Definition: GAAFET

(Gate All Around Field Effect Transistor) Emerging in the mid-2020s, the GAAFET transistor technology follows FinFET for high-end chips such as 2 nm and below. In FinFET, the gate surrounds three sides of the channel between source and drain, but GAAFET gates surround all four sides for higher performance and better control. Pronounced "gah-fet," the GAAFET manufacturing process is more complicated (see below).

However, gate architecture is only one part of transistor evolution. Other factors are the type of materials used, how transistors are wired together, how power is delivered and the lithographic methods used (see EUV light). Chip packaging is also an important part of chip evolution (see chip package).

Planar -> FinFET -> GAAFET -> CFET

In early planar transistors, the gate resided over the channel between source and drain. FinFET gates wrap around three sides, but GAAFET gates completely surround the channel. The nanowire variety is yet to be commercialized but GAAFET nanosheets are state of the art. In time, CFETs are expected to replace GAAFETs (see CFET). See nanosheet. (Top image courtesy of Intel.)