Intel says 45nm "Penryn" quad-core chip samples produced@ 2006/12/18
At the tiny scale of 45-nanometer transistors and wires, a single speck of dust on a 300-millimeter silicon wafer can destroy an entire processor. Lower manufacturing yields cut into a company's profit margin, reducing the number of functional chips they can sell from each wafer.
"As an industry, we're running out of gas at 45nm geometry," said Nick Kepler, vice president of logic technology development for AMD. "We've been unable to scale the size as much as we used to because of leakage. We're still putting transistors closer together but not shrinking the gates. So geometry shrinks can hurt you now, which they haven't in the past."