CEA-Leti announced it has developed two techniques to induce local strain in FD-SOI processes for next-generation FD-SOI circuits that will produce more speed or lower power consumption and improved performance. (For more details, read the press release here.) Targeting the 22/20nm node, the local-strain solutions are dual-strained technologies: compressive SiGe for PFETs and tensile Si for NFETs. In addition to clearing the path to improved performance in FD-SOI technology, they preserve its excellent electrostatic integrity and its in situ performance tunability, due to back biasing.
The two techniques Leti developed can induce local stress as high as 1.6 GPa in the MOSFETs channel. Strained channels enable an increase in the on-state current of CMOS transistors. As a result, chips can deliver more speed at the same power, or reduce consumed power for longer battery life at the same performance. The first technique relies on strain transfer from a relaxed SiGe layer on top of SOI film. The second technique is closer to strain memorization methods and relies on the ability of the BOX to creep under high-temperature annealing.
“These two new techniques broaden the capabilities of Leti’s FD-SOI platform for next-generation devices, and further position the technology to be a vital part of the Internet of Things and electronics products of the future,” said Maud Vinet, head of Leti’s Advanced CMOS Laboratory.