IBM makes high-performance plastic ICs.

IBM has made high performance ICs on plastic substrates.

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.

Some attempts have been made to fabricate high-performance CMOS on silicon substrates and then transfer the devices to plastic, but this has been complex and expensive.

IBM has found a way round this., producing 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 60 angstroms.

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.

The devices had gate lengths of <30 nm and gate pitch of 100 nm. The ring oscillators had a stage delay of just 16 ps at 0.9 V, believed to be the best reported performance for a flexible circuit.

A slight degradation of delay for the flexible sample after the layer transfer comes from degradation of p-FET performance due to strain effects.

Flexible circuitry promises a host of innovative biomedical, security, wearable and other products.