A definition in semiconductor physics, carrier lifetime is defined as the average time it takes for a minority carrier to recombine. The process through which this is done is typically known as minority carrier recombination.
The energy released due to recombination can be either thermal, thereby heating up the semiconductor (thermal recombination or non-radiative recombination, one of the sources of waste heat in semiconductors), or released as photons (optical recombination, used in LEDs and semiconductor lasers).
Carrier lifetime plays an important role in bipolar transistors and solar cells.
In indirect band gap semiconductors, the carrier lifetime strongly depends on the concentration of recombination centers. Gold atoms act as highly efficient recombination centers, silicon for some high switching speed diodes and transistors is therefore alloyed with a small amount of gold. Many other atoms, e.g. iron or nickel, have similar effect.
Read more about Carrier Lifetime: Carrier Lifetime in Semiconductor Lasers
Famous quotes containing the words carrier and/or lifetime:
“We know what the animals do, what are the needs of the beaver, the bear, the salmon, and other creatures, because long ago men married them and acquired this knowledge from their animal wives. Today the priests say we lie, but we know better.”
—native American belief, quoted by D. Jenness in “The Carrier Indians of the Bulkley River,” Bulletin no. 133, Bureau of American Ethnology (1943)
“The individual, the great artist when he comes, uses everything that has been discovered or known about his art up to that point, being able to accept or reject in a time so short it seems that the knowledge was born with him, rather than that he takes instantly what it takes the ordinary man a lifetime to know, and then the great artist goes beyond what has been done or known and makes something of his own.”
—Ernest Hemingway (1899–1961)