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MOSFET detector evaluation

Description: From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). Metal-oxide-semiconductor devices have been evaluated as lowenergy (250 eV to 50 keV) x-ray dosimeters. They can be used to measure dosages as low as 1 rad (SiO/sub 2/) to as high as 10/sup 5/ rad (SiO/sub 2/). Their small size and basic simplicity make it possible to form arrays of dosimeters for x-ray imaging. When compared to thermoluminescent dosimeters (TLD's), photographic film, and thermopiles, MOSFET dosimeters offer distinct advantages in terms of their small size, their sensitivity to photon energies below 10 keV, and their adaptability to an electrical readout system. (auth)
Date: October 30, 1973
Creator: Ciarlo, D.R.
Partner: UNT Libraries Government Documents Department

High- and low-temperature bonding techniques for microstructures

Description: The ability to bond together two or more silicon wafers greatly expands the variety and complexity of silicon microstructures that can be designed and fabricated. At LLNL, microstructures have been used for many years as hardware in scientific experiments. The activity has recently been expanded into other areas to include microinstruments for biomedical applications and for chemical analysis. Both high temperature (1100{degrees}C) bonding techniques have been used, depending on the application. This paper discusses these applications with emphasis on the most extensive which is the fabrication of microchannel coolers for diode arrays.
Date: June 22, 1993
Creator: Ciarlo, D. R.
Partner: UNT Libraries Government Documents Department

Micromachined Fabry-Perot interferometric pressure sensor for automotive combustion engine

Description: In this paper, the authors report a dynamic cylinder pressure sensor for automotive combustion engine. The pressure is sensed by measuring the pressure-induced deflection of a membrane via a Fabry-Perot optical interferometric effect. The sensor is micromachined on a silicon wafer to minimize the cost and the size and to enhance the device quality in high-volume production mode. As a preliminary test, they measured the pressure of an air compressor using the micromachined miniature sensor.
Date: September 1, 1994
Creator: Lee, S.B.; Yu, C.M.; Ciarlo, D.R. & Sheem, S.K.
Partner: UNT Libraries Government Documents Department

A practical microgripper by fine alignment, eutectic bonding and SMA actuation

Description: A silicon microgripper with a large gripping force, a relatively rigid structural body, and flexibility in functional design is presented. The actuation is generated by Ni-Ti-Cu shape memory alloy (SMA) films and the stress induced can deflect each side of the microgripper up to 55 {mu}m for a total gripping motion of 110 {mu}m. When fully open, the force exerted by the film corresponds to a 40 mN gripping force on the tip of the gripper.
Date: April 21, 1995
Creator: Lee, A. P.; Ciarlo, D. R. & Krulevitch, P. A.
Partner: UNT Libraries Government Documents Department

High-temperature, radiation-tolerant electronics for the MMW (Multi-megawatt) Space Reactor Program

Description: One of the objectives of the Multi-Megawatt (MMW) space reactor program is to determine, within the next five years, what types of power electronic devices would be suitable for MMW space power applications. Suitable devices must be able to withstand high temperatures and high radiation fields. After investigating the literature on solid state device and miniature vacuum tube technologies, we have concluded that the miniature vacuum tube technology is, currently, the most promising. The main reason for choosing this technology, is because miniature vacuum tubes can operate at very high temperatures (775 K or potentially higher) and are tolerant to very high neutron fluence and gamma dose. Although there are still problems to be solved before miniature vacuum tubes can be used, the time required for their development will be much shorter than the five year period required by the MMW space reactor program. 13 refs., 3 figs., 3 tabs.
Date: October 17, 1986
Creator: Yee, J.H.; Orvis, W.J.; McConaghy, C. & Ciarlo, D.R.
Partner: UNT Libraries Government Documents Department

Electrochemical sensor/detector system and method

Description: An electrochemical detection system is described comprising in combination: (a) a multielement, microelectrode array detector containing means for acquiring a plurality of signals; (b) electronic means for receiving said signals and converting said signals into a readout or display providing information with respect to the nature and concentration of elements present in a solution being tested. Also described is the means of making the above described microelectrode detector.
Date: December 31, 1992
Creator: Glass, R. S.; Perone, S. P.; Ciarlo, D. R. & Kimmons, J. F.
Partner: UNT Libraries Government Documents Department

Fabrication and testing of a silicon immersion grating for infrared spectroscopy

Description: Recent advances in silicon micromachining techniques (e.g. anisotropic etching) allow the fabrication of very coarse infrared echelle gratings. When used in immersion mode, the dispersion is increased proportionally to the refractive index. This permits a very significant reduction in the overall size of a spectrometer while maintaining the same resolution. We have fabricated a right triangular prism (30{times}60{times}67 mm with a rectangular entrance face 30{times}38 mm) from silicon with a grating etched into the face of the hypotenuse. The grating covers an area of 32 mm by 64 mm and has a 97.5 PM periodicity with a blaze angle of 63.4{sup o}. The groove surfaces are very smooth with a roughness of a few manometers. Random defects in the silicon are the dominant source of grating scatter ({approx} 12% at 3.39 {mu}m). We measure a grating ghost intensity of 1.2%. The diffraction peak is quite narrow, slightly larger than the Airy disc diameter at F/12. However due to wavefront aberrations, perhaps 15--20% of the diffracted power is in the peak with the rest distributed in a diameter roughly five times the Airy disc.
Date: July 25, 1994
Creator: Kuzmenko, P. J.; Ciarlo, D. R. & Stevens, C. G.
Partner: UNT Libraries Government Documents Department