NIST finds nano clue to better semiconductor
- By Patrick Marshall
- Dec 17, 2007
Researchers at the National Institute of Standards and Technology have identified one of the obstacles on the road to smaller, more efficient transistor gates in microprocessors ' residual swelling of only a couple of nanometers when the semiconductor is etched.
The discovery points researchers in the direction they'll have to go if they hope to reach the goal of reducing gate size from 45 nanometers to 32 nanometers'a reduction that would result in more powerful and more efficient microprocessors.
With current technologies, a semiconductor wafer is coated with a thin film of photoresist, a polymer-based formulation. A mask is then laid on the wafer, which is then exposed to short-wavelength (193 nm) light. The light changes the solubility of the exposed portions of the photoresist and, when a developer fluid is applied to wash the resist away, the pattern covered by the mask is retained.
It is at this edge between the exposed and unexposed photoresist that NIST researchers found swelling as a result of the developer fluid penetrating several nanometers into the edge of the photoresist.
According to NIST, researchers hope to find a way to alter the interaction to reduce swelling.
Patrick Marshall is a freelance technology writer for GCN.