Nanostructures for nanoelectronics: No potential for room temperature applications?

Abstract

A novel type of memory based on self-organized quantum dots (QDs) is proposed in the first part of this article. The future QD-Flash will merge the advantages of the classical dynamic random access memory (DRAM) and the Flash to a non-volatile memory with fast access times ( < 10 ns ) and good endurance ( > 10 15 write/erase cycles). In a first step towards a QD-Flash, we demonstrate here a hole retention time of 1.6 s at room temperature in InAs/GaAs QDs with an additional Al 0.9 Ga 0.1 As barrier. This value is already more than three orders of magnitude longer than the refresh time in a DRAM memory. A retention time of more than 10 years is predicted for (InGa)Sb QDs in an AlAs matrix. In the second part, we demonstrate vertical-cavity surface-emitting lasers based on the submonolayer deposition growth mode of InAs, operating error free at 20 Gbit/s between 25 and 85 ∘ C with a bit-error-rate below 10 - 12 . Their peak differential efficiency decreases only from 0.7 W/A at 25 ∘ C to 0.6 W/A at 85 ∘ C .