A novel nonvolatile memory based on self-organized quantum dots

✍ Scribed by A. Marent; M. Geller; D. Bimberg

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 446 KB
• Volume: 40
• Category: Article
• ISSN: 0026-2692
• DOI: 10.1016/j.mejo.2008.06.056

✦ Synopsis

A novel type of memory based on self-organized quantum dots (QDs) is presented, which merges the advantages of the most important semiconductor memories, the dynamic random access memory (DRAM) and the Flash. A nonvolatile memory with fast access times ðo10 nsÞ and good endurance (410 15 write/erase cycles) as an ultimate solution seems possible. A storage time of 1.6 s at 300 K in InAs=GaAs QDs with an additional Al 0:9 Ga 0:1 As barrier is demonstrated and a retention time of 10 6 years is predicted for GaSb QDs in an AlAs matrix. A minimum write time of 6 ns is obtained for InAs/GaAs QDs. This value is already in the order of the access time of a DRAM cell and at the moment limited by the RC low pass of the device. An erase time of milliseconds is shown in first measurements on GaSb=GaAs QDs at 100 K. Faster write/erase times below 1 ns even at room temperature are expected for improved device structures.