Method for preparing large size lithium tetraborate piezoelectric crystal

A lithium tetraborate and piezoelectric crystal technology is applied in the field of preparation of lithium tetraborate piezoelectric crystals, which can solve problems such as crystal cracking, seeding failure, crucible material leakage, etc., so as to reduce crystal cost, improve yield and growth efficiency, The effect of reducing the difficulty of growth

Inactive Publication Date: 2009-03-04
SHANGHAI INST OF TECH
View PDF0 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the traditional descent method often encounters problems such as crucible leakage, inoculation failure, and crystal cracking when growing four-inch lithium tetraborate crystals, and the yield is less than 20%. The bottleneck of large-scale application of lithium crystal

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing large size lithium tetraborate piezoelectric crystal

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0016] Press 5kg of slightly boron-rich lithium tetraborate polycrystalline material into a dense cylindrical block, and put it into a 60mm×110mm×300mm Pt crucible. A 60mm-long -oriented seed crystal is placed on the bottom of the crucible, and placed The material is placed in a high-temperature zone at an appropriate position in the descending furnace. The furnace temperature is controlled at 950-1000°C, and the crucible descending rate is 0.2mm / h. High-quality large single crystals with a thickness of 60mm, a width of 110mm, and a length of 160mm can be grown. After the growth, the crucible was returned to the constant temperature zone in the furnace, annealed at 800°C for 10 hours, cooled to room temperature, and the crystal was taken out. Accurately orientate along the large side of the crystal, mechanically dig out the cylindrical crystal perpendicular to the surface, and obtain a large-sized lithium tetraborate ingot with a diameter of 4 inches and a thickness of 60 mm. ...

Embodiment 2

[0018] Press 48kg of lithium tetraborate polycrystalline material into dense cylindrical material blocks, and put them into six Pt crucibles with a size of 80mm×120mm×300mm, and place a -oriented seed crystal with a length of 60mm on the bottom of the crucible, and place The raw material is placed in a high-temperature zone at an appropriate position in the descending furnace. The furnace temperature is controlled at 950-1000°C, and the crucible descending rate is 0.4mm / h. Six high-quality large single crystals with a thickness of 80mm, a width of 120mm, and a length of 180mm can be grown. After the growth, the crucible was returned to the constant temperature zone in the furnace, annealed at 800°C for 12 hours, cooled to room temperature, and the crystal was taken out. The crystal is accurately oriented toward the large surface, and the cylindrical crystal is mechanically removed perpendicular to the surface, and 6 large-size lithium tetraborate crystal rods with a diameter of...

Embodiment 3

[0020] Press 6kg of lithium tetraborate polycrystalline material into a dense cylindrical block, put it into a 50mm×160mm×300mm Pt crucible, and place a -oriented seed crystal with a cross-section of 30mm×40mm and a length of 60mm in advance on the bottom of the crucible. Put it in a proper position in the descending furnace so that the raw material is in the high temperature zone, the furnace temperature is controlled at 950-1000°C, and the crucible descending rate is 0.6mm / h. After the growth, the crucible returned to the constant temperature zone in the furnace, annealed at 700°C for 10 hours, slowly lowered the temperature and took out the crucible to obtain a high-quality large single crystal with a thickness of 50mm, a width of 160mm, and a length of 180mm. Accurately orient the crystal laterally to the large surface, mechanically dig out the cylindrical crystal perpendicular to the surface, and obtain a large lithium tetraborate ingot with a diameter of 6 inches and a th...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
diameteraaaaaaaaaa
thicknessaaaaaaaaaa
diameteraaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method of lithium tetraborate piezoelectric crystal, in particular to a preparation method of large-size lithium tetraborate piezoelectric crystal. The preparation method comprises the following steps: a synthetized lithium tetraborate polycrystal material is pressed into compact cylindrical blocks; the blocks are put into a Pt crucible in which seed crystal is put in earlier and into an oven; the oven temperature is controlled to be 950 DEG C to 1000 DEG C, the descending speed of the crucible is 0.1mm / h to 0.6mm / h, and high-grade large monocrystal with thickness of 30mm to 80mm, width more than 120mm and length more than 150mm can be grown; the large monocrystal is processed in the side direction, i.e. the direct along the side with larger size serves as the axial direction of a crystal bar and the side with smaller size serves as the thickness direction of the crystal bar, and a large-size lithium tetraborate piezoelectric crystal profile is obtained. Compared with traditional descending methods, the method solves the technical bottlenecks of difficulty in inoculation, easily leaking crucible, easy cracking of the crystal and the like in the growth of large-size lithium tetraborate piezoelectric crystal through traditional descending methods, adopts sideward growth and flat crucible design, can improve the growth speed of the crystal, thereby reducing the growth difficulty of the crystal and helping to realize the industrialized growth of the large-size lithium tetraborate piezoelectric crystal.

Description

technical field [0001] The invention relates to a preparation method of a lithium tetraborate piezoelectric crystal, in particular to a preparation method of a large-size lithium tetraborate piezoelectric crystal. Background technique [0002] Piezoelectric crystals are widely used to make electronic components such as resonators, filters, and transducers, and are indispensable basic materials for modern communication and electronic technology industries. With the rapid development of the modern communication industry, the demand for piezoelectric crystals is increasing day by day, and the requirements for crystal quality and performance are also getting higher and higher. At present, the piezoelectric crystals for industrial applications mainly include α-quartz, lithium niobate, lithium tantalate, and lithium tetraborate, etc., and the newly developed gallium lanthanum silicate crystals are only used in high-temperature surface acoustic wave sensors and photoelectric sensor...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C30B29/22C30B11/00C01B35/12C01D15/00
Inventor 徐家跃
Owner SHANGHAI INST OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products