Progler backed up his argument at a lithography seminar, organized by Dai Nippon Screen, saying that he has taken 10 so-called 90-nm devices, looked at the masks and discovered "enormous ground rule differences" among them.

The minimum half-pitch on the 10 logic chips ranged from 110 to 170 nm, Progler said, with none of them having a 90-nm feature anywhere. That drew a chuckle from his audience, as if Grandma had caught a few hands in the cookie jar.

Logic has more single lines, with many more contacts, and a higher metal pitch. Also, logic vendors use etch-back techniques to shrink the actual gate size. "For logic, most companies do an average, taking the contacted metal half-pitch and the poly isolated line, and dividing by two," Gargini said.

Another way of looking at it is that a 90-nm logic device might have a half-pitch of 120 nm and a gate length of 60 nm, producing a device that qualifies-for marketing purposes-as a 90-nm chip. Gargini said scaling is determined by a company's return on investment (ROI) and competitive pressures. "If your ROI allows you to scale as fast as possible, why not go as fast as you can?" he asked.

I'm all for fast horses; it makes the semiconductor industry race more interesting. But how about that 170-nm half-pitch that is being pawned off as a 90-nm chip?

David Lammers covers SoC process equipment. Contact him at dlammers@cmp.com.