Thin film

Thin films are thin material layers ranging from fractions of a nanometre to several micrometres in thickness. Electronic semiconductor devices and optical coatings are the main applications benefiting from thin film construction. Some work is being done with ferromagnetic thin films as well for use as computer memory.

Additional recommended knowledge

Essential Laboratory Skills Guide

Weighing the right way

What is the Correct Way to Check Repeatability in Balances?

Ceramic thin films are also in wide use. The relatively high hardness and inertness of ceramic materials make this type of thin coating of interest for protection of substrate materials against corrosion, oxidation and wear. In particular, the use of such coatings on cutting tools may extend the life of these items by several orders of magnitude.

Thin-film technologies are also being developed as a means of substantially reducing the cost of photovoltaic (PV) systems. The rationale for this is that thin-film modules are expected to be cheaper to manufacture owing to their reduced material costs, energy costs, handling costs and capital costs. However, thin films have had to be developed using new semiconductor materials, including amorphous silicon, copper indium diselenide, cadmium telluride and film crystalline silicon. In all cases, these technologies face major technical and financial hurdles.

The engineering of thin films is complicated by the fact that their physics is in some cases not well understood. In particular, the problem of dewetting may be hard to solve, as there is ongoing debate and research into some processes by which this may occur.

High precision thin film deposition on large substrates

  One of the major barriers met in thin film deposition is the ability to coat large dimension substrates whilst obtaining high precision results with mono or multi-layer deposition. The HiTUS plasma sputter deposition technology together with the Linear Target technology has demonstrated major improvements in desired results such as precision, uniformity, stress control from compressive to tensile with zero in between, and roughness on substrates measuring up to and over and above 50 to 60 cm. The Linear Target also enables the development of a large area linear process with the same advantages as HiTUS for roll-to-roll or in-line processes.

Techniques

• Thin-film deposition in CBD (Chemical Bath Deposition) method
• Physical vapor deposition (PVD)
  • Thermal Evaporation
  • Electron Beam deposition
  • Sputtering
  • Pulsed laser deposition
  • Cathodic Arc Deposition
• Chemical vapor deposition
  • Plasma Enhanced Chemical Vapor Deposition (PECVD)
  • Atomic Layer Deposition (ALD)
• Molecular beam epitaxy
• Sol-Gel Process
• Spin coating

Metallo-organic decomposition (MOD)

See also

• Thin-film deposition
• Thin-film optics
  • Dispersion (optics)
• Thin-film transistor
• Thin film memory
• Scratch tester, a method of testing thin film adhesion
• Calo tester, a method of measuring thin film thickness
• Pin on disc tester, a method of testing friction and wear resistance of thin films
• Thin liquid film, a liquid of small height flowing on a surface