In this paper, results for dielectric oxide films deposited using downstream microwave plasma-enhanced chemical vapor deposition in the temperature range between 250 and 400 °C are presented. The deposition of oxide using TEOS (tetraethoxysilane)+O2 and TEOS+N2O chemistries are studied. In the reactor, the TEOS is injected directly into the deposition chamber without passing through the discharge. Only He, O2, or N2O are fed through the microwave cavity where the discharge is generated. In addition, no ions but chemically active species are present in the deposition chamber during the deposition. The deposition rate is found to decrease with increasing temperature. In addition, it appears that the deposition rate increases with increasing concentration of active oxygen species in the deposition chamber. These suggest that the generation of intermediate species of TEOS and adsorption/desorption of the reactant on the surface are the key steps that determine the deposition rate. The stress of the deposited oxide films is found to be tensile and less than 2×109 dyn/cm2. The Si-OH concentration in the films is found to be low and can be below the detection limit of infrared spectrometry by increasing the flow ratio of O2/TEOS during the deposition. The step coverage of the oxide films over the Al runners is found to be excellent due to the long diffusion time available for TEOS surface species before forming SiO2. The mechanisms of oxide deposition using TEOS+O2 and SiH4+N2O chemistries are studied and compared. The details of oxide step coverage versus different deposition processes are also discussed.

Carbohydrate–lectin recognition plays important roles in cell–cell communication, proliferation, and differentiation. We report here a new approach of using a carbohydrate‐encapsulated gold nanoparticle (shown in purple) as an affinity probe for the efficient separation and enrichment of target proteins, and then protein identification and epitope mapping by MALDI‐TOF MS.

We have compared the step coverage of plasma enhanced chemical vapor deposition tetraethylorthosilicate films of microwave downstream, high frequency radio frequency (rf), and low frequency rf depositions. The microwave-downstream deposition, characterized by bimolecular surface reactions, produces a conformal step coverage. The rf depositions with ion-induced surface reactions produce a low sidewall, high bottom coverage. The chemical radical and the ion effects on the step coverage are discussed.

Development of a rapid, effective, and highly specific platform for target identification in complex biofluids is one of the most important tasks in proteomic research. Taking advantage of the natural hydrophobic interaction of PVDF with probe protein, a simple and effective method was developed for protein quantitation and profiling. Using antibody-antigen interactions as a proof-of-concept system, the targeted plasma proteins, serum amyloid P (SAP), serum amyloid A (SAA), and C-reactive protein (CRP), could be selectively isolated and enriched from human plasma by antibody-immobilized PVDF membrane and directly identified by MALDI-TOF MS without additional elution step. The approach was successfully applied to human plasma for rapid quantitation and variant screening of SAP, SAA, and CRP in healthy individuals and patients with gastric cancer. The triplexed on-probe quantitative analysis revealed significant overexpression of CRP and SAA in gastric cancer group, consistent with parallel ELISA measurements and pathological progression and prognostic significance reported in previous literatures. Furthermore, the variant mass profiling of the post-translationally modified forms revealed a high occurrence of de-sialic acid SAP in patients with gastric cancer. Due to the versatile assay design, ease of probe preparation without chemical synthesis, and compatibility with MALDI-TOF MS analysis, the methodology may be useful for target protein characterization, functional proteomics, and screening in clinical proteomics.

Despite stringent power consumption requirements in many applications, over years organic light‐emitting diode (OLED) displays still suffer unsatisfactory energy efficiency due to poor light extraction. Approaches have been reported for OLED light out‐coupling, but they in general are not applicable for OLED displays due to difficulties in display image quality and fabrication complexity and compatibility. Thus to date, an effective and feasible light extraction technique that can boost efficiencies and yet keep image quality is still lacking and remains a great challenge. Here, a highly effective and scalable extraction‐enhancing OLED display pixel structure is proposed based on embedding the OLED inside a three‐dimensional reflective concave structure covered with a patterned high‐index filler. It can couple as much internal emission as possible into the filler region and then redirect otherwise confined light for out‐coupling. Comprehensive multi‐scale optical simulation validates that ultimately high light extraction efficiency approaching ≈80% and excellent viewing characteristics are simultaneously achievable with optimized structures using highly transparent top electrodes. This scheme is scalable and wavelength insensitive, and generally applicable to all red, green, and blue pixels in high‐resolution full‐color displays. Results of this work are believed to shed light on the development of future generations of advanced OLED displays.

The transition from a planar to a FinFET device structure has changed device doping requirements. The fin sidewall doping and activation, crystallinity control of the fin, junction profile and leakage control on the fin are new challenges. With continuous scaling of FinFET technology, the narrower fins become more prone to crystallinity damage by ion implant, and lead to increases in junction leakage and fin parasitic resistance. We have introduced hot implant as a superior doping technique to room-temperature implant for arsenic source drain extension (SDE) and halo implants on vertical narrow fins. We have demonstrated for the first time that hot SDE implant on 6nm CD vertical fins produced single crystalline fins and enabled 5x improvement in fin line resistance and more than 10x reduction in junction leakage compared with a room-temperature SDE implant.

We have developed a low-temperature (≲300 °C) plasma deposition process to prepare novel fluorine-containing silicon nitride films (p-SiN:F) using SiH4–NF3–N2 discharge mixtures at 14 MHz rf applied frequency. The deposition rate can be extremely high, up to 1600 Å/min. Data indicate p-SiN:F has electrical properties (dielectric constant, breakdown strength, resistivity, etc.) which compare favorably to high-temperature, chemical-vapor-deposited silicon nitride. By controlling the feed chemistry and physical variables of the discharge, a wide variety of film compositions are achieved. Moreover, this chemistry is superior to the only other p-SiN:F which was prepared from a SiF2/SiF4-H2-N2 feed. Two classes of films were identified as stable or unstable to air exposure and the instability of the films correlated with the atom fraction of fluorine initially incorporated. Infrared, Auger electron, and Rutherford backscattering spectroscopy measurements show that low hydrogen concentrations are produced by the introduction of fluorine in the silicon nitride films. More importantly, the concentration of Si–H is extremely low because strong Si–F bonding replaces the weak Si–H bonds that satisfy free Si orbitals found in conventional plasma nitride, and the hydrogen remaining in the film is present as stable N–H bonds. We believe this substitution of silicon-bound hydrogen, caused by the gas phase and surface-driven reactions, is a source of superior film properties. The mechanism for this novel discharge chemistry is discussed.

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