Production process of gas purification

Production process of gas purification

There are many ways to classify special gases. For example, according to the chemical composition of gases, they can be divided into seven categories: silicon series, arsenic series, phosphorus series, boron series, metal hydride, halide and metal hydrocarbon. According to its role in integrated circuits, it can be divided into seven types: doping gas, epitaxial gas, ion implantation gas, light emitting diode gas, etching gas, chemical vapor deposition (CVD) gas and carrier dilution gas. At the same time, the above classifications are crossed, for example, silicon tetrachloride (SiCl4) is both a silicon gas and an epitaxial gas, and also has applications in chemical vapor deposition (CVD).

The main production processes of special gases include gas synthesis, gas purification, gas mixing, gas cylinder treatment, gas filling, gas analysis and detection. Gas synthesis is the chemical reaction of raw materials under specific pressure, temperature, catalyst and other conditions to obtain gas crude products. Gas purification is to refine crude products into higher purity products through distillation, adsorption and other methods.

What is purification

Gas mixing is to mix two or more effective component gases in a specific proportion to obtain a multi-component gas mixture with uniform distribution.

Gas cylinder treatment refers to the process of treating the inner, inner wall surface and appearance of the gas cylinder according to the nature and demand of the carrier gas to ensure the stability of the product during gas storage and transportation. Gas filling refers to filling gas into pressure vessels such as gas cylinders through pressure difference; Gas analysis and detection is the process of analyzing and detecting the composition of gas.

Impurities such as water vapor and oxygen in the electronic special gas are easy to form oxide film on the semiconductor surface, affecting the service life of electronic devices, and the particle impurities contained will cause semiconductor short circuit and circuit damage.

With the continuous development of semiconductor industry, the production accuracy of products is getting higher and higher. Taking integrated circuit manufacturing as an example, its circuit linewidth has changed from the millimeter level at the beginning of Z to the micron level or even the nanometer level, which also puts forward higher requirements for the purity of electronic special gases used in semiconductor production.