A test device for thin film deposition and catalytic reaction of volatile corrosive substances under ultra-high vacuum conditions

Abstract

The invention relates to a test device for volatile and corrosive substance thin film deposition and catalytic reaction based on ultra-high vacuum conditions. The sample console, evaporation source, etc. can be used for the deposition of volatile and corrosive substances. The test device includes a reaction chamber and a fast sampling chamber. The reaction chamber includes a temperature-controlled sample stage. The sample heating source is relatively local replaceable, which can reduce the background interference in the reaction and realize accurate catalytic reaction activity testing at different temperatures. The chamber The extracorporeal components include an air intake system, which can be fed with a chemical reaction gas. The invention is applicable to the preparation of films of various volatile and corrosive substances, and is connected with various ultra-high vacuum analysis instruments to realize accurate testing of catalyst reactivity.

Description

technical field [0001] The invention relates to a test device for thin film deposition and catalytic reaction of volatile corrosive substances under ultra-high vacuum conditions, and belongs to the technical field of thin film deposition and catalytic activity testing. Background technique [0002] Generally speaking, the growth and preparation process of thin films is usually grown by molecular beam epitaxy. It is necessary to evaporate the precursor of the target element to the gaseous state, and then deposit it on the surface of the sample by molecular beam sputtering in a certain chemical atmosphere. Then analyze the surface structure. Using sophisticated surface instruments operating under ultra-high vacuum conditions, such as photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), Auger electron spectroscopy (AES) and scanning tunneling microscopy (STM), the atomic structure of thin films can be obtained A clear and exact pointer can provide valuable...

AI Technical Summary

Problems solved by technology

The reason is that these volatile compounds have a very high vapor pressure at a lower temperature, which will cause the entire ultra-high vacuum chamber to be easily polluted by volatile substances. On the other hand, the corrosive gas that needs to be introduced, Has a strong corrosive effect on electronic and metal components

The combined action of the two leads to the destruction and difficulty of maintaining ultra-high vacuum, and also causes irreversible failures such as circuit short circuit and pollution in vacuum precision instruments.

This makes the preparation of volatile compounds and the precise analysis of the surface structure very difficult, and also restricts the progress of material characterization and synthesis preparation technology

[0004] On the other hand, many surface analysis techniques can give precise structural information on the surface, but they can only operate in the ultra-high vacuum range, while conventional chemical processes are at close to atmospheric pressure or higher pressure

This makes it impossible to test catalytic reactions in ultra-high vacuum systems

However, the existing commercial catalytic reaction chambers usually use radiation sources for integral heating, which will cause the background of the chamber to be heated together, resulting in serious uncontrollable background pollution.

These background contaminations are likely to alter the reactivity of clean test samples, thus causing inaccurate activity measurements

This also makes it difficult to directly correlate the obtained sample surface structure information with the activity of the catalytic reaction, which also restricts the exact correlation between the structure and performance of the catalyst sample.

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