US Government As Represented by the Secretary of the Army

Gerard J King

Joseph F Martino, Jr

Aubrey J Dunn

A semiconductor substrate is bombarded by ions of sufficient energy to perate the surface of the substrate to some average predetermined depth. The substrate is then scanned by a laser beam having a small diameter compared to the substrate thickness and having sufficient energy to heat the substrate to the predetermined depth. The heat allows surface damage on the substrate from the ion bombardment to heal, and allows the ions and substrate to form a compound to the predetermined depth with controllable redistribution. This compound is the photodetector of the method. The ions may be implanted through a mask to produce isolated detector regions, or the entire substrate surface may be bombarded, and those regions not desired for detector regions may be removed by a laser beam of sufficient energy to cause evaporation of a layer of the substrate. Exemplary substrate and ions are respectively cadmium telluride and mercury.

Method of making photodetectors using ion implantation and laser

A layer of epitaxial silicon is grown on a silicon growth substrate, a thin layer of silicon dioxide or other suitable insulator is grown (in the case of silicon dioxide) or deposited (for other insulators) on the epitaxial layer, and a thick layer of polysilicon is grown on the dioxide layer. The silicon growth substrate is then removed, and the epitaxial layer is etched to form islands on the insulator layer. Some of the islands are doped to form an array of infrared sensitive detectors, and a large island is doped to act as CCD region. Electrical leads are fabricated, some to provide drive and output lines for the CCDs, other to provide connections of the detectors to respective CCDs, and yet others to provide common leads for the detectors.

Method of making silicon-insulator-polysilicon infrared image device

A silicon-on-sapphire, or silicon-on-spinel (SOS), epitaxial detector and readout structure and method of preparation. The present structure comprises silicon devices formed on sapphire, or spinel, substrates in which delineated silicon detectors, and electrically and optically isolated charge-coupled devices (CCDs), are used for signal readout from the detectors. The structure may be placed at the focal plane of an imaging infrared (IR) system for signal readout therefrom.

Method of preparation of SOS extrinsic infrared detector and read-out

SOS extrinsic infrared detector and read-out device

A layer of epitaxial silicon is grown on an epi-silicon growth substrate, a thin silicon dioxide layer is grown on the epitaxial layer, and thick layer of polysilicon is grown on the dioxide layer. The epi-silicon layer is then removed, and the epitaxial layer is masked and doped to produce both a region capable of CCD action and an infrared sensitive region. The doped epitaxial layer is orientially etched through a mask to produce isolated infrared sensitive areas to serve as detectors and an isolated area capable of CCD action. Coupling regions are also doped on the CCD ares. The detectors and the CCD area are each in the shape of a frustum of a right rectangular pyramid, with its base on the silicon dioxide layer. Electrical pads are grown to form CCDs. Electrical leads are grown, some to connect respective CCDs to respective coupling regions, some to serve as drive lines for the CCDs, some as common lines for the detectors, and some as connecting lines between respective detectors and coupling regions. A perforated opaque mask is placed on the opposite side of the polysilicon from the silicon dioxide layer, with the perforations aligned with respective ends of the detectors.

Method of making silicon-insulator-polysilicon infrared imaging device

An infrared imaging device is made by SIP chip growth technology to form an array of extrinsic silicon infrared detectors on an insulating layer which is on one side of an infrared-transparent polysilicon layer. A perforated mask is on the opposite side of the polysilicon layer. The detectors each have the shape of a frustum of a right rectangular pyramid. During processing of the chip for detectors, charge coupled devices (CCDs) are also made on the chip. These CCD's are indirectly connected to respective detectors and to readout lines on the chip.

Silicon-polysilicon infrared image device with orientially etched

A layer of epitaxial silicon is grown on a silicon growth substrate, a thin ayer of silicon dioxide or other suitable insulator is grown (in the case of silicon dioxide) or deposited (for other insulators) on the epitaxial layer, and a thick layer of polysilicon is grown on the dioxide layer. The silicon growth substrate is then removed, and the epitaxial layer is etched to form islands on the insulator layer. Some of the islands are doped to form an array of infrared sensitive detectors, and a large island is doped to act as CCD region. Electrical leads are fabricated, some to provide drive and output lines for the CCDs, other to provide connections of the detectors to respective CCDs, and yet others to provide common leads for the detectors.

Silicon-insulator-polysilicon infrared imaging device and method of

A balanced metal-oxide-semiconductor detector is provided which senses only he difference in radiation level between elements of a radiation image. The same detector is provided in a silicon base structure modified to be responsive to band-gap energy at longer wavelengths than are normally associated with such structures.

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Alexandria, VA, United States of America

Gerard J King