The electrical measurement has demonstrated that conductivity of CaO-doped CeO2 has higher activation energy for low temperature and lower activation energy for high temperature. A model with two different kinds of defect interactions between oxygen vacancy and doped cations has been used to interpret the phenomenon. Diffusion based on hopping of oxygen ions was assumed as the mechanism of electrical conduction. The analysis indicated that at high temperature free oxygen vacancies are dominant and the activation energy is only for oxygen ion hopping. At low temperature, however, oxygen vacancies associated with dopant calcium ions are dominant for high CaO content and the activation energy is the energy for hopping of an oxygen ion plus half of the association energy between one oxygen vacancy and one calcium ion. For low level doping, both free and associated oxygen vacancies are important.

Plasma ion implantation (PII) doping processes utilizing PH3/He and B2H6/He plasmas to fabricate CMOS devices are presented. The impact of plasma chemistry of PH on device structure and characteristics are studied. By using an optimized process condition, low contamination levels and good device characteristics have been achieved.

Plasma ion implantation (PII) doping technique has been utilized to prepare a new lowdielectric constant (low k) material SiO(F,C). Fluorine and carbon were implanted into SiO2 films by CF4 PII using an ICP plasma reactor. The effective dielectric constant of the films was significantly reduced after PH doping. An analysis of a double layer model indicated that a high quality dielectric layer with a dielectric constant down to 2.8 can be achieved by an optimized PII process. Contrasting to other conventional low-k material techniques, PII process also improved bulk resistivity and electrical field breakdown strength. The improvement possibly resulted from adding carbon into the films. The etching effect of CF4 PII could be beneficial to planarization and gap filling of dielectric interlayer.

Development of ion doping and hydrogenation equipment using plasma ion implantation (PII) is being studied. It is shown that low energy, high throughput operation could eliminate problems associated with etching, charging, cooling, and contamination. The applications of a new plasma source and neural network implementation optimization are also reported.

A plasma immersion ion implantation (PIII) hydrogenation process using an inductively-coupled plasma (ICP) source is implemented for defect passivation in polycrystalline silicon (poly-Si) thin film transistors (TFT's). Device parameter improvement saturates in 4 minutes, which is considerably shorter than for other reported hydrogenation methods. Stress test indicates that the devices hydrogenated by this novel technique have much better long-term reliability. The hydrogenation effects on two types of trap states are analyzed the current-voltage characteristics of the devices. The densities of deep states and tail states are significantly reduced after short time hydrogenation.

The use of plasma immersion ion implantation (PIII) as a novel method for the treatment of polymer surfaces is investigated. The effect of PIII treatment on the coefficient of friction, contact angle modification, and surface energy of silicone and EPDM (ethylene-propylene-diene monomer) rubber are investigated as a function of pulse voltage, treatment time, and gas species. Low energy (0 - 8 keV) and high dose (∼1017 - 1018 ions/cm2) implantation of N2, Ar, and CF4 is performed using an inductively coupled plasma source (ICP) at low pressure (0.2 mTorr). PIII treatment reduces the coefficient of friction (μ) of silicone rubber from μ = 0.464 to the range μ = 0.176 – 0.274, and μ of EPDM rubber decreases from 0.9 to the range μ = 0.27 – 0.416 depending on processing conditions. The contact angle of water and diiodomethylene decreases after implantation and increases at higher doses for both silicone and EPDM rubber.

A plasma immersion ion implantation (Pill) hydrogenation process using an inductively-coupled plasma (ICP) source is implemented for defect passivation in polycrystalline silicon (poly-Si) thin film transistors (TFT's). Device parameter improvement saturates in 4 minutes, which is considerably shorter than for other reported hydrogenation methods. Stress test indicates that the devices hydrogenated by this novel technique have much better long-term reliability. The hydrogenation effects on two types of trap states are analyzed the current-voltage characteristics of the devices. The densities of deep states and tail states are significantly reduced after short time hydrogenation.

PH3 SDS (safe delivery system) gas was used for the first time in P11 doping experiments to fabricate n+p junctions and NMOS devices. Two gas recipes (PH3 diluted in H2 and He) were investigated. Under lower pressure, a minimum etching effect was observed. A 4x1015/cm2 phosphorus dose and a 22 Ω/□ sheet resistance were achieved in 4 seconds. Very low contamination level was involved. An anomalous tail of P profile in Si substrate was observed using SIMS measurements.

Plasma ion implantation (PII) hydrogenation has been developed for defect passivation in polycrystalline silicon (poly-Si) thin film transistors (TFTs). A high dose rate PII process using a microwave multipolar bucket (MMB) plasma source and a 12.5 kHz pulse generator achieves saturation of device parameter improvement in 5 minutes, which is much shorter than other hydrogenation methods investigated thus far. These results have been achieved in one sixth the implant time of our previous PII experiments and are in good agreement with our process simulation.

Amorphous carbon films (a-C) deposited by the anodic vacuum arc on Si substrates were implanted with nitrogen using the Plasma Immersion Ion Implantation (PIII) technique to form carbon nitride films (CNX). Scanning Electron Microscopy (SEM) of the a-C films show a surface morphology with maximum grain size in the order of a few nanometers and the exclusion of macroparticles. INcreasing the nitrogen content of the CNX films increased the intensity of the X-ray Photoelecton Spectroscopy (XPS) C Is peak at 286.6 eV and formed a new peak at 285.6 eV which both can be associated with the carbon-nitrogen bond formation. Nanoindentaiton measurements showed that the hardness of the a-C films increased after implanting nitrogen into them. these CNX films exhibited a hardness of 19 GP A.

Carbon nitride (CNX) films were prepared by nitrogen ion implantation into carbon films (a-C) deposited on Si substrates by the anodic vacuum arc. Plasma Immersion Ion Implantation (PIII) and Ion Beam (IB) implantation methods were used. X-ray Photoelectron Spectroscopy (XPS) C Is and N Is spectra of all CNX films indicate the formation of carbon-nitrogen bonds. The bonds are associated with the C 1s peaks at 286.6 eV and 285.6 eV , and the N 1s peaks at 399.1 eV and 400.6 eV. Raman spectra show that the structure of the implanted films (CNX) becomes more amorphous as the two broad peaks at 1577 cm-1 (G line) and 1350 cm-1 (D line) observed in the a-C films disappear and a broad asymmetric peak around 1500 cm-1 is formed. The interfacial tension between the a-C films and the substrate , obtained from the contact angle measurements, decreased by more than half after nitrogen implantation.