Self-assembled monolayer (SAMS) are commonly produced by immersing substrates in organic solutions containing trichlorosikme coupling agents. Unfortunately, such deposition solutions can also form alternate structures including inverse micelles and lamellar phases. The formation of alternate phases is one reason for the sensitivity of SAM depositions to factors such as the water content of the deposition solvent. If such phases are present, the performance of thin films used for applications such as minimization of friction and stiction in rnicromachines can be seriously compromised.Jnverse micelle formation has been studied in detail for depositions involving lH-, lH-,

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The erosion rate of resist during electron cyclotron resonance (ECR) plasma etching of II-VI semiconductors is the limiting factor for the selectivity (values range from 5:1 to 10:1). We have measured the erosion rates of AZ 1529, a commercially available diazonaphthoquinone (DNQ) novolak photoresist, under plasma conditions optimized for etching of the underlying semiconductor and have developed an in-situ technique to "harden" the resist by exposing it to an argon-only ECR plasma. A subsequent standard plasma process can then be used to etch the II-VI material, thereby achieving selectivity values greater than 50:1.

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Multicolor infrared focal-plane arrays (IRFPAs) offer important advantages over their single-color counterparts, primarily through spectral discrimination of a scene. The use of two or more wavebands significantly expands the capability of image processing algorithms to suppress spurious data and to enhance imagery of interest. Such detectors can be specifically tailored for identification of chemical species, thereby providing a chemical image of a scene. Multiple IR bands can provide accurate temperature measurements of gray bodies without knowledge of their emissivities.In this work, we describe the development of twocolor, HgCdTe-based, 128 ϫ 128, FPAs with spectral response tuned to the mid-wavelength infrared (MWIR) with cutoff wavelength CUTOFF ϳ4.5 m and short-wavelength infrared (SWIR) with cutoff wavelength CUTOFF~2 .5 m. This detector is the first of its kind, capable of providing simultaneous thermal (MWIR) and reflected (SWIR) imagery. The fabrication of this array was the result of a collaborative effort between the U.S. Army's Night Vision and Electronic Sensors Directorate (NVESD, Ft. Belvoir, VA) and Rockwell Scientific Company (RSC, Thousand Oaks, CA). Multilayer HgCdTe structures were deposited by molecular beam epitaxy (MBE) at NVESD.We report the development and fabrication of two-color mid-wavelength infrared (MWIR) and short-wavelength infrared (SWIR) HgCdTe-based focalplane arrays (FPAs). The HgCdTe multilayers were deposited on bulk CdZnTe (ZnTe mole fraction ϳ3%) using molecular beam epitaxy (MBE). Accurate control of layer composition and growth rate was achieved using in-situ spectroscopic ellipsometry (SE). Epilayers were evaluated using a variety of techniques to determine suitability for subsequent device processing. These techniques included Fourier transform infrared (FTIR) spectroscopy, Hall measurement, secondary ion mass spectroscopy (SIMS), defect-decoration etching, and Nomarski microscopy. The FTIR transmission measurements confirmed SE's capability to provide excellent compositional control with run-torun x-value variations of ϳ0.002. Nomarski micrographs of the as-grown surfaces featured cross-hatch patterns resulting from the substrate/epilayer lattice mismatch as well as various surface defects (voids and "microvoids"), whose densities ranged from 800-8,000 cm Ϫ2 . A major source of these surface defects was substrate particulate contamination. Epilayers grown following efforts to reduce these particulates exhibited significantly lower densities of surface defects from 800-1,700 cm Ϫ2 . Dislocation densities, as revealed by a standard defect-decoration etch, were 2-20 ϫ 10 5 cm Ϫ2 , depending on substrate temperature during epitaxy. The FPAs (128 ϫ 128) were fabricated from these epilayers. Preliminary performance results will be presented.

Deficits in early auditory information processing contribute to cognitive and psychosocial disability; this has prompted development of interventions that target low-level auditory processing, which may alleviate these disabilities. The frequency following response (FFR) is a constellation of event-related potential and frequency characteristics that reflect the processing of simple acoustic stimuli at the level of the brainstem and ascending portions of the auditory pathway. While FFR is a promising candidate biomarker of response to auditory-based cognitive training interventions, the psychometric properties of FFR in schizophrenia patients have not been studied. Here we assessed the internal consistency characteristics and magnitude of group differences across 18 different FFR parameters to determine which, if any, of these parameters demonstrate adequate internal consistency for use in intervention studies. Electroencephalography from 40 schizophrenia patients and 40 nonpsychiatric comparison subjects was recorded during rapid presentation of an auditory speech stimulus (6,000 trials). Patients showed normal response amplitudes but longer latencies for most FFR peaks and lower signal-to-noise ratios (SNRs) than healthy subjects. Analysis of amplitude and latency estimates of peaks, however, indicated a need for a substantial increase in task length to obtain internal consistency estimates above .80. In contrast, excellent internal consistency (> .95) was shown for FFR sustained responses. Only SNR scores reflecting the FFR sustained response yielded significant group differences and excellent internal consistency, suggesting that this measure is a viable candidate for use in clinical treatment studies. The present study highlights the use of internal consistency estimates of FFR to guide future intervention studies interested in individual differences among patients.

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