A wafer is a thin slice of semiconductor material, such as a silicon crystal

Monocrystalline silicon

Monocrystalline silicon or single-crystal Si, or mono-Si is the base material of the electronic industry. It consists of silicon in which the crystal lattice of the entire solid is continuous, unbroken to its edges. It can be prepared intrinsic, i.e...

, used in the fabrication

Semiconductor fabrication

Semiconductor device fabrication is the process used to create the integrated circuits that are present in everyday electrical and electronic devices. It is a multiple-step sequence of photolithographic and chemical processing steps during which electronic circuits are gradually created on a wafer...

 of integrated circuits and other microdevices. The wafer serves as the substrate

Substrate (semiconductor)

Substrate is a solid substance onto which a layer of another substance is applied, and to which that second substance adheres. In solid-state electronics, this term refers to a thin slice of material such as silicon, silicon dioxide, aluminum oxide, sapphire, germanium, gallium arsenide , an alloy...

 for microelectronic devices built in and over the wafer and undergoes many microfabrication

Microfabrication

Microfabrication is the term that describes processes of fabrication of miniature structures, of micrometre sizes and smaller. Historically the earliest microfabrication processes were used for integrated circuit fabrication, also known as "semiconductor manufacturing" or "semiconductor device...

 process steps such as doping or ion implantation

Ion implantation

Ion implantation is a materials engineering process by which ions of a material are accelerated in an electrical field and impacted into another solid. This process is used to change the physical, chemical, or electrical properties of the solid...

, etching

Etching (microfabrication)

Etching is used in microfabrication to chemically remove layers from the surface of a wafer during manufacturing. Etching is a critically important process module, and every wafer undergoes many etching steps before it is complete....

, deposition of various materials, and photolithographic

Photolithography

Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...

 patterning. Finally the individual microcircuits are separated (dicing

Wafer dicing

Wafer dicing is the process by which die are separated from a wafer of semiconductor following the processing of the wafer. The dicing process can be accomplished by scribing and breaking, by mechanical sawing or by laser cutting...

) and packaged

Integrated circuit packaging

Integrated circuit packaging is the final stage of semiconductor device fabrication per se, followed by IC testing.Packaging in ceramic or plastic prevents physical damage and corrosion and supports the electrical contacts required to assemble the integrated circuit into a system.In the integrated...

.

Several types of solar cell

Solar cell

A solar cell is a solid state electrical device that converts the energy of light directly into electricity by the photovoltaic effect....

 are also made from such wafers.