Abstract

Provided is (1‐x‐y)Pb(In1/2Nb1/2)O3‐yPb(Mg1/3Nb2/3)O3‐xPbTiO3, which is doped with Mn and Fe and prepared using an improved Bridgman method, wherein 0.15≤1‐x‐y≤0.38, 0.36≤y≤0.57, and 0.26≤x≤0.30, the crystallographic direction is [111], and the Curie temperature thereof is improved greatly compared with that of a relaxation ferroelectric single crystal (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 which is doped with Mn.

IPC Classes  ?

• C30B 29/22 - Complex oxides
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates
• C30B 29/30 - NiobatesVanadatesTantalates
• C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

A process method for inhibiting the crack formation and cracking of a manganese doped pyroelectric monocrystalline, wherein the chemical composition of the manganese doped pyroelectric monocrystalline is Mn-(1-x-y)Pb(In 1/2Nb 1/2)O 3-yPb(Mg 1/3Nb 2/3)O 3-xPbTiO 3, wherein x＝0.35-0.42, y＝0.30-0.45, 1-x-y＝0.20-0.29, and the doping level of Mn is 0-5.0%. The preparation method for the material is an improved Bridgman method, comprising the processes of synthesizing a raw material, warming and melting, seeding with a crystal seed and crystal growing. The method overcomes the disadvantages of easy crack formation on a crystal and crystal cracking because of the Mn doping in the prior art, and provides an implementation method for preparing a large size pyroelectric monocrystalline with a high quality, and increasing the yield and performance reliability.

IPC Classes  ?

• C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
• C30B 29/22 - Complex oxides
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates

Abstract

Disclosed is a method for preparing a large-size high-homogeneity manganese-doped pyroelectric single crystal. The chemical composition of the manganese-doped pyroelectric single crystal is as follows: Mn-(1-x-y)Pb(In1/2Nb1/2)O3-yPb(Mg1/3Nb2/3)O3-xPbTiO3, wherein x＝0.35-0.42, y＝0.30-0.45, and 1-x-y＝0.20-0.29. The doping amount of Mn is 0-5%. The preparation method for the material is an improved Bridgman method, which comprises raw material synthesis, seed crystal selection, growth process control, defect regulation and control, etc. The present invention overcomes the disadvantages in the prior art that it is difficult to dope the Mn element, the crucible easily leaks, and a defect is easily generated in the [001] direction, and provides an implementation method for the industrial growth of large-size pyroelectric single crystals.

IPC Classes  ?

• C30B 29/22 - Complex oxides
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates
• C30B 29/30 - NiobatesVanadatesTantalates
• C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

Provided is an Mn doped (1-x-y)Pb(In1/2Nb1/2)O3-yPb(Mg1/3Nb2/3)O3-xPbTiO3 prepared by an improved Bridgman method, in which 0.20≤1-x-y≤0.29, 0.30≤y≤0.45, and 0.35≤x≤0.42, and the Curie temperature of which is greatly enhanced compared with that of an Mn doped relaxation ferroelectric single crystal (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3.

IPC Classes  ?

• C30B 29/22 - Complex oxides
• C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates

Abstract

Provided is a pyroelectric relaxor ferroelectric infrared detector. The detector comprises: a base provided with a pin; a casing having one or a plurality of windows, the casing being packaged together with the base to form an accommodating space; a sensitive element chip arranged within the accommodating space; electrodes respectively arranged on an upper surface and a lower surface of a pyroelectric relaxor ferroelectric single crystal sensitive element; an absorption layer covering the upper surface of the single crystal sensitive element; a frame supporting the single crystal sensitive element; an amplification circuit using a voltage mode or a current mode. An upper electrode arranged on the upper surface is a single electrode, and a lower electrode arranged on the lower surface comprises a left electrode and a right electrode separated from one another. The left electrode and the right electrode are not connected to one another to form the lower electrode as a divided electrode. Therefore, dielectric noise of device preparation is reduced, and the response rate and specific detectivity of the detector is increased.

IPC Classes  ?

• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

Provided is a sensitive element chip, comprising one or a plurality of pyroelectric relaxor ferroelectric single crystal sensitive elements. An upper and a lower surface of the pyroelectric relaxor ferroelectric single crystal sensitive element are respectively provided with electrodes. An upper electrode arranged on the upper surface is a single electrode, and a lower electrode arranged on the lower surface comprises a left electrode and a right electrode separated from one another. The left electrode and the right electrode are not connected to one another to form the lower electrode as a divided electrode. The present invention reduces dielectric loss and the capacitance of the sensitive element, the pyroelectric coefficient is higher, and the response rate and specific detectivity of a device prepared using the sensitive element chip are increased.

IPC Classes  ?

• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

A thinning method for a pyroelectric relaxor ferroelectric single crystal, comprising rough grinding being performed on a first surface of a single crystal and chemical mechanical polishing being performed on the rough-ground first surface, rough grinding being performed on a second surface of the single crystal and chemical mechanical polishing being performed on the rough-ground second surface, wet etching being performed on the ground single crystal, and high temperature annealing treatment being performed on the etched single crystal. A combination of grinding, etching and annealing is used, attaining effective thinning of pyroelectric relaxor ferroelectric single crystal material, and ensuring the performance of the material after thinning.

IPC Classes  ?

• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point
• C30B 29/30 - NiobatesVanadatesTantalates
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates

Abstract

Provided is a pyroelectric relaxor ferroelectric single crystal infrared detector. The detector comprises: a base provided with a pin; a casing having a window, the casing being packaged together with the base to form an accommodating space; a sensitive element (7) arranged within the accommodating space, the sensitive element being made from a relaxor ferroelectric single crystal; upper electrodes (5, 6) and a lower electrode (8) respectively arranged on an upper surface of the sensitive element and a lower surface of the sensitive element; an absorption layer (9) covering the upper electrodes of the sensitive element; a frame (3) supporting the sensitive element; an amplification circuit connected to the sensitive element. The present detector has advantages such as a high response rate, low noise and a high detection rate.

IPC Classes  ?

• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

A polarisation method for a sensitive element chip. The sensitive element chip comprises one or a plurality of pyroelectric relaxor ferroelectric single crystal sensitive elements. An upper and a lower surface of the pyroelectric relaxor ferroelectric single crystal sensitive element are respectively provided with electrodes. An upper electrode arranged on the upper surface is a single electrode, and a lower electrode arranged on the lower surface comprises a left electrode and a right electrode separated from one another. The left electrode and the right electrode are not connected to one another to form the lower electrode as a divided electrode. The left electrode is connected to a positive end of a power source, the right electrode is connected to a negative end of the power source, and the upper electrode is grounded. Via the present polarisation method, full use may be made of the advantages of distributed electrodes, dielectric loss and the dielectric constant may be reduced, and high temperature polarisation may be performed.

IPC Classes  ?

• H01L 37/02 - Thermoelectric devices without a junction of dissimilar materials; Thermomagnetic devices, e.g. using Nernst-Ettinghausen effect; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof using thermal change of dielectric constant, e.g. working above and below the Curie point

Abstract

A post-treatment method for a pyroelectric relaxor ferroelectric single crystal, sequentially comprising grinding and chemical mechanical polishing being successively carried out on a first surface of a single crystal, grinding and chemical mechanical polishing being successively carried out on a second surface opposite the first surface, wet etching being performed on the single crystal, and annealing treatment being carried out on the wet-etched single crystal. Defects and surface stress produced in grinding steps of the single crystal are removed, dielectric loss and dielectric noise of the single crystal are reduced, and the detection performance of a pyroelectric relaxor ferroelectric single crystal detector is improved.

IPC Classes  ?

• H01L 41/187 - Ceramic compositions
• H01L 21/324 - Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering
• H01L 21/477 - Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering
• C30B 29/32 - TitanatesGermanatesMolybdatesTungstates

Abstract

The present invention provides the methods to fabricate thallium doped cesium iodide (CsI:Tl) scintillators with high light yield and reduced afterglow,the scintillators prepared according to the disclosed method,and their applications in radiation detection.

IPC Classes  ?

• C30B 29/12 - Halides
• G01T 1/202 - Measuring radiation intensity with scintillation detectors the detector being a crystal

Abstract

An optically controlled silicon carbide (SiC) photoconductive switch is provided. The switch comprises a photoconductive wafer and electrodes. The photoconductive wafer is a silicon carbide wafer, and has following well-polished crystal planes: at least one (100) m plane, at least two (110) a planes, wherein the (100) m plane or the (110) a planes are planes towards light and optically connected to an initiated optical source, and the electrodes have good electricity performance with the (110) a planes or the (100) m plane. When the (100) m plane is used as the plane towards light, the electrodes electrically connect to the (110) a planes; and when the (110) a planes are used as the planes towards light, the electrodes electrically connect to the (100) m plane.

IPC Classes  ?

• H01L 31/101 - Devices sensitive to infrared, visible or ultraviolet radiation
• H01L 31/0224 - Electrodes
• H01L 31/036 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof characterised by their semiconductor bodies characterised by their crystalline structure or particular orientation of the crystalline planes

Abstract

An apparatus with two-chamber structure for growing silicon carbide (SiC) crystals is disclosed. The apparatus comprises a sample feed chamber and a crystal growth chamber, both of which are separately connected with each other by a vacuum baffle valve and connected with a vacuum system. The crystal growth apparatus ensures that the insulation materials in the crystal growth chamber cannot contact with air, minimizes the adsorption of nitrogen and pollutants on the insulation materials and the growth chamber, improves purity of SiC crystals and achieves precise control of the impurities so that growth of high-quality SiC crystals such as conductive, doped semi-insulating or high-purity semi-insulating SiC crystals and the like is enabled.

IPC Classes  ?

• C30B 23/00 - Single-crystal growth by condensing evaporated or sublimed materials
• C30B 29/36 - Carbides

Abstract

A high-purity tellurium dioxide (TeO2) single crystal and its manufacturing method are provided. The method comprises the following procedures: firstly performing a first single crystal growth, and then dissolving the resulting single crystal again, thereafter adding a precipitation agent to form powder, and finally performing a second single crystal growth of as-prepared powder to obtain the high purity single crystal. The TeO2 single crystal prepared according to present invention is of high purity, especially with a content of radioactive impurities such as U and Th decreased to a level of 10-13 g/g.

IPC Classes  ?

• C30B 29/46 - Sulfur-, selenium- or tellurium-containing compounds
• C30B 29/16 - Oxides
• C30B 15/00 - Single-crystal growth by pulling from a melt, e.g. Czochralski method