LONDON – Globalfoundries Inc. is evaluating a third manufacturing option to follow conventional bulk planar CMOS: super-steep retrograde well (SSRW) technology that creates a ground plane under a transistor using a doping technique.
The technology appears to be very similar to that developed by SuVolta Inc. (Los Gatos, Calif.) although Globalfoundries (Milpitas, Calif.) has declined to say whether it is working with or in negotiations with SuVolta.
If adopted, the SSRW process would likely be in addition to previously announced 14XM 14-nm FinFET process due in 2014 and its licensing of 28-nm and 20/14-nm fully-depeleted silicon on insulator (FD-SOI) manufacturing process technology from STMicroelectronics. However, it could potentially compete with both processes for design wins.
The possibility that Globalfoundries could pursue all three options underscores the challenges facing conventional bulk planar CMOS.
Globalfoundries CEO Ajit Manocha referred to SSWR in a presentation during the International Electron Devices Meeting (IEDM) in San Francisco earlier this month. Manocha said SSWR – alongside FinFETs and FDSOI – represents a manufacturing option for fully depleted transistor architectures and that fully depleted transistors offer superior low voltage and electrostatic performance along with scalability.
When SuVolta introduced its deeply depleted channel (DDC) PowerShrink transistor technology it pitched it as an alternative to FinFET and FDSOI processes.
Schematic cross-section of Deeply Depleted Channel PowerShrink transistor technology. (Source: SuVolta)