Abstract:
In electro-optical detectors which include as elements a photoemitting photocathode and anode, a photoemitting diode is fabricated which lowers the diode's work function, thus reducing the cooling requirement typically needed for this type of device. The work function is reduced by sandwiching between the photocathode and anode a liquid medium of the formula NR.sub.3 and having an electron affinity for the electrons of the photocathode, which liquid medium permits free electrons leaving the photocathode to remain as stable solvated species in the liquid medium. Thus, highly light-absorbent, and therefore thin, metallic layers can be used for detection, thereby reducing dark current at a given temperature, with a consequent reduction in cooling requirements at constant detector performance.
Abstract:
A detector for infrared radiation, having a multicell photosensor disposed at the top of a cold finger in an evacuated container, comprises a stack of annular ceramic layers coaxially surrounding the cold finger and serving as supports for several arrays of radially extending metallic strips screen-printed on respective layers in angularly offset relationship. The metallic strips are conductively connected to respective cells of the sensor to serve as output leads thereof. The conductive connections include axially extending metal pins spacedly surrounding the cold finger while being linked with the sensor cells by short, thin wires spanning an intervening annular gap.
Abstract:
An improved method for providing electrical connection to a photodetector in a Dewar flask is disclosed. A plurality of conductive paths are formed on the inner flask of the Dewar. Each of the conductive paths extends from the side surface on to the top surface of the inner flask. A photodetector having lead tabs is mounted to the top surface of the inner flask with the lead tabs aligned with the conductive paths. The lead tabs are bonded to the conductive paths to provide electrical connection to the photodetector.
Abstract:
A bolometer which operates at room temperature and which can be made sensitive to all blackbody radiation in the visible spectrum and extending into the infrared, depending upon the nature of a faceplate used. The bolometer is constructed by sandwiching a suitable semiconductor in smoke form between gold black as one electrode and a flooding electron beam as the other, the sensing layer being mounted in a vacuum tube.
Abstract:
Infrared detector material is formed by the epitaxial growth of a single crystal alloy of the two III-V compounds InAs and InSb on an InAs substrate. In the method of such growth, a liquid solution is prepared with excess indium solvent, InSb, and sufficient InAs to saturate the indium at 500* C. The InAs substrate, oriented in the III direction is immersed in the solution, and the substrate and the solution are brought to equilibrium at approximately 500* C. Slowly lowering the solution temperature causes a single crystal to be epitaxially grown on the substrate as a solid homogeneous InAs-InSb solution. Composition of the crystal is a function of solution composition and may be controlled by dissolving selected quantities of InSb in the solution.
Abstract:
INFRARED DETECTOR MATERIAL IS FORMED BY THE EPITAXIAL GROWTH OF A SINGLE CRYSTAL ALLOY OF THE TWO III-V COMPOUNDS INAS AND INSB ON AN INAS SUBSTRATE. IN THE METHOD OF SUCH GROWTH , A LIQUID SOLUTION IS PREPARED WITH EXCESS INDIUM SOLVENT, INSB, AND SUFFICIENT INAS TO SATURATE THE INDIUM AT 500*C. THE INAS SUBSTRATE, ORIENTED IN THE (III) DIRECTION IS IMMERSED IN THE SOLUTION, AND THE SUBSTRATE AND THE SOLUTION ARE BROUGHT TO EQUILBRIUM AT APPROXIMATELY 500*C. SLOWLY LOWERING THE SOLUTION TEMPERATURE CAUSES A SINGLE CRYSTAL TO BE EPITAXIALLY GROWN ON THE SUBSTRATE AS A SOLID HOMOGENEOUS INAS-INSB SOLUTION. COMPOSITION OF THE CRYSTAL IS A FUNCTION OF SOLUTION COMPOSITION AND MAY BE CONTROLLED BY DISSOLVING SELECTED QUANTITIES OF INSB IN THE SOLUTION.