxidation, anodization, and nitridation kinetics, mechanisms, and film properties attainable with plasma enhancement are discussed for crystalline, polycrystalline, and amorphous silicon layers and for silicon-germanium alloys. The use of these plasma methods for surface and interface modification of silicon-based materials and devices is described.

Plasma-assisted oxidation, anodization, and nitridation of silicon

Results of an in situ X-ray scattering study of the passive film formed on Ni(111) electrodes by passivation in 0.05 M H2SO4 (pH 1.0) at 0.50 VAg/AgCl are reported and compared with results on the film formed by oxidation in air at room temperature. In both cases, ultrathin, (111)-oriented NiO films are observed, which are aligned with the Ni substrate lattice and slightly expanded along the surface normal with respect to bulk NiO. However, two major structural differences are found:  (i) while on the air-formed oxide parallel (NiO[110] || Ni[110]) and antiparallel (NiO[110] || Ni[110]) oriented domains coexist, the passive film exhibits a well-defined antiparallel orientation and (ii) the lattice of the passive film is, in contrast to that of the air-fomed oxide, tilted relative to the substrate with a broad angular dispersion of the tilt angle centered at about 3.3°.

In Situ X-ray Scattering Study of the Passive Film on Ni(111) in Sulfuric Acid Solution

The present invention generally provides methods and apparatuses that are adapted to form a high quality dielectric gate layer on a substrate. Embodiments contemplate a method wherein a metal plasma treatment process is used in lieu of a standard nitridization process to form a high dielectric constant layer on a substrate. Embodiments further contemplate an apparatus adapted to “implant” metal ions of relatively low energy in order to reduce ion bombardment damage to the gate dielectric layer, such as a silicon dioxide layer and to avoid incorporation of the metal atoms into the underlying silicon. In general, the process includes the steps of forming a high-k dielectric and then terminating the surface of the deposited high-k material to form a good interface between the gate electrode and the high-k dielectric material. Embodiments of the invention also provide a cluster tool that is adapted to form a high-k dielectric material, terminate the surface of the high-k dielectric material, perform any desirable post treatment steps, and form the polysilicon and/or metal gate layers.

Method and apparatus for fabricating a high dielectric constant transistor gate using a low energy plasma system

The anodization of Si in a 1 MHz oxygen plasma is described. In‐situ film thickness measurements were made using a single angle "s" light reflectance technique and this data, coupled with information on the variation of sample voltage with thickness, was used to determine the dependence of ionic current on oxide field strength. The data for a given oxide thickness could be described by an equation of the form given by the theory of ionic conduction by a thermally activated, field‐assisted process. However, the ionic current and, in paticular, the oxide field strength were dependent on oxide thickness. MOS C‐V measurements on oxides of different thickness indicated a change in flatband voltage that could be attributed to a progressive build‐up of positive charge within the oxide. This space charge could be reduced by a low temperature annealing treatment. The oxides were found to be slightly absorbing optically, to have a relative permittivity in the range 3.5–3.9, and to possess good insulation properties as long as the oxide thickness did not exceed about 2500â.

D. L. Pulfrey

Papers

The Anodization of Si in an RF Plasma

The anodization of si in an rf plasma