Aluminum nitride powder extraction method

1) Direct nitriding of aluminum powder

ALN+N2→2ALN Put the aluminum powder into a reaction furnace filled with nitrogen and ammonia and heat it to 600°C to start the reaction. We can synthesize a large amount of ALN powder with higher purity, and currently there is large-scale production in this way. However, this method is generally difficult to obtain aluminum nitride powder with fine particles and uniform particle size, and usually requires post-treatment. In addition, the formation of an ALN layer on the surface of the AL particles will hinder the diffusion of nitrogen to the center of the particles. Therefore, the conversion rate of this method is an important issue.

2) Carbothermal reduction of alumina

The method Al203+3C+N2→2AlN+3CO is currently the most widely used in industrial production, and its research is more in-depth.

In this method, calcium oxide, calcium fluoride, yttrium oxide, etc. are often added as catalysts in the preparation of aluminum nitride powder. The addition of calcium fluoride is more effective in reducing the activation energy and increasing the reaction rate. The prepared aluminum nitride powder has high purity, good forming and sintering performance, but high synthesis temperature, long reaction time, and large powder particle size.

It needs to be explained here. If you have a small partner who understands the gold wire bonding process, it will be clearer. The rougher surface has obvious grainy aluminum nitride. If you use this type of aluminum nitride sputtering thin film metal, you will It is not easy to bond, especially the ball bonding process, it is prone to desoldering conditions.