Plasma
A plasma is one of the four states of matter. It is similar to a gas, but consists of positively charged ions with most or all of their detached electrons moving freely. Plasmas are produced by very high temperatures, as in the sun and other stars, and also by the ionization resulting from exposure of a material to a dense electron current, such as an arc (spark). The energy level of plasma is determined chiefly by the gas density and the energy input level.
Resist
Resists are generally proprietary mixtures of a polymer or its precursor and other small molecules (e.g. photoacid generators) that have been specially formulated for a given lithography technology. The viscous polymer resists used during photolithography are called photoresists.
Scanner
(Stepper) The detailed patterns in semiconductor device fabrication are transferred using a type of stepper called a scanner, which moves the wafer and photomask with respect to each other during the exposure to increase the size of the area exposed. Elements of the circuit to be created on the IC are reproduced in a pattern of transparent and opaque areas on the surface of a plate called a photomask. The stepper passes light through the reticle, forming an image of the photomask pattern. The image is focused and reduced by a lens, and projected onto the surface of a silicon wafer that is coated with a photosensitive material called a photoresist.
Wafer
A wafer is a thin circular slice of a material such as pure silicon that has been doped to produce a semiconducting material on which an integrated circuit can be formed.