Dewar structure with functions of detection and safety protection

Abstract

The invention relates to a Dewar structure with the functions of detection and safety protection. The Dewar structure is characterized by comprising a Dewar tank body, wherein an inner cavity which is isolated from the outside is formed in the Dewar tank body; an injection port and an exhaust port are formed in the Dewar tank body, a low-temperature liquid medium is injected to the inner cavity from the injection port, and a gas in the inner cavity is discharged from the exhaust port; a cold trap adapter interface used for connecting a cold trap is arranged on the Dewar tank body; and a state detection system used for detecting the pressure of the inner cavity and the liquid-level height of the low-temperature liquid medium and a pressure relief system used for discharging excessive pressure of the inner cavity are arranged on the Dewar tank body. The Dewar structure with the functions of detection and safety protection, disclosed by the invention, is used for performing exhaust gas treatment in material deposition, growth and processing equipment, can reduce the volatilization of the low-temperature liquid medium and avoids safety problems caused by freezing.

Description

technical field [0001] The invention relates to a Dewar structure, in particular to a Dewar structure with detection and safety protection. Background technique [0002] The material deposition, growth and processing equipment belongs to the vacuum system. The vapor exhaust gas from the material deposition, growth and processing process will corrode and damage the subsequent pipeline and vacuum pump, and the return of oil vapor from the oil-sealed vacuum pump to the vacuum reaction chamber will also affect the product. . Therefore, it is necessary to use cold traps and other devices to condense the reaction tail gas and oil vapor to ensure the normality of the process and equipment. The lower the cooling temperature of the cold trap, the better the trapping effect on reaction tail gas and oil vapor, so it is generally used in conjunction with Dewar, and the low-temperature refrigeration medium is usually liquid gas such as liquid nitrogen. [0003] The conventional Dewar s...

AI Technical Summary

Problems solved by technology

However, this standard Dewar structure still has many defects, such as poor thermal insulation performance, low-temperature liquid medium is easy to volatilize, and there will be a safety hazard of freezing at the exposure in a high-humidity environment, which cannot be released, and it is not convenient to use with a cold trap.

[0004] When the cold trap is placed in the Dewar flask, the upper opening cannot be completely sealed, and the opening is still in contact with the atmosphere. The low-temperature liquid medium is easy to undergo heat exchange and volatilize, and at the same time, the moisture in the atmosphere will condense into ice at the cold wall of the opening. Gradually block the channel for the volatilization of liquid nitrogen in the Dewar vessel, causing the pressure to fail to release normally, and the increase in the internal pressure of the Dewar vessel will pose a safety hazard

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