59 results about "Germanium crystal" patented technology

Devices for improving the capturing and utilization of high-energy electromagnetic radiation, for example, x-rays, gamma rays, and neutrons, for use in physical, medical, and industrial analysis and control applications are disclosed. The devices include optics having a plurality of optical crystals, for example, doubly-curved silicon or germanium crystals, arranged to optimize the capture and redirection of divergent radiation via Bragg diffraction. In one aspect, a plurality of optic crystals having varying atomic diffraction plane orientations are used to capture and focus divergent x-rays upon a target. In another aspect, a two- or three-dimensional matrix of crystals is positioned relative to an x-ray source to capture and focus divergent x-rays in three dimensions.

The invention generally relates to a crystal casting method using seed crystals, such as a directional solidification casting method. The crystal casting method includes a temperature gradient solidification method for manufacturing larger crystal materials in preset crystal orientation, wherein the crystal materials include polycrystalline materials and monocrystalline materials, and particularly include silicon or silicon germanium materials applicable to semiconductor and photovoltaic application. An existing crystal casting method using seed crystals has the problems of high energy consumption, more control difficulty, more impurity particles, easiness in generating mixed crystals, difficulty in obtaining large-sized monocrystalline materials and the like. The crystal casting method solves the problems by the aid of a bottomless crucible or a crucible with a notch at the bottom, a heat insulation area and a heat insulation position, fine crystal growth effect is achieved, the obtained casting monocrystalline or polycrystalline materials such as silicon or silicon germanium crystals have fewer defects or impurities, fine quality and excellent performance, and are applicable to the semiconductor and photovoltaic field.

The invention discloses a method and a device for growing a germanium crystal. The method comprises the following steps of: loading a first Ge raw material into a crucible which is provided with a crystal seed mixer with crystal seeds placed therein; loading a second Ge raw material into a loading container which is to be arranged in a quartz ampoule and is used for replenishing the Ge material; sealing the crucible and the loading container in the quartz ampoule; putting the quartz ampoule sealed with the crucible and the loading container into a crystal growing melting furnace provided with a movable ampoule supporting seat which supports the quartz ampoule; melting the first Ge raw material in the crucible to generate a molten mass; melting the second Ge raw material in the container and adding the second Ge raw material into the molten mass; controlling the crystallization temperature gradient of the molten mass so that the molten mass is crystallized when contacting the crystal seeds to form a monocrystalline germanium crystal bar; and cooling the monocrystalline germanium crystal bar. The invention also provides the device which can be used for implementing the method and comprises the loading container, wherein a process for forming the monocrystalline germanium crystal bar includes bluidling 0.3-2.5DEG / cm of temperature gradient in a crystal bar growing zone.

A portable radiation detector using a high-purity germanium crystal as the sensing device. The crystal is fabricated such that it exhibits a length to width ratio greater than 1:1 and is oriented within the detector to receive radiation along the width of said crystal. The crystal is located within a container pressurized with ultra-pure nitrogen, and the container is located within a cryostat under vacuum.

Method for limiting amount of radiation impinging on a radiation-sensitive detector device by directing radiation toward the detector, permitting the radiation to impinge upon the detector device when the radiation is below a predetermined threshold, and utilizing radiation having wavelengths different from signals of interest to initiate limiting of the radiation impinging upon the detector when the predetermined threshold is exceeded. The optical limiter includes an IR limiting layer pair selected so that energy from visible and near infrared radiation activates the optical limiter. The limiting layer pair may includes a layer closer to the source of radiation of e.g. vanadium dioxide, vanadium sesquioxide, or germanium crystal and a layer further from the source of radiation of e.g. chalcogenide glass, germanium crystal, or sodium chloride crystal.

Method for limiting amount of radiation impinging on a radiation-sensitive detector device by directing radiation toward the detector, permitting the radiation to impinge upon the detector device when the radiation is below a predetermined threshold, and utilizing radiation having wavelengths different from signals of interest to initiate limiting of the radiation impinging upon the detector when the predetermined threshold is exceeded. The optical limiter includes an IR limiting layer pair selected so that energy from visible and near infrared radiation activates the optical limiter. The limiting layer pair may includes a layer closer to the source of radiation of e.g. vanadium dioxide, vanadium sesquioxide, or germanium crystal and a layer further from the source of radiation of e.g. chalcogenide glass, germanium crystal, or sodium chloride crystal.

A measurement control system for diameter of Czochralski grown monocrystalline germanium is characterized by comprising a camera, an image processor and an automatic control unit, the camera acquires images of equal-diameter growth of monocrystalline germanium, an image processor recognizes the position of an aperture of a solid-liquid interface and calculates curvature radius of the aperture of the solid-liquid interface to allow for equal-diameter growth of monocrystalline germanium by the automatic control unit. The measurement control system for diameter of Czochralski grown monocrystalline germanium has the advantages that an image processing card only analyzes an aperture part of acquired images, data transmission quantity is reduced, and the requirement of the system for hardware performance is reduced. Complex mapping from ellipse to circle is not required, and equal-diameter control can be achieved according to a change rule of the curvature radius only by acquiring the curvature radius of a specified point. The camera can integrally transmit the acquired growth images of monocrystalline germanium for image processing and analyzing, and accordingly multiple devices are convenient to monitor in real time by a production operator and labor strength of growth of monocrystalline germanium is lowered. The existing devices can be utilized to the maximum limit, and repeated design and investment of an electrical control system are avoided.