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A study was conducted to examine the [Si.sub.3][N.sub.4]/Zr[O.sub.2] split charge trapping layer (SCTL) by multibit-cell Flash memory using Fowler-Nordheim (F-N) method. Findings reveal that the 2-bit (2-b) charge storage is accomplished by physical data node separation for the SCTL rather than charge injection control.

A study was conducted to examine the program and retention transients of silicon nitride-based (SONOS/TANOS) nonvolatile memories using a new characterization technique and an improved model for charge injection and transport through ONO gate stacks. Results reveal that the carrier transport in the SiN layer affects the spatial distribution of the trapped charge and various aspects of program and retention transients.

Fin silicon-oxide-nitride-oxide-semiconductor (SONOS) Flash memories having independent double gates are prepared and this device has two sidewall gates sharing one Si fin. Specific fabrication processes are described for the fin SONOS Flash memory having independent double gates and electrical properties related to the opposite gate dependence are analyzed.

A new silicon-nitride-based wafer bonding process, which can be used for the fabrication of capacitive micromachined ultrasonic transducers (CMUTs), is presented. The process is shown to be extremely beneficial, as it is small and cost-effective and also improves the active area of the system.

A phenomenological method is used for isolating the hole-trapping and interface trap generation components during negative bias temperature instability (NBTI) stress in plasma nitrided oxide (PNO) p-MOSFETs. The robustness and uniqueness of the separation procedure of the isolation technique is demonstrated by degradation data obtained from a wide range of operating conditions and a wide variety of PNO processes.

Silicon nitride films of different refractive indices are used to study the effect of hydrogenation of ZnO TFTs by plasma-deposited silicon nitride gate dielectric. Secondary ion mass spectroscopy study show that in ZnO TFT using high refractive index silicon nitride, gate dielectric is higher that TFTs with low-refractive index silicon nitride, which is indicative of the hydrogenation of ZnO TFTs by high refractive index silicon nitride gate dielectric.

The dependence of the tunneling effective mass of electrons on gate dielectric nitrogen concentration and thickness in MOSFETs with lightly doped silicon oxynitride (Si[O.sub.x][N.sub.y]) gates is studied. The results have shown a strong dependence of the effective mass on the sample thicknesses and nitrogen concentration, where the electron effective mass has increased with the decrease in the thickness and the higher nitrogen concentration has caused a reduction in effective mass.

The polycrystalline silicon with regular square grains is fabricated by using metallic periodic pads as the heat sinks and with underlying silicon oxynitride (SiON) as the heat absorption layer. The studies have shown that the thin-film transistor with smaller channel width and length has resulted in a better subthreshold swing because it contains fewer grain boundaries and defects.

A new approach to the local measurement of residual stress in microstructures is described in this paper. The presented technique takes advantage of the combined milling-imaging features of a focused ion beam (FIB) equipment to scale down the widely known hole drilling method. This method consists of drilling a small hole in a solid with inherent residual stresses and measuring the strains/displacements caused by the local stress release, that takes place around the hole. In the presented case, the displacements caused by the milling are determined by applying digital image correlation (DIC) techniques to high resolution micrographs taken before and after the milling process. The residual stress value is then obtained by fitting the measured displacements to the analytical solution of the displacement fields. The feasibility of this approach has been demonstrated on a micromachined silicon nitride membrane showing that this method has high potential for applications in the field of mechanical characterization of micro/nano-electromechanical systems. [1634] Index Terms--Microreliability, residual stress.

A study was conducted about degradation of pMOSFETs under negative gate bias stress to determine the macroscopic and phenomenological similarity between stress-induced leakage current (SILC) and negative bias temperature instability (NBTI). Results reveal that SILC and NBTI in pMOS are not linked directly at least from the microscopic perspective despite their macroscopic similarity.

A new high-performance stable [Ir.sub.x]Si full silicidation (FUSI) gate is proposed on high-[kappa] HfSiON. The 1000 degree Celsius thermal stability above pure metal is found to be due to the inserted 5-nm amorphous Si, which has provided less Fermi-level pinning by the accumulated metallic full silicidation at the interface.

A study was conducted to examine the influence of Ni enrichment of the gate electrode on the equivalent oxide thickness (EOT), time dependent dielectric breakdown (TDDB) reliability, and bias temperature instability (BTI) of n/p-FETs. The positive BTI of the n-FETs was negligible and was not degraded by Ni enrichment of the gate electrode and additional annealing, suggesting that HfSiON was stable against the Ni-full-silicide process.

The fabrication and characterization of bottom-gate and top-gate nanocrystalline silicon (nc:Si:H) thin-film transistors (TFTs) with amorphous-silicon nitride (a-Si[N.sub.x]:H) as the gate dielectric is reported. The nc-Si:H TFTs have shown much better threshold-voltage ([V.sub.T]) stability when compared to amorphous-silicon (a-Si:H) counterparts, thereby offering great promise for applications in active-matrix organic light-emitting diode (AMOLED) displays.

The effect of oxidation on the chemical bonding structures of silicon nitride thin films synthesized by a low-temperature plasma-enhanced chemical vapor deposition (PECVD) method is investigated. The crystalline silicon dioxide is found to be stoichiometric Si[O.sub.2], whereas the remaining matrix is found to be a nonstoichiometric silicon oxynitride conforming to the random bonding model.

The characterization of mixed-signal and noise properties of MOSFETs with Hf-based high-[kappa] gate dielectrics and TaN metal gates is presented. The optimization of both devices, such as channel doping engineering and high-[kappa] gate stack properties, is required to meet expectations on improvements of analog performance of low-power (LP) CMOS devices.

Positive bias temperature instability (PBTI) recovery transient method is described to investigate trap properties in HfSiON as high-[kappa] gate dielectric in nMOSFETs. An analytical model based on thermally assisted tunneling can reproduce measured transient characteristics and the proposed technique for single-charge effect characterization provides insight into trap properties in high-[kappa] gate dielectrics in nanoscale CMOS device development.

A diffusion path of water (H2O) from silicon dioxide (SiO2) to the channel surface and its influence on the transistor's hump are investigated. It is observed that the major path of H2O diffusion is gate edges, especially along the gate to drain/source overlap region, and thus, decreases in channel width induces more leakage current than channel length.

Stress in low-temperature plasma-enhanced chemical vapor deposited silicon nitride (SiN(sub x)) thin films subject to cryogenic thermal cycling (100-323 K) are measured. The stress state of SiN(sub x) films deposited below 150 degree Celsius is stable under atmospheric conditions, in contrast to SiN(sub x) films deposited below 100 degree Celsius, which under atmospheric conditions become more tensile with time due to oxidation.

A low-frequency noise characteristic is reported for TASiN-gated n-channel MOSFETs with atomic-layer deposited HfO(sub 2) on thermal SiO(sub 2) with stress-relieved preoxide (SRPO) pretreatment. The normalized noise spectral density values for the control devices are found to be lower when compared to reference poly Si gate stack with similar HfO(sub 2) dielectric.

An investigation is conducted on the optical and electrical properties of Nb2Si(sub y)N(sub x) thin films deposited by dc reactive magnetron sputtering as a function of the Si content (C(sub Si). The optical properties were studied by both specular reflectivity and spectroscopic ellipsometry.

A report is presented on the growth of and evolution of defects in GaN epilayers having single- and double-layer SiN(sub x) nanoporous insertion layers. The SiN(sub x) was formed in situ in the growth chamber of an organometallic vapor-phase epitaxy system by simultaneous flow of diluted silane and ammonia.

An AlGaN/GaN high electron mobility transistor with a Si3N4 passivation layer is prepared that is deposited in situ in metal-organic chemical-vapor deposition reactor in the same growth sequence, as the rest of the layer stack. The SiN4 is shown to be of high quality and stoichiometric in composition.

An overview of the integration of the hot-electron bolometers (HEB) array chip with silicon micromachined backshorts and feedhorns are provided and material issues surrounding the device fabrication is explained. The resistance and I-V measurements are reported and the HEBs fabricated on silicon nitride to similar devices on quartz substrates are compared.

Solid-state refrigerators based on normal metal/insulator/superconductor (NIS) tunnel junctions are used to demonstrate the cooling of the electrons and phonons of silicon nitride (Si-N) membranes. A temperature reduction of the Si-N membrane from 260 mK to 240 mK is reported and mechanism for cooling an isolated membrane is explained.

A fabrication process for membrane-structured superconducting MgB2 neutron detectors and measurement of their dc-characteristics is reported. The membrane-structured MgB2 device showed superconductivity, namely, a T(sub c, onset) of 28.2 K, a T(sub c, offset) of 27.3 K, and an RRR of 1.18.

A unique, band-engineered, configuration of the charge-trapping layer in silicon-oxide-nitride-oxide-silicon (SONOS) devices is proposed for high-density Flash memory applications. A varying Si-N in modified silicon nitride is obtained by controlling reaction gas flow-rate during deposition.

ZrO2 thin films are deposited by atomic-layer deposition (ALD) using zirconium tertiary-butoxide [Zr(t-OC4H9)4, (ZTB)] and H2O source gases on Si substrates at low temperatures. The study shows that the conduction mechanism was identified as direct tunneling of electron except at very low dielectric fields.

Comparative surface evolution of nanocrystalline (nc)-CrN and amorphous (a)-Si3N4 monolithic films and their alternative multilayer films have been discussed in relation to film thickness in monolithic films, as well as to modulation periods in multilayers. The resulting parameters are discussed in terms of three competitive factors: surface diffusion, shadowing, and oriented growth, and are compared with results of previous experimental and theoretical studies.

High density Si nanoparticles have been successfully grow on Si(sub 3)N(sub 4) and SiO(sub 2) thin films by hot wire chemical vapor deposition using disilane, in which Si atoms are generated on a heated tungsten filament and, after desorbing, impinge on the substrate. Parallel thermal chemical vapor deposition broadens the size distribution of Si nanoparticles and causes coalescence of neighboring nanoparticles, leading to a decrease of nanoparticle density.

One-color resonant and nonresonant ionization studies of Si2N and Si2O are performed using a pulsed laser vaporization cluster source in conjunction with a time-of-flight mass spectrometer. The ionization potential of Si2N is established as less than 6.4 eV, while the ionization potential of Si2O is bracketed between 6.4 and 7.9 eV.

The microstructures of TiN/SiN(sub x) films were studies by means of a Monte Carlo method. The findings show that the average size of TiN grains decreases with volume fraction of SiN(sub x) approximately according to a power law with a time-dependent exponent decreasing with growth time.

The interplay observed between the metal nanoparticles and dielectric spacing layers during the growth of the granular Au/[Si.sub.3][N.sub.4] multilayers grown by vapor deposition method is analyzed. An increase in the thickness of the deposited Au per bilayer in the system is shown to lead to a significant enhancement in its crystalline order.

The laser ablation of Si[N.sub.x] layers on planar and textured silicon surfaces for various laser wavelengths and pulse durations in the nanosecond (ns) to femtosecond (fs) range is examined. The results have shown that on alkaline textured surfaces the ablation by an ns laser has produced less damage than by an ultrashort pulse laser.

The article explains the structures and the magnetic and tribological properties of the various Fe-Si-N films deposited by the reactive magnetron cosputtering technique. The films are shown to exhibit extremely high mechanical hardness and hence can be used as magnetic overcoat for the high density recording disk drives.

Nanopores fabricated in silicon nitride membranes and highly sensitive electrical recordings are used for showing single-molecule observation of nonspecific protein adsorption onto an inorganic surface. Single-molecule electrical signatures have shown that the bindings of bovine serum albumin (BSA) to the nitride surface have occurred in two distinct orientations.

The article explains the various properties of the thin silicon dioxide films that are deposited on the different nanomechanical silicon nitride resonators via the atomic layer deposition technique. The quality factors are shown to considerably reduce with the deposition of the thicker films.