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.

Work is being done with ferromagnetic thin films for use as computer memory. It is also being applied to pharmaceuticals, via thin film drug delivery. Thin-films are used to produce thin-film batteries.^[1]

Ceramic thin films are 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 can extend the life of these items by several orders of magnitude.

Research is being done on a new class of thin film inorganic oxide materials, called amorphus heavy-metal cation multicomponent oxide, which could be used to make transparent transistors that are inexpensive, stable, and environmentally benign ^[2].

Thin-films are applied to surfaces using one of many techniques of thin-film 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, specially represented in the used of printed electronics processes.

Thin-films solar cells consist of plastic or other substrates coated with silicon (i.e. amorphous silicon) or other photovoltaic material.

These technologies face major technical hurdles. Laboratory tests have shown efficiencies of up to 19.9 percent for CIGS cells, compared with a record of about 16.5 percent for cadmium telluride. But the reality outside of the labs (commercial photovoltaic panels) has been different. So far, First Solar has reached average cell efficiencies of 10.6 percent.^[3]

Light-absorving materials in thin-film photovoltaic cells are:

• Cadmium telluride (CdTe)
• Copper indium (Gallium) (di)Selenide (CIS and CIGS)
• Dye
• Organic materials.
• Silicon:
  • Amorphous silicon(a-Si) and [[nanocrystalline silicon(nc-Si) or microcrystalline silicon(uc-Si) (that can be combined in micromorphous silicon(a-Si/nc-Si) or (a-Si/uc-Si)).
  • Black silicon

Thin-film solar cell manufacturing is poised to make a giant leap in scale with the birth of the gigawatt fab ^[4]. First Solar (CdTe) is the largest manufacturer of thin-film cells in the world^[5], with production capacity expected to reach over 435 MW by the end of 2008.(Plan for 1GW in 2009)

• Sharp Corp (a-Si,Tandem production) expects to begin production at a 1GW thin-film plant in Japan in 2010.
• NexPower Technology (Taiwan)(a-Si,Tandem production)
• Kaneka (Japan)(a-Si,Tandem production)
• MHI (Japan)(a-Si,Tandem production)
• Sanyo (Japan) (a-Si)
• Uni-Solar (US)(a-Si,Triple Junction production)
• Ersol (German)(a-Si)(Oerlikon)
• Sun well (Taiwan)(a-Si)(Oerlikon)
• Inventux (German)(a-Si,Tandem production))(Oerlikon)
• Signet Solar (German)(a-Si)(Applied Materials)
• Moser Baer (India)(a-Si)(Applied Materials)
• Suntech (China)(a-Si)(Applied Materials)
• First Solar (US)(CdTe)
• Global Solar (German)(CIGS)
• Honda (Japan)(CIGS)
• Wurth Solar (German)CIS
• Honda Soltec(Japan)CIGS
• Global Solar (US)CIGS
• Showa Shell Solar (Japan)CIS
• Miasole (US)CIGS
• Johanna Solar (German) CIGSSe
• Odersun(China ATMCN)(German)CISCut
• Solibro Solar(German)CIGS
• Sulfurcell (German)CIS
• AVANCIS(Shell Solar)(German)CIS
• HelioVolt (US)CIGS
• Ascent Solar(US)CIGS
• DayStar (US) CIGS
• Nanosolar (US) CIGS
• SoloPower (US)CIGS
• [[ISET(US)CIS
• Siemens Solar (copper indium diselenide)
• Quantum Solar Systems (quantum dot polymer solar cells) ^[6].
• BP Solar (amorphous silicon, cadmium telluride)
• Odersun with the capacity to produce 30 megawatts of thin films.

• Ellipsometry
• Hydrogenography
• Thin-film optics
• Thick film

• 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