Analysis of common evaporation coating technology- Ningbo Danko Vacuum Technology Co., Ltd.

Analysis of common evaporation coating technology

1. Resistance evaporation plating: The resistance evaporation source is used to evaporate low melting point materials, such as gold, silver, zinc sulfide, magnesium fluoride, chromium trioxide, etc. Resistance evaporation sources are generally made of tungsten, molybdenum and tantalum.

2. Electron beam evaporation plating: After the film material is vaporized and evaporated by electron beam heating, it is condensed on the surface of the substrate to form a film, which is an important heating method in vacuum evaporation technology.

There are many types of such devices. With the wide application of thin film technology, not only the requirements for the types of membranes are various, but also the requirements for the quality of the membranes are more stringent.

Resistance evaporation can no longer meet the needs of evaporation of some metals and non-metals. The electron beam heat source can obtain a much larger energy density than the resistance heat source, and the value can reach 104-109w/cm2, so the film can be heated to 3000-6000c.

This provides a better heat source for evaporating refractory metals and non-metallic materials such as tungsten, molybdenum, germanium, SiO2, AI2O3, etc. Moreover, since the material to be evaporated is placed in a water-cooled crucible, the evaporation of the container material and the reaction between the container material and the film material can be avoided, which is important for improving the purity of the film.

In addition, heat can be directly added to the surface of the film material, so the thermal efficiency is high, and the heat conduction and heat radiation losses are small.

3. Arc heating evaporation plating: A heating method similar to the electron beam heating method is the arc discharge heating method. It also has the characteristics of avoiding the contamination of resistance heating materials or crucible materials, and has the characteristics of high heating temperature, especially suitable for the evaporation of refractory metals, graphite, etc. with high melting point and certain conductivity.

At the same time, the equipment used in this method is simpler than that of the electron beam heating device, so it is a relatively inexpensive evaporation device.

4. Laser beam evaporation plating: The method of using high power density pulsed laser to evaporate materials to form thin films is generally called laser evaporation

5. High-frequency induction heating evaporation plating: use the principle of induction heating to heat the metal to the evaporation temperature.

The crucible containing the film material is placed in the center of the spiral coil, and a high-frequency current is passed through the coil, so that the metal film material can generate current to heat itself up until it evaporates.

Features of induction heating evaporation source:

1. High evaporation rate

2. The temperature of the evaporation source is uniform and stable, and it is not easy to produce aluminum drop splash phenomenon

3. The evaporation source is charged at one time, no wire feeding mechanism is required, the temperature control is relatively easy, and the operation is simple

4. The requirements for the purity of the membrane material are slightly wider.

Thermal Evaporation Vacuum Coating Machine