Strain-Enhanced Tunnel Diode Technology

"We intend to increase by an order of magnitude, the current density of silicon-based tunnel diodes. This increase directly relates to a corresponding increase in performance (speed). Apart from being the fastest of all microelectronic devices, tunneldiodes (TDs) have negative differential resistance, which gives them unusual circuit qualities. When attached to integrated circuits they improve the circuit parameters (by two or three times). They enable fewer transistors to be used, power consumption islowered, circuit speed is increased, and the layout area is reduced. TDs are being developed for use in high-speed radar & communications, signal processing, data conversion and memory. The integration of tunnel diodes into silicon ICs is therefore highlydesirable. Si tunnel diodes have a current density of up to ~10 kA/cm2, we can double this figure by low-level straining (0.05%). We believe further optimization up to 1% strain would yield figures for Si-based TDs comparable to III-V TD devices (100kA/cm2). Integration of high current density (100kA/cm2), low capacitance, tunnel diodes incorporated into ICs has great benefits in e.g. lowering power consumption by a factor of 2, while increasing overall circuit speed by a factor of 2 and reducinglayout area by a factor of 3."