As process nodes shrink, the problem of feature variations is increasing. Looking to address the issue, Applied Materials has unveiled the Centris Sym3 etch system. The tool is said to feature an entirely new chamber and to enable what the company calls atomic level precision manufacturing.
Centris Sym3 uses the company's True Symmetry technology, which offers multiple tuning controls that allow processes to be optimised to the atomic level.
One of the key features is the ability to control and remove etch byproducts, which mitigates such problems as line edge roughness, pattern loading and defects.
According to global product manager Amulya Athayde, there are three main challenges: the need for uniformity across the wafer; how to get better dice, with all different features, different pattern densities; and how to deal with variation as designs feature tighter line widths and double patterning.
"In a few years, we'll be down to a couple of atoms variation," he said. "Even now, you can count the atoms. Meanwhile, higher aspect ratios
mean we have to get ions into smaller features and effectively."
The company says it has created features with an aspect ratio of 30:1 on advanced processes. This is achieved by tight control of gas flow, RF plasma and temperature. "The gas has to be distributed evenly and the wafer temperature needs to be uniform," Athayde added. "It'a big challenge getting these factors to work together."
Author
Graham Pitcher
Source: www.newelectronics.co.uk