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Topic: Specific detectivity

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	Research
		This enables high detectivity pyroelectric thermal detectors to be fabricated on micromachined thermal isolation structures integrated on CMOS read-out circuitry, since the amorphous semiconducting phase of YBaCuO, used in these imaging devices, is deposited at ambient temperature with no need of high temperature post-annealing.
		Fluctuations in the detected signal due to temperature fluctuations noise, Johnson noise and amplifier noise will be measured as a function of bias conditions, thermal conductance of the detector element to the substrate, and temperature to fully characterize the origin of these noise components.
		Detectivities in the order of 5 x 1010 cm Hz1/2/W are predicted which is far superior to other uncooled materials and comparable to cooled HgCdTe.
	engr.smu.edu /ee/solidstate/ir-research-summary.htm (2946 words)

	LEOT Laser Tutorial - Course 4: Laser Electronics - Module 8: Optical Detectors (Site not responding. Last check: 2007-10-15)
		Optical detectors include photon detectors, in which one photon of light energy releases one electron that is detected in the electronic circuitry, and thermal detectors, in which the optical energy is converted into heat, which then generates an electrical signal.
		Often the detection of optical energy must be performed in the presence of noise sources, which interfere with the detection process.
		The exact value of detectivity for a specific photoconductor depends on the operating temperature and on the field of view of the detector.
	repairfaq.ece.drexel.edu /sam/CORD/leot/course04_mod08/mod04-08.html (11228 words)

	Lancaster Mid-Infrared Optoelectronics Group - Detectors
		The most important figure of merit for a MIR photodetector is the specific detectivity D*.
		It is seen that the detectivity decreases with increase in the interface trap density at the heterointerface.
		Variation of the detectivity of the HJ detector with wavelength.
	www.lancs.ac.uk /depts/spc/research/condmatt/mid-ir/detect1-p.htm (807 words)

	Nat' Academies Press, Expanding the Vision of Sensor Materials (1995)
		The key figure of merit that is usually employed is the specific detectivity D, which describes the smallest detectable* signal (Accetta and Shumaker, 1993).
		The specific detectivity, D, is the detectivity* D for a 1-Hz bandwidth and a 1-cm
		The specific detectivity, D, is a normalized measure related to the inverse of the smallest signal that can be detected*.
	www.nap.edu /books/0309051754/html/122.html (1183 words)

	Sensors Magazine Online - SENSOR INDUSTRY DEVELOPMENTS AND TRENDS (Site not responding. Last check: 2007-10-15)
		The intensity loss of an IR light beam in a specific spectral region is a direct measure of the target gas.
		An infrared absorption gas detector includes an IR light source; a measurement volume where the gas to be detected is confined; an element (optical filter), which allows for selecting the desired wavelength region; and a detector for measuring radiation intensity.
		Medical applications where optical gas detection is well established include breath control (e.g., monitoring alcohol content in exhalation breath, monitoring CO2 content in the patient's exhaled breath, prenatal supervision of inhaled/exhaled gases, monitoring of anesthetic gases in operating areas).
	www.sensorsmag.com /resources/businessdigest/sbd1001.shtml (2265 words)

	[No title] (Site not responding. Last check: 2007-10-15)
		In addition, the quantum well detectors have considerably higher detectivity than simpler semiconductor structures, and one may be tempted to claim that all additional research and development effort should be applied to the high performance QWIP structures.
		As mentioned before, the detectivity of IR photodetectors is limited by the noise associated with dark current and thermal fluctuations.
		To use either structure for low NEP performance IR detection, it is necessary to cool the devices to liquid nitrogen temperatures to reduce the dark currents and thermal fluctuations.
	www.eas.asu.edu /~roedel/ece300s03/bmdosbir99.doc (3970 words)

	Specific detectivity - Wikipedia, the free encyclopedia (Site not responding. Last check: 2007-10-15)
		Specific detectivity: For a photodetector, a figure of merit used to characterize performance, equal to the reciprocal of noise equivalent power (NEP), normalized to unit area and unit bandwidth.
		Note: Specific detectivity, D *, is given by where A is the area of the photosensitive region of the detector and Δf is the effective noise bandwidth.
		This page was last modified 03:13, 19 February 2005.
	en.wikipedia.org /wiki/Specific_detectivity (82 words)

	Thesis
		The detector noise is based on the specific detectivity of the material type.
		The noise is computed as a Noise-Equivalent Radiance (NER) and is based on the detectivity.4 The inputs for this module include: the specific detectivity, passband, detector time constant, F#, transmission of the filter, and the transmission of the optics.
		The NEP is a function of the detector area, detector bandwidth, and the specific detectivity:
	www.cis.rit.edu /research/thesis/bs/1998/bleeze/thesis.html (3108 words)

	D.T.S. GmbH: Thin Film Thermoelectric Generators
		The Infrared Sensors IRS-235 M and IRS-235 F detect actively infrared radiation after the thermo-electric principle (235 thermopiles).
		The detectors are made by thinfilm technology and are characterized by a flat, space-saving and robust device construction, do not need a filter window, possess a high responsivity, are not influ-enced by heat conduction and heat convection of the surroundings and are resistant against high intensity of heat radiation.
		Their geometry and parameters are adjustable to specific applications.
	www.dts-generator.com /sen-txe.htm (142 words)

	Oral Reports
		For organization of processes in LIC as are used as well four step signal, four supplying voltage values two of which provide application of voltage bias to PSE and must have low pulsation values.
		Histograms and diagrams of spreading photodiode current in APD in the operating point, photosensitivity and specific detectivity D* of APD with a cutoff wavelength by the level of l
		Maximal detectivity of semiconductor photodetectors is arrived at the temperature range of 80 – 300
	www.vimi.ru /confer/orion/oral-1.htm (2979 words)

	[No title]
		Quantum dot detectors have already demonstrated normal incidence MWIR operation at temperatures as high as 150K and the reported results in the literature from several groups show significant promise for this technology.
		Nevertheless the responsivity and specific detectivity of QDIPs is significantly lower than those observed in mercury cadmium telluride (MCT) detectors.
		To the best of our knowledge, this is the highest responsivity and detectivity reported in a LWIR QDIP at 78K.These results and the mechanism for the large gain that is observed in these detectors will be discussed in detail in the presentation.
	www.chtm.unm.edu /AA_NEWS_STORIES_DATA/Special_Events/Napa_Workshop_6_02/Napa_abstracts/Abstract_Krishna.doc (223 words)

	Posters
		The technological process of film deposition included additional recording of main characteristics of deposited layer (the rate of the growth and the layer’s thickness, the dynamics of crystallites forming and etc) and should integrate with standard planar CMOS technologies.
		We have created the matrix multiplexer (its general specifications are shown in the table) to improve circuit and topological solutions.
		Therefore we preferred to choose SAs, since they allow, by merely changing the lay-out of plating layers, to create ICs, meeting the requirements, set by a TD of a specific PD. And it, moreover, is executing in short times and at a low cost.
	www.vimi.ru /confer/orion/posters-b-1.htm (3931 words)

	Doubt on 'Specific Detectivity' for photovoltaic IR detector
		Doubt on 'Specific Detectivity' for photovoltaic IR detector
		Its is said that D* is normalized with A and Δf, and D* is therefore independent of A and Δf, D* is the intrinsic property of the detector material.
		But I found in the specification of some photovoltaic IR detectors made of (Hg,Cd,Zn)Te semiconductor.
	www.edaboard.com /ftopic110052.html (306 words)

	Re: Satellite eavesdropping of 802.11b traffic
		If you assume a perfect vacuum (and note that the athmosphere is fairly opaque at 2.4 Ghz) and perfect antenna's etc - then the specific detectivity needed in space suggests a not unresonably sized (m2's) and cold antenna (below 180k) by very resonably NEP which is commercially available.
		Given the noise from the earth background (assuming a fl body radiator) at 2.4, the Sun and the likelyhood that that largish antenna catches a fair chunk of exactly that then you are at the edge of what would be realistic.
		There are some good papers on Lidar and Radar detections of clouds in the 3Ghz range at 12km which should give you more of an idea of the spatial resolution you could accomplish.
	www.mail-archive.com /cryptography@metzdowd.com/msg02153.html (403 words)

	Handbuch für Thermoelectrically cooled infrared photoconductive detectors
		and detectivity D* as measured in respect of fl body source, determination of specific responsivity R
		) is specific responsivity at load resistance closed to dark resistance value of the detector element.
		Not needed to be carried out is any regular service work during whole period of time of keeping if the detector is kept in parcel or container of manufacturer or assembled into customer´s apparatus.
	www.oec-gmbh.de /applikationen/appl-manual-en.shtml (797 words)

	Title page for etd-0717104-160053
		The specific detectivity (D*) measured at 200 Hz has the maximum value of 1.1×108 cmHz1/2/W with twelve annealed layers.
		Finally, the voltage responsivities (Rv) of LT thin film increases from 8398 V/W to 9537 V/W, and the specific detectivity (D*) increases from 1.1×108 cmHz1/2/W to 2.67×108 cmHz1/2/W after backside etching.
		The results show that the detectivity can be improved after backside etching.
	etd.lib.nsysu.edu.tw /ETD-db/ETD-search/view_etd?URN=etd-0717104-160053 (329 words)

	Journal of Electronic Materials: A CdTe Passivation Process for Long Wavelength Infrared HgCdTe Photo-Detectors
		An order of magnitude improvement in responsivity and a factor of 4 increase in specific detectivity (D*) is achieved by CdTe passivation over AO passivation.
		Responsivity and specific detectivity are measured at 77 K using a fl body source (Micron M360), a rectangular chopper (EG&G Princeton-192), a lock-in amplifier (Stanford SR 830) and a data acquisition and control unit (HP 2510).
		Fabrication of high-performance detectors critically depend on a suitable technology to produce low surface recombination velocity as the surface effects largely dominate the effective lifetime of excess carriers in thin HgCdTe detectors.
	www.findarticles.com /p/articles/mi_qa3776/is_200509/ai_n15350656 (1407 words)

	Active Skim View of: CHAPTER 5: LWIR SENSORS
		LWIR Detectors Based on Strained-Layer Superlattice Structures Desired band gaps for LWIR detection can be artificially created in semiconductor heterostructures by employing lattice strain to cause major changes in electronic and optical properties of the material.
		To date, however, because of 1/ƒ noise, the detectivities of SLS photovoltaic detectors operated at video frequencies are lower than those composed either of mercury-cadmium-telluride or of gallium-arsinide/AlGaAs quantum wells.
		At these longer wavelengths, the theoretical detectivity of InSb/InAsSb SLS infrared detectors exceeds that of MCT detectors that have the same long-wavelength limit.
	www.nap.edu /nap-cgi/skimit.cgi?isbn=0309051754&chap=62-72 (662 words)

	Infrared Detectors
		Very high values of specific detectivity D* are reached by modern ion beam etching technologies.
		If you can't find what you want then please contact us and we will try to help.
		Lithium Tantalate infrared detectors with high specific detectivity
	www.scitec.uk.com /infrared_detectors (89 words)

	Specific detectivity -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-10-15)
		Specific detectivity -- Facts, Info, and Encyclopedia article
		Note: Specific detectivity, D *, is given by where A is the area of the photosensitive region of the (Any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner) detector and Δf is the effective noise bandwidth.
		Source: from (Click link for more info and facts about Federal Standard 1037C) Federal Standard 1037C
	www.absoluteastronomy.com /encyclopedia/s/sp/specific_detectivity.htm (76 words)

	High-Performance Micromachined Linear Arrays of Thermopiles
		/rl, where a is the Seebeck coefficient, r is the electrical resistivity, and l is the thermal conductivity.] The signal-to noise ratio of an infrared detector can be described by the specific detectivity, (D*).
		The thin-film thermoelectric wires are electrically connected to each other and gold interconnect wiring with contact pads made of gold film deposited over titanium film.
		When exposed to radiation from a 1,000 K fl-body source, the detectors exhibited zero frequency responsivity values of 1,100 V/W and specific detectivites of D* = 1.4 ´ 10
	www.nasatech.com /Briefs/May01/NPO20402.html (520 words)

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