Effects of nano-pattern size on the property of InAs site-controlled quantum dots

✍ Scribed by Chien-Chia Cheng; K. Meneou; K.Y. Cheng

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 417 KB
• Volume: 323
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.10.119

✦ Synopsis

Soft photocurable nanoimprint lithography has been used to pattern (1 0 0) GaAs substrate into periodic nucleation sites for the growth of InAs site-controlled quantum dots (SCQDs). The pattern is a twodimension square array of nanopores with size ranging from 60 to 110 nm, which is tunable by adjusting imprint process parameters. Under the same growth conditions, we demonstrated single-dot occupancy on samples with smaller nanopore size while multiple dots are observed within each nanopore on samples with larger nanopore size. Moreover, room temperature photoluminescence from SCQDs grown on patterned substrates with smaller nanopores reveals a 20% reduction in linewidth and doubled peak intensity relative to those grown on patterned substrates with larger nanopores. These superior characteristics indicate a more uniform SCQD formation and a favourable SCQD growth in patterned samples with smaller nanopores sizes ( $ 60 nm).