In the production process of electronic devices. Various high purity gases are widely used. According to the different uses of high purity gas in the process, it can be divided into protective gas, reaction gas and carrier gas.

Protective gases are hydrogen, nitrogen, oxygen and their mixtures. In order to obtain hydrogen and ammonia in China, in order to obtain high purity hydrogen, the method of electrolysis pure water is generally used to produce. This method requires a large amount of electric energy to electrolysis water, generally 4.5~ 5.5kWh/nm3H2, which leads to high cost.

In order to reduce power consumption and cost, various mixtures are being developed and applied. Among them, nitrogen-hydrogen mixture is the most used. The mixture of nitrogen and hydrogen is obtained by vaporization of liquid hydrogen and liquid nitrogen, and the mixture of nitrogen and hydrogen is obtained by decomposition of liquid nitrogen.

Nitrogen and Hydrogen mixture gas

The method of obtaining nitrogen-oxygen mixture by vaporization of liquid hydrogen and liquid nitrogen has higher investment and cost because it adopts the process of liquefaction and vaporization. In foreign countries, because of the high degree of specialization in production, the use of units mostly adopt this method to obtain the mixture. Domestic production of liquid hydrogen and nitrogen from by-products of specialized plants or large conglomerates costs several times more than hydrogen and chlorine from electrolysis and "air separation" of nitrogen. Due to the different sources of liquid nitrogen, most of the nitrogen-oxygen mixture obtained by the decomposition of liquid ammonia is of poor quality, and it still contains impurities such as undecomposed ammonia, water and oxygen. In addition, liquid nitrogen mostly comes from fertilizer plants. At present, the supply is relatively tight, so the cost is higher.

Nitrogen and hydrogen mixture can not only replace oxygen as protective gas in the production of electronic devices, but also can be widely used in metallurgy, chemical industry, machinery and other industries. Once widely popularized and applied, it will surely produce considerable economic and social benefits.