Flexible CMOS with SOI
Flexible circuitry promises a host of innovative biomedical, security, wearable, and other products. To date, flexible circuits have offered only limited performance because plastic substrates aren’t compatible with the high temperatures/harsh processes needed to make high-performance CMOS devices. Fabricating high-performance CMOS on silicon substrates, and then transferring the devices to plastic, has shown to be complex and expensive.
At IEDM, for the first time, a way around this will be unveiled: IBM researchers will demonstrate high-performance state-of-the-art CMOS circuits, including SRAM memory and ring oscillators, on a flexible plastic substrate. The extremely thin silicon on insulator (ETSOI) devices had a body thickness of just 60Å. IBM built them on silicon and then used a simple, low-cost room-temperature process called "controlled spalling," which essentially flakes off the Si substrate. Then they transferred them to flexible plastic tape. (#5.1: "Advanced Flexible CMOS Integrated Circuits on Plastic Enabled by Controlled Spalling Technology")
XTEM of a Ge-channel FET with SiGe source/drain.