Abstract: Compact electrical connections (4) are formed on side-walls (1) of an infrared detector element having a step structure (1 to 3) over which a conductive layer (40) is deposited. Using a directional etching treatment, such as ion milling, the conductive layer (40) is removed from at least the bottom (3) of the step structure but is left lining the side-wall (1) as the connection (4). This permits formation of connections (4 and 44) in compact dense arrays, including plural-wavelength arrays in stacked bodies (10 and 20) on a circuit substrate (30).

Abstract: A thermal imaging device is manufactured by providing electrodes on opposite sides of a slab of ferroelectric or pyroelectric material. A sheet of electrically and thermally insulating material is bonded to the signal electrode layer on one side of the slab. An electrically conductive layer is provided on the insulating sheet. An array of spaced bores is then formed. Each bore extends through the electrically conductive layer down to the signal layer. The bores are then coated with electrically conductive material to electrically connect the signal electrode layer to the electrically conductive layer. Thereafter, a pattern of channels is formed surrounding the bores. The channels extend through the electrically conductive layer down to the slab, so as to form separate pillars of insulating material from the insulating sheet, and separate signal electrodes from the signal layer. Finally, the electrically conductive coated bores are connected to a circuit substrate by way of solder bumps.

Abstract: A thermal imaging device comprising a ferroelectric or pyroelectric slab bearing an infrared-permeable common electrode on one main surface and a signal electrode structure on the opposite main surface. The signal electrode structure is electrically connected to electrodes of a circuit substrate by means of solder bumps fused to conductors surrounded by a thermal insulating material. A problem in such thermally imaging devices is the heat conducted transverse to the longitudinal axes of the conductors, so that cross talk occurs between adjacent sensing regions. The transverse heat conduction between adjacent conductors is reduced by using conductors which are each in the form of a metal coating on a bore in a respective pillar of thermally insulating material, the pillars are separated by channels.

Abstract: The manufacture of an infra-red radiation detector element (51). A body of infra-red sensitive material (e.g. cadmium mercury telluride) secured to a substrate (22) is subjected to ion-etching to remove part of the material over the whole thickness of the element (51) at areas (56) between the contact areas of the element electrodes (35 and 36b) so as to define a current path between these electrodes (35 and 36b) which extends through the remaining material and is longer than the distance along a straight line between the electrodes (35 and 36b). This longer current path increases the charge-carrier transit time and resistance between the electrodes (35 and 36b) so that the responsivity of the detector element (51) can be improved while still producing a compact element structure because of the advantages of defining the current path by ion-etching.

Abstract: In the manufacture of an infra-red detector device, at least a portion of a surface of a body of mercury cadmium telluride is subjected to a conversion treatment to produce a surface layer, after which a heating step is performed. The present invention involves a simple and reproducible process for forming in the body a p-n junction of sufficiently good quality for such a detector which can be of a planar form so as to facilitate the formation of the detector element arrays in the body and the provision of contacts to the detector elements.

Abstract: A method of manufacturing an infra-red detector in which a printed form of lead-out contact pattern is applied to the surface of each infra-red sensitive element. A detector element of infra-red sensitive material is provided having at one major side at least one active surface area defined between spaced contact layers which extend over oppositely located curved edges of the element at said side. The element is adhered via the opposite major side to an insulating substrate having a contact pattern provided thereon. Electrically conductive material is deposited to forming interconnections between the contact layers on the element and adjacently situated end portions of lead-out conductors of the contact pattern.

Abstract: A method of forming in a wafer of infra-red sensitive material a large plurality of infra-red detector elements each comprising a body having a rectangular surface configuration with a pair of low resistance contacts extending on oppositely located curved edges of the body at opposite sides of a sensitive area of the body. A wafer of the infra-red sensitive material is adhered to a supporting body and by a combination of masking, etching and polishing techniques a plurality of elemental body portions of reduced thickness are defined in the wafer having oppositely located curved edges. Thereafter, electrically conductive material is deposited to form the contacts on the surface of each elemental body portion, and finally the elemental body portions and applied contacts are removed from the supporting body.