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. It is also being applied to pharmaceuticals, via thin film drug delivery.

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.

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.

Physical vapor deposition (PVD) refers to a variety of vacuum deposition techniques that deposit thin films by the condensation of vaporized material onto a substrate. The coating material can be evaporated thermally, or by laser or electron bombardment. PVD can be used to deposit metals, alloys, ceramics, composites and multilayers.

• Thermal Evaporation
• Electron beam physical vapor deposition
• Sputtering
• Pulsed laser deposition
• Cathodic Arc Deposition

Chemical vapor deposition uses vapor phase chemical reaction to deposit thin film on a substrate.

• Chemical vapor deposition
• Plasma Enhanced Chemical Vapor Deposition (PECVD)
• Metalorganic chemical vapor deposition
• Hybrid Physical-Chemical Vapor Deposition

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.

A flexible battery has thin-solar cells which are held inside a flexible gas barrier to prevent them from degrading when exposed to air. At just two grams in weight and just one millimetre thick, the flexible battery is small enough to be used in low-wattage gadgets - including flat smart cards and mobile phones ^[1].

Research Institutes and Universities involved with thin film photovoltaic technologies: ^[2]

• Avanced technology Institute - University of Surrey (UK)
• AIST - National Institute of Advanced Industrial Science and Technology
• Arizona State University
• Colorado State University
• École Polytechnique Fédérale de Lausanne
• Florida Solar Energy Centre
• Fraunhofer ISE
• Helsinki University of Technology (TKK)
• IMEC
• Imperial College London
• Idaho National Laboratory (INL)
• KAIST - Korean Advanced Institute of Science and Technology
• Lawrence Berkeley National Laboratory
• Massachusetts Institute of Technology (MIT)
• National Renewable Energy Laboratory (NREL)
• University of Delaware - Institute of Energy Conversion (IEC)

2008 will be the breakout year for thin film solar^[3] .

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.

• Atomic Layer Deposition (ALD)
• Copper indium gallium selenide (CIGS)
• Condensed Vapour Deposition
• Electrodeposition
• Flame Hydrolysis Deposition
• Konarka
• Molecular beam epitaxy
• p-n junction
• Seeding technology
• Sol-Gel Process
• Solar cell
• Spin coating
• Carbon nanotubes in photovoltaics
• Sputter deposition
• Thin-film deposition in CBD (Chemical Bath Deposition) method

• Thin-Film Solar Has Bright Future.
• Thin-Film Solar Set to Take Market Share From Crystalline Solar PV: worldwide thin-film solar production will grow eightfold by 2010, with amorphous silicon leading the way.
• The Thin Film Solar Revolution