Diffusion barriers prevent molecules from spreading and contaminating products. They are usually thin coatings made of metals with non-reactive and adhesive properties. They are commonly used in electronics manufacturing to preserve copper wiring from silica insulation. New alloys and deposition techniques are being investigated for use in new generations of electronics.
A diffusion barrier is usually a thin coating of material used to prevent spread. Diffusion occurs when molecules move from an area of high concentration to an area of low concentration so that equal numbers occur in both areas. Diffusion occurs whether the molecules are in a gaseous, liquid or solid state and can lead to contamination of one product by another.
A diffusion barrier is usually only micrometers thin and is used to improve the shelf life of metal-containing products by slowing their corruption by other nearby products. These types of barriers are used in a variety of commercial applications, so effective and cost-effective barriers are highly sought after, especially by the electronics industry. While there are diffusion barriers for oxygen and hydrogen gas, most of the diffusion barriers are metals.
A good diffusion barrier has physical and chemical properties that vary depending on the metallic components used to make the barrier. The thinner the diffusion barrier and the more uniform the coating, the more effective the barrier. The metals in the barrier must be non-reactive to surrounding materials, so they do not spread and corrode the metals the barrier is intended to protect. Furthermore, the diffusion barrier must be able to adhere strongly to what it is protecting to provide a secure barrier that completely prevents any molecule from diffusing.
The different materials used to make diffusion barriers offer different benefits, and care must be taken to optimize the barrier’s thickness, reactivity, and adhesion. Metals differ in their reactivity and adhesion, with some metals providing a high degree of unreactivity but low adhesion, or vice versa. Some barriers may have multiple layers to accommodate the need for both non-reactive and adhesive metals. Alternatively, a combination of metals, called alloys, can be used to form the barrier. A number of metals have been used in creating diffusion barriers, including aluminum, chromium, nickel, tungsten, and manganese.
Diffusion barriers have been commonly used in electronics manufacturing for decades. They are used to preserve the integrity of the internal copper wiring from the surrounding silica insulation. This is to extend the life of the electronic device by preventing circuit failure that would occur if the copper and silica came into contact. Until now, the technology to create and deposit barriers to diffusion has allowed consumer electronics to go faster; however, new alloys and barrier deposition techniques are being investigated for use in new generations of electronics.
Protect your devices with Threat Protection by NordVPN
