Unlock instant, AI-driven research and patent intelligence for your innovation.

Isotopic enrichment process

By using the exchange reaction of H2O-H2SiF6·nSiF4 aqueous solution and SiF4 gas in the isotope exchange reaction method, the problems of poor stability and high cost during the silicon isotope concentration process are solved, and low-cost, large-scale isotope concentration and single-unit silicon with excellent thermal conductivity are achieved. Crystalline silicon preparation.

Inactive Publication Date: 2008-09-03
STELLA CHEMIFA CORP
View PDF1 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0013] In order to solve the aforementioned existing problems, the inventors of the present application conducted research on the silicon isotope enrichment method

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0091] In this example, use image 3 The shown isotope enrichment device separates and concentrates Si isotopes. As the exchange reaction tower, use the exchange reaction tower that inner diameter 16mm, height 3000mm make exchange reaction tower 2 (the first exchange reaction tower 22 and the 2nd exchange reaction tower 22 ') configuration of fluorine resin exchange reaction tower. A fluororesin-made Rasig ring with an outer diameter of 6 mm was installed inside each exchange reaction column so that the filling height became 2500 mm. In addition, the gas absorption tower 34, the gas generation tower 27, and the gas scrubber 31 use fluororesin columns with an inner diameter of 25mm, which are the same as those used in the exchange reaction tower, and the filling heights of the Lacey rings are 600mm, 400mm, and 800mm, respectively.

[0092] First, 998.8 g of 18.9% by weight hydrofluoric acid is added to the gas absorption tower 34, and while circulating and cooling through the ...

Embodiment 2

[0098] In this example, instead of image 3 The first exchange reaction tower 22 and the second exchange reaction tower 22' of the shown isotope enrichment device use the first exchange reaction tower 41 to the eighth exchange reaction tower 48 made of fluororesin arranged in series to carry out the same process as in Example 1. The same experiment (refer to Figure 4). Each exchange reaction tower has an inner diameter of 25mm and a height of 3000mm. In addition, inside each exchange reaction tower, a fluororesin-made Rasig ring having an outer diameter of 6 mm was set to a filling height of 2500 mm. That is, the total filling height is 20m.

[0099] As a raw material, free hydrofluoric acid containing a concentration of 2.75% by weight and a high silica fluorosilicic acid (H 2 SiF 6 ·SiF 4 ) of high silica fluorosilicic acid aqueous solution. This high-silica fluorosilicic acid aqueous solution is charged into the bottoms of the first exchange reaction tower 41 to the s...

Embodiment 3

[0108] The operable composition range of saturated high silica fluorosilicic acid aqueous solution in Si isotope enrichment operation by gas-liquid contact was investigated. Hydrofluoric acid having a predetermined concentration is allowed to absorb silicon tetrafluoride gas until it becomes saturated, and the composition analysis of the saturated high silica fluorosilicic acid aqueous solution is performed. The concentration of hydrofluoric acid was 10% by weight, 15% by weight, 20% by weight, 25% by weight, 30% by weight, 35% by weight, and 40% by weight. Silicon tetrafluoride was absorbed in a closed system at 0.05 MPaG while cooling the fluororesin container to which 15.0 g of hydrofluoric acid of each concentration was added from the outside with ice water. Usually, at the beginning of absorption, the temperature of the absorption liquid rises due to heat release due to the heat of absorption, and when the saturated concentration is reached, the temperature of the absorpt...

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
heightaaaaaaaaaa
diameteraaaaaaaaaa
heightaaaaaaaaaa
Login to View More

Abstract

The present invention provides an isotope concentration method comprising the step of performing the isotope exchange between an aqueous solution containing at least two components each represented by the formula: H2O-H2SiF6SiF4 (wherein n=0) and a gas containing SiF4 to concentrate a stable Si isotope.

Description

technical field [0001] The present invention relates to a method for concentrating silicon isotopes used in the semiconductor field, the optical field, and the like. Background technique [0002] Natural silicon is composed of three stable isotopes with mass numbers of 28, 29, and 30 (hereinafter referred to as 28 Si, 29 Si, 30 Si) constitutes and exists in proportions (atomic %) of 92.23%, 4.67%, and 3.10%, respectively. [0003] It has been reported that a single crystal in which a silicon isotope is concentrated at a high concentration has a higher thermal conductivity than a natural single crystal. Therefore, silicon single crystal is highly expected as a material that contributes to higher speed, smaller size, lower power consumption, and improved stability of LSIs. Additionally, the nuclear spin 29 Silicon, from which Si is completely removed, is the closest material to the realization of a quantum computer capable of ultrahigh-speed calculations. [0004] In ord...

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): B01D59/32C01B33/02C01B33/107
CPCB01D59/32C01B33/103C01B33/107Y10S423/07C01B33/02
Owner STELLA CHEMIFA CORP