Nanostructures for nanoelectronics: No potential for room temperature applications?

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 (<10ns) and good endurance (>1015>1015 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 Al0.9Ga0.1AsAl0.9Ga0.1As 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 10-1210-12. Their peak differential efficiency decreases only from 0.7 W/A at 25∘C to 0.6 W/A at 85∘C.