Thin films continue to attract the attention of researchers. This article presents current and more in-depth research on their applications, variable deposition methods, and future uses.
“Film” is a relative term for a two-dimensional (2D) material that is much thinner than its substrate, whether it is intended to cover the substrate or be sandwiched between two surfaces. In current industrial applications, the thickness of these thin films typically ranges from sub-nanometer (nm) atomic dimensions (i.e., <1 nm) to several micrometers (μm). Single-layer graphene has a thickness of one carbon atom (i.e. ~0.335 nm).
Films were used for decorative and pictorial purposes in prehistoric times. Today, luxury items and jewelry are coated with thin films of precious metals such as bronze, silver, gold and platinum.
The most common application of films is the physical protection of surfaces from abrasion, impact, scratches, erosion and abrasions. Diamond-like carbon (DLC) and MoSi2 layers are used to protect automotive engines from wear and high temperature corrosion caused by friction between mechanical moving parts.
Thin films are also used to protect reactive surfaces from the environment, whether it be oxidation or hydration due to moisture. Shielding conductive films have received much attention in the fields of semiconductor devices, dielectric film separators, thin film electrodes, and electromagnetic interference (EMI). In particular, metal oxide field effect transistors (MOSFETs) contain chemically and thermally stable dielectric films such as SiO2, and complementary metal oxide semiconductors (CMOS) contain conductive copper films.
Thin-film electrodes increase the ratio of energy density to the volume of supercapacitors by several times. In addition, metal thin films and currently MXenes (transition metal carbides, nitrides or carbonitrides) perovskite ceramic thin films are widely used to shield electronic components from electromagnetic interference.
In PVD, the target material is vaporized and transferred to a vacuum chamber containing the substrate. Vapors begin to deposit on the surface of the substrate simply due to condensation. The vacuum prevents mixing of impurities and collisions between vapor molecules and residual gas molecules.
The turbulence introduced into the steam, the temperature gradient, the steam flow rate, and the latent heat of the target material play an important role in determining film uniformity and processing time. Evaporation methods include resistive heating, electron beam heating and, more recently, molecular beam epitaxy.
The disadvantages of conventional PVD are its inability to vaporize very high melting point materials and the structural changes induced in the deposited material due to the evaporation-condensation process. Magnetron sputtering is the next generation physical deposition technique that solves these problems. In magnetron sputtering, target molecules are ejected (sputtered) by bombardment with energetic positive ions through a magnetic field generated by a magnetron.
Thin films occupy a special place in modern electronic, optical, mechanical, photonic, thermal and magnetic devices and even decor items due to their versatility, compactness and functional properties. PVD and CVD are the most commonly used vapor deposition methods to produce thin films ranging in thickness from a few nanometers to a few micrometers.
The final morphology of the deposited film affects its performance and efficiency. However, thin film evaporative deposition techniques require further research to accurately predict thin film properties based on available process inputs, selected target materials, and substrate properties.
The global semiconductor market has entered an exciting period. Demand for chip technology has both spurred and retarded the development of the industry, and the current chip shortage is expected to continue for some time. Current trends are likely to shape the future of the industry as this continues
The main difference between graphene-based batteries and solid-state batteries is the composition of the electrodes. Although cathodes are often modified, allotropes of carbon can also be used to make anodes.
In recent years, the Internet of Things has been rapidly implemented in almost all areas, but it is especially important in the electric vehicle industry.
Post time: Apr-23-2023