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Broadband optical monitoring for thin-film filter manufacturing is more and more developed thanks to better performances of spectrometers with array detectors. We compare this optical monitoring with turning point monitoring and quartz monitoring of different designs. The sensitivity to thickness errors and to refractive index errors is evaluated. We show that real time determination of deposited thickness is a valuable criterion. We also present our experimental setup of transmittance and reflectance broadband optical monitoring. The use of a 400-1000 nm range combined with a signal-to-noise ratio of ~2500 in transmittance and 1000 in reflectance permits us to expect the manufacturing of high-performance non-quarter-wave designs. A first manufacturing of an 18-layer non-quarter-wave high-pass filter is provided. OCIS codes: 310.0310, 310.1860, 310.1620, 310.6860.

Various experiments and studies are conducted to study the role of order and disorder on the electronic performance of n-type ionic oxides, which are used as active or passive layers in thin film transistors (TFTs) processed at the room temperature. The analysis shows that the disorder does not affect the carrier mobility of the transistors much, as compared to that of semiconductors, though the electrical properties are found to be highly dependent on the oxygen vacancies.

Several electrical in situ and ex situ measurements are conducted to study the influence of various environmental conditions, like dry oxygen and moisture on the electronic transport and device stability of the polycrystalline pentacene transistors. The analysis reveals that such conditions inhibits the injection of holes in the highest occupied molecular orbital level of the film, which further leads to an apparent reduction of the charge carrier mobility, as well as the threshold voltage.

A combination of solvent cleaning and oxygen plasma cleaning processes is used to study and explain the effects of Si[O.sub.2] dielectric preparation on interfacial trap density in pentacene-based organic thin-film transistors. The reduction in the organic contamination at the semiconductor/dielectric interface following the plasma cleaning, leading to a reduction in the trapping states, is found to improve the threshold voltage of the devices.

The transmission ellipsometric function (TEF) of a film-substrate system relates the polarization change, upon transmission, of an electromagnetic wave obliquely incident on, and transmitted through, a filmsubstrate system. The behavior of the TEF depends on the category of the film-substrate system: negative, zero, or positive. The category is determined by the sign of [N.sub.1] - \[[square root of][N.sub.0][N.sub.2]: negative for a negative film-substrate system, zero for a zero system, and positive for a positive system. We discuss the behavior of the TEFs of the two transparent nonnegative film-substrate systems, zero and positive. We describe the TEF as two successive transformations and analyze its behavior as the angle of incidence and film thickness of the film-substrate system are changed. We use the constant-angle-of-incidence contours and constant-thickness contours to analyze and utilize that behavior. From the analysis and understanding of the behavior of the TEF, and from the definition of a polarization device as a film-substrate system that introduces prescribed polarization changes, we discuss the design of all possible types of polarization devices using either of the two systems. We present a design formula for each. We also present a general formula that is used for the design of any of the devices. Thin-film coatings are treated as polarization devices for the purposes of our discussion. We conclude with a brief discussion of suggested practical modifications to, and simplifications of, ellipsometric memory, which is an interesting application of polarization devices for which there is a patent pending. OCIS codes: 310.1620, 230.1150, 120.2130, 000.3870.

The long-term bias stress stability of poly(quaterthiophene) thin film transistors and slow stress process are described. The threshold voltage and the mobility, both are explicitly measured, a stress-induced mobility decrease is identified and it is seen that the slow stress also recovers but on a time scale of days, leading to a stabilized threshold voltage shift which does not change much for at least a few months.

The effect of interfacial water on the structural and electronic properties of pentacene monolayer deposited on Si[O.sub.2] is investigated. The combined structural and electronic results have suggested that the sensitivity to environmental conditions is not caused by a change in the amount of moisture at the interface, but it is predominantly related to condensed moisture at the free surface or at exposed grain boundaries in the film.

Low-frequency noise is studied in n-channel furnace solid phase crystallized and in laser solid phase crystallized (LSPC) polysilicon TFTs biased from weak to strong inversion. The results are attributed to the effects of the laser annealing on the active layer crystal quality.

The variation of giant magnetoresistance (GMR) behavior after thermal annealing at [T.sub.a]=250 degree Celsius as a function of the top free layer thickness of a GMR spin valve with nano-oxide layers (NOLs) is investigated, which is base upon a bulk scattering model. The two physical parameters are found to change consistently with the effects of thermal annealing on NOL.

The stability of fully deuterated amorphous silicon thin-film transistors is compared with their hydrogenated equivalent in terms of gate bias stress. Results reveal no detectable difference between hydrogenated and deuterated transistors in terms of stability under the application of a gate bias.

A method is described for the design of a thin-film all-dielectric polarizing beam splitter in which the transmittances for p- and s- polarized light are greater than 0.96 and less than 0.03, respectively, throughout the spectral region extending from 0.40 to 0.70 [[micro]meter], and for an angular field of 12 [degrees] measured in air.

An analytical saturation region model including an effective temperature and a quasi two-dimensional process is developed for amorphous silicon thin film transistors. The model precisely predicts the drain current properties that are consistent with experimental results. The drain source voltage plotted against output conductance indicates large output conductance values for thin oxide films in the transistors.

Transverse mode of a dielectric film waveguide having periodic corrugations on the film-substrate interfaces and film-cover are described by the second-order Bragg interaction, derived from the four coupled-mode equations. Characteristics such as output coupler, input coupler and frequency-selective filter and distributed feedback layer features are also determined. Frequency selective radiation is obtained by the correct choice of the design-parameters implemented in the substrate.

A thin-film reflecting interference filter has been designed and constructed for the purpose of suppressing grating harmonics when monochromatizing synchrotron radiation. It consists of a layer of Si evaporated onto a substrate and makes use of interference between wave fronts reflected from the layer-substrate and vacuum-layer interfaces to suppress higher harmonics. The filter has proved useful over the fundamental wavelength range of 400-1200 Angstrom (approximately 30-10 eV), maintaining a rejection ratio of fundamental to second harmonic exceeding 60. Calculations and measurements are presented, and the reflecting interference filter is compared with a critical-angle mirror used for the same purpose.

The low-temperature magnetization with epitaxial hexagonal HoMn[O.sub.3] films and single crystal is examined and compared. It is shown that a ferroelectric switching at room temperature is shown despite the leakage with a film resistivity of about [10.sup.9] [omega] cm.

Two media, A and B, are discussed in order to illustrate the media requirements and properties for the 230 Gb/in2 demonstration. Two media with similar areal moment, coercivity, intrinsic switching field, and barrier ratio resulted in significantly different recording properties.

We report on our systematic and detailed study of fabrication and characterization of polycarbonate thin-film optical waveguides. Various waveguide properties, such as refractive index, optical loss, waveguide thickness, dispersion as a function of temperature of waveguides and substrates, and the effect of thickness gradient on optical guiding losses, have been reported. A comparative study of the properties of waveguides fabricated with dioxane and tetrahydrofuran as solvents is also presented.

The various thermal treatment effects exhibited on the N-alkyl perylene diimide thin-film transistors (TFTs) with different alkyl chain are discussed. These effects are shown to be highly dependent on the substituted alkyl chain length.

The development of a high transmittance continuum domain twisted-vertical alignment (CDTVA) liquid crystal display (LCD) without domain walls defect and complex fabrication process is presented. The results have shown that the maximum transmittance of the CDTVA cell is similar to that of the twisted nematic mode thin-film transistor LCD.

The low-frequency noise properties in the inverted-staggered amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) with the silicon dioxide (Si[O.sub.2]) gate dielectric are examined. The results have shown that the 1/f noise in a-IGZO TFT samples is sensitive to the active layer quality and the low noise in a-IGZO TFT is associated with the s-orbital conduction in amorphous oxide semiconductor.

The various photoresponsive current-voltage characteristics of the organic thin film transistors (OTFTs) are analyzed. An increase in the incident light power is shown to lead to a significant reduction in the photosensitivity of the devices.

A quasidistributed fiber sensor is described for simultaneous measurement of liquid concentration and temperature based on Fresnel reflection. The results have shown that the sensing system has discriminated the concentration and temperature of a NaCl-[H.sub.2]O liquid with high concentration and temperature accuracies.

A theory of electronic transport in noncrystalline junctions is developed and junction transport is represented as hopping in both real space and energy space. The studies have correlated the current-voltage characteristics of noncrystalline, thin-film devices with material parameters and have predicted large ideality factors that increase under light and depend on applied bias.

A method for the rapid exchange of buffer solution during single-molecule observation via use a simple, transparent, all-plastic one-way valve integrated on a coverslip on a flow cell is described. The performance of the valve formed by using a membrane made of parylene covering a microhole is explained based on the observations from response of a rotary biomotor, [F.sub.1]-ATPase, for several buffer solutions in the fabricated chamber.

A threshold-voltage-corrected gate voltage is used to analyze the modification on the current-voltage characteristics of the n-channel organic thin film transistors fabricated on polyethylene naphthalate substrates. The improved performance of the device obtained with some of the self-assembled monolayer (SAM) treatments is attributed to both a better morphology of the semiconductor film, resulting in increased channel mobility, and to easier electron injection.

One of the method for tuning is to alter the material properties of the metals making up the resonant metamaterial to purposefully introduce resonance frequency and bandwidth damping. The classical microwave equation for thin-film resistors is used for developing a practical equivalent-circuit model for predicting the sensitivity of infrared metamaterials to complex film impedance.

The effect of the mechanical nozzle tolerance on droplet velocity and volume is examined by using mathematical models. These models are useful in isolating the effect of the mechanical nozzle tolerance on droplet velocity and volume from several other uncertainties and it is shown that a piezo-DOD inkjet printhead with a nominal nozzle diameter.

A new type of thin-film polarizing beam splitter (PBS) is proposed that is based on the effects of light interference and frustrated total internal reflection. This PBS has a significantly better performance than conventional thin-film PBS's. It is nonabsorbing, broadband, and wide angle and has high extinction ratios in both the transmitted and the reflected beams. The principles and theory of this PBS are described in detail. Several PBS's designed for the visible and the infrared spectral regions are described. The measured results for a prototype visible PBS of this type are presented as well. [C] 2000 Optical Society of America OCIS codes: 310.0310, 310.1620, 260.6970, 260.3160.