US Government As Represented by the Secretary of the Army

USA As Represented by Secretary of the Navy

John H Pollard

William A Gutierrez

John B Ramsey, Jr

An apparatus and method for determining the relative proportions of two eents of a ternary compound from light reflected off a sample of the compound. The light is varied in wavelength and a graph of reflectance vs wavelength is stored. For a given compound of general form A.sub.x B.sub.1-x C, x may be determined by converting the stored graph to a graph of reflectance vs photon energy of the light, determining the photon energy of the light for the longest wavelength peak on the converted graph, and computing x from the equation E.sub.1 =a+bx+cx.sup.2 wherein a, b, and c are predetermined constants, and E.sub.1 is the photon energy in electron volts of the peak of interest.

Material analysis using reflected light

An array of semiconductive photoconductor detectors is formed on a substr with which the array forms a heterojunction. The array has a whole or partial overlayer of the same material as the substrate. Ohmic connections are made on the detectors and conductive read-out leads are connected to these connections; the leads are made of a conductor that forms a Schottky barrier with the substrate and overlayer. Ohmic connections are made to the substrate and overlayer such that a voltage bias may be applied between the substrate-overlayer combination and the array. The bais is used to control the accumulation layer in the substrate beneath the array in order to maximize sesitivity.

Methods of making infrared photoconductors with passivation control

A mercury-cadmium-telluride (HgCdTe) epitaxial detector array is formed on a cadmium telluride (CdTe) substrate. Connecting leads to the detectors are a molybdenum layer covered by a gold-germanium layer. These leads have excellent matches for the thermal coefficients of expansion of the HgCdTe and CdTe and provide ohmic contacts such that the D* of the array is greater than that of arrays made by prior processes using known lead materials, and the noise level is reduced by a factor of approximately three.

Infrared detector and method of making same

An infrared (IR) detector device comprised of a solid state, radiation ha and high resolution monolithic IR focal plane array for imaging applications. The monolithic IR focal plane array has a heterostructure injection scheme that prevents charged-coupled device (CCD) 'well filling' by using a heterojunction barrier between the absorber, or detector layer, and the transfer layer. Injection of signal charge into a CCD multiplexer is controlled by establishing a punch through condition between the absorber layer and the CCD channel. The detector layer and the CCD multiplexer are on different planes of the focal plane array.

Method of preparing a monolithic intrinsic infrared focal plane charge

An infrared (IR) detector device comprised of a solid state, radiation ha and high resolution monolithic IR focal plane array for imaging applications. The monolithic IR focal plane array has a heterostructure injection scheme that prevents charge coupled device (CCD) 'well filling' by using a heterojunction barrier between the absorber, or detector layer, and the transfer layer. Injection of signal charge into a CCD multiplexer is controlled by establishing a punch through condition between the absorber layer and the CCD channel. The detector layer and the CCD multiplexer are on different planes of the focal plane array.

Growing community of inventors

Alexandria, VA, United States of America

John H Pollard