Date:1 February 2011
One of the rarest metals on Earth may be an excellent option for enabling future flash memory chips to continue to increase in speed and density, according to a group of researchers in Taiwan.
The team chose iridium – a hard, dense and corrosion resistant metal in the platinum family, and one of the rarest metals found in the earth’s crust – because unlike most alternatives, it has two desired properties: it holds its electrons strongly, and its melting point of nearly 2 500 degrees Celsius is well beyond the 900-degree annealing temperature that many chips must survive during manufacturing. Fortunately, only a billionth of a billionth of a gram of iridium would be needed for each gate.
“Incorporating nanocrystals of iridium into the critical floating gate portion of flash memory designs shows both excellent memory properties as well as stability in the high temperatures used in processing such semiconductor devices,” says the research team leader, Wen-Shou Tseng.
Source: American Institute of Physics