Principle of Sputtering Thin Film Deposition Technology

Sputtering deposition is a physical vapor deposition technique that uses high-energy particles to bombard targets and eject particles from solid targets. This is an electronic process of depositing thin films of metals or other materials onto various surfaces. The most common is that sputtering is used to apply thin coatings on silicon wafers, solar panels, and displays.

The working principle of sputtering deposition

Sputtering deposition is carried out in a vacuum chamber, where inert gas is introduced, most commonly argon ions. There are two items placed in the room: the item to be electroplated, also known as the "substrate", and the material to be coated, also known as the "sputtering target". After argon ion ionization, kinetic energy is obtained under electric field acceleration to bombard the target. Atomic migration on the surface of the target material can only be achieved when the energy of argon ions reaches the binding energy of the target electrode (approximately the sublimation heat of the target material). When the energy of the bombarding particles exceeds four times the sublimation heat of the target material, the atoms are pushed out of the lattice position, transformed into a gas phase, escaped from the target material, and move towards the coating material. This process is called sputtering. For most metals, the sputtering threshold energy is approximately 10 to 25 electron volts.

In short, the basic principle of sputtering deposition can be divided into three process steps
1. Electroplating material gasification: sputtering;
2. Migration of electroplated atoms, molecules, or ions: Various reactions occur after atomic, molecular, or ion collisions;
3. Electroplating atoms, molecules, or ions onto the substrate.

advantage
The characteristics of sputtering deposition are: 1. Good durability, the thin film obtained by sputtering deposition is sometimes harder and more corrosion-resistant;
2. Widely applicable, almost all types of inorganic and partially organic coating materials can be used for multiple groups of substrates and surfaces with various finishes;
3. Environmentally friendly, as the sputtering deposition process occurs in a vacuum environment, it is more environmentally friendly than other traditional coating technologies such as electroplating and spray painting. And the sputtering process will not produce toxic gases such as CO or SO2;
4. Easy to clean, it can save the time and cost of cleaning and polishing general copper (gold) products. Simply use a soft cloth or glass cleaner to clean the sputtering coating;
5. High quality with multiple choices, diverse colors of sputtered film, delicate and smooth surface, rich metallic luster, never fading. Common colors include gold (TiN), bright silver (CrN), purple (TiAlN), etc.