International Technology Roadmap for Semiconductors 2003の要求清浄度について － シリコンウエハ表面と雰囲気環境に要求される清浄度, 分析方法の現状について －

http://depts.washington.edu/solgel/documents/pub_docs/journal_docs/2011/Nanostructured%20carbon%20for%20energy%20storage%20and%20conversion.pdf

Nanostructured carbon for energy storage and conversion

Review of physical vapor deposited (PVD) spectrally selective coatings for mid- and high-temperature solar thermal applications

Thin films are formed by formed by atomic layer deposition, whereby the composition of the film can be varied from monolayer to monolayer during cycles (301) or (450, 455, 460, 470) including alternating pulses of self-limiting chemistries. In the illustrated embodiments, varying amounts of impurity sources (306 or 460) are introduced during the cyclical process. A graded gate dielectric (72) is thereby provided, even for extremely thin layers. The gate dielectric (72) as thin as 2 nm can be varied from pure silicon oxide to oxynitride to silicon nitride. Similarly, the gate dielectric (72) can be varied from aluminum oxide to mixtures of aluminum oxide and a higher dielectric material (e.g., ZrO2) to pure high k material and back to aluminum oxide. In another embodiment, metal nitride (432) (e.g., WN) is first formed as a barrier for lining dual damascene trenches and vias. During the alternating deposition process, copper can be introduced, e.g., in separate pulses, and the copper source pulses (460) can gradually increase in frequency, forming a graded transition region (434), until pure copper (436) is formed at the upper surface. Advantageously, graded compositions in these and a variety of other contexts help to avoid such problems as etch rate control, electromigration and non-ohmic electrical contact that can occur at sharp material interfaces.

Graded thin films

A high k dielectric film and methods for forming the same are disclosed. The high k material includes two peaks of impurity concentration, particularly nitrogen, such as at a lower interface and upper interface, making the layer particularly suitable for transistor gate dielectric applications. The methods of formation include low temperature processes, particularly CVD using a remote plasma generator and atomic layer deposition using selective incorporation of nitrogen in the cyclic process. Advantageously, nitrogen levels are tailored during the deposition process and temperatures are low enough to avoid interdiffusion and allow maintenance of the desired impurity profile.

Incorporation of nitrogen into high k dielectric film

The effect of rapid thermal annealing processes on the properties of SiO2.0 and SiN1.55 films was studied. The films were deposited at room temperature from N2 and SiH4 gas mixtures, and N2, O2, and SiH4 gas mixtures, respectively, using the electron cyclotron resonance technique. The films were characterized by Fourier transform infrared spectroscopy (FTIR) and electron paramagnetic resonance spectroscopy. According to the FTIR characterization, the SiO2.0 films show continuous stress relaxation for annealing temperatures between 600 and 1000 °C. The properties of the films annealed at 900–1000 °C are comparable to those of thermally grown ones. The density of defects shows a minimum value for annealing temperatures around 300–400 °C, which is tentatively attributed to the passivation of the well-known E′ center Si dangling bonds due to the formation of Si–H bonds. A very low density of defects (5×1016 cm−3) is observed over the whole annealing temperature range. For the SiN1.55 films, the highest struct...

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Rapid thermal annealing effects on the structural properties and density of defects in SiO2 and SiNx:H films deposited by electron cyclotron resonance

Full composition range silicon oxynitride films deposited by ECR-PECVD at room temperature

We have analyzed the structural and optical properties of Si implanted with very high Ti doses and subsequently pulsed-laser melted (PLM). After PLM, all samples exhibit an abrupt and roughly uniform, box-shaped Ti profile, with a concentration around 2 × 1020 cm−3, which is well above the Mott limit, within a 150 nm thick layer. Samples PLM-annealed at the highest energy density (1.8 J/cm2) exhibit good lattice reconstruction. Independent of the annealing energy density, in all of the samples we observe strong sub-bandgap absorption, with absorption coefficient values between 4 × 103 and 104 cm−1. These results are explained in terms of the formation of an intermediate band (IB) originated from the Ti deep levels.

/pdf/sub-bandgap-absorption-in-ti-implanted-si-over-the-mott-1jv6ojnmfp.pdf

Sub-bandgap absorption in Ti implanted Si over the Mott limit

We report room-temperature operation of 1 × 1 cm2 infrared photoconductive photodetectors based on silicon supersaturated with titanium. We have fabricated these Si-based infrared photodetectors devices by means of ion implantation followed by a pulsed laser melting process. A high sub-band gap responsivity of 34 mV W−1 has been obtained operating at the useful telecommunication applications wavelength of 1.55 μm (0.8 eV). The sub-band gap responsivity shows a cut-off frequency as high as 1.9 kHz. These Si-based devices exhibit a non-previous reported specific detectivity of 1.7 × 104 cm Hz1/2 W−1 at 660 Hz, under a 1.55 μm wavelength light. This work shows the potential of Ti supersaturated Si as a fully CMOS-compatible material for the infrared photodetection technology.

/pdf/room-temperature-operation-of-a-titanium-supersaturated-3mf5f4j2mw.pdf

Room-temperature operation of a titanium supersaturated silicon-based infrared photodetector

Hydrogen and nitrogen release processes in amorphous silicon nitride dielectrics have been studied by MeV ion scattering spectrometry in combination with infrared spectroscopy. The outdiffusion of those light constituents was activated by the thermal energy supplied to the samples by rapid thermal annealing treatments. Molecular models of how these reactions proceed have been proposed based on the information obtained from the infrared spectra, and the validity of the models has been tested by an analysis of the activation energy of the desorption processes. For this purpose, the evolution of the hydrogen concentration versus the annealing temperature was fitted to an Arrhenius-type law obtained from a second-order kinetics formulation of the reactions that are described by the proposed structural models. It was found that the low values of the activation, energies can be consistently explained by the formation of hydrogen bonding interactions between Si-H or N-H groups and nearby doubly occupied nitrogen orbitals. This electrostatic interaction debilitates the Si-H or N-H bond and favors the release of hydrogen. The detailed mechanism of this process and the temperature range in which it takes place depend on the amount and the proportion of hydrogen in SI-H and N-H bonds. Samples with higher nitrogen content, in which all bonded hydrogen is in the form of N-H bonds, are more stable upon annealing than samples in which both Si-H and N-H bonds are detected. in those nitrogen-rich films only a loss of hydrogen is detected at the highest annealing temperatures.

/pdf/molecular-models-and-activation-energies-for-bonding-4qq7mbi352.pdf

Molecular models and activation energies for bonding rearrangement in plasma-deposited a − SiN x : H dielectric thin films treated by rapid thermal annealing

A. del Prado

Papers

Rapid thermal annealing effects on the structural properties and density of defects in SiO2 and SiNx:H films deposited by electron cyclotron resonance

Full composition range silicon oxynitride films deposited by ECR-PECVD at room temperature

Sub-bandgap absorption in Ti implanted Si over the Mott limit

Room-temperature operation of a titanium supersaturated silicon-based infrared photodetector

Molecular models and activation energies for bonding rearrangement in plasma-deposited a − SiN x : H dielectric thin films treated by rapid thermal annealing