The basic sputtering process consists of depositing metals, plastics, and ceramics into a target, or a substrate. During this process the high vacuum environment condenses ejected atoms from the materials and forms a thin film. Before the film is even layered upon the material, the ejected atoms need to travel a certain distance within the system to be able to begin the condensation process. This is where an enhanced form of sputtering, which is discussed below, maximizes the efficiency of the entire process and reduces the margin for error. While the concept of this process sounds particularly easy, the actual mechanism is very complex.
Magnetron Sputtering Process
To enhance the basic sputtering process of a substrate, a strong magnetic field is utilized near the targeted area. This is what is known as a magnetron sputtering system. The advantage of this compared to the basic sputtering system is the potential damage of the thin film being produced reduces substantially due to the electrons travelling around the targeted area rather than directly at the target. Why is this a much safer approach? With the plasma confined in a place close to, but not directly on the target, the thin film won’t be in a position where it can produce a damaged result.
Another advantage to this type of sputter deposition is that there is a much larger field that the electrons need to travel for the ionization of atoms. By doing so, there is a higher density of ions and the plasma winds up becoming exponentially more stable in the end. The sputtering process is affected in a more efficient way, therefore creating a solid thin film. Minimizing the amount of impurities and stray ions is an important factor for the deposition process. Thin film needs to be free of these impurities and the magnetron sputtering process gives way to that.
While every system has its advantages, there are also its shortcomings as well. One of them is that there is a limited capability for the use of target materials being magnetized. With an interference of the magnetic field the target material’s magnetic nature must not affect the efficiency of the system. This is why non-magnetic materials are used. On the other hand, new technological improvements are giving way to sputtering guns that can handle the magnetic incongruities while still producing a superior solution.
Summing it all up
Magnetron sputtering systems have proven to handle deposition processes with more efficiency. By introducing magnetic fields into the picture, thin films are created with fewer impurities and more stability. Compared to ion beam deposition techniques, magnetron sputtering utilizes the magnetic fields to their advantage which in the long run can be a better option for you.
Denton Vacuum, LLC manufactures systems for vacuum deposition for electron microscopy, electronics, and ophthalmic applications.