We describe the growth and properties of (In0.5 Al0.5) 1-x Mnx As and (In0.5 Ga0.5) 1-x Mnx As epilayers and superlattices. We find that the structural quality of the epilayers is similar to that of the more extensively studied In1-x Mnx As and Ga1-x Mnx As magnetic semiconductors and that we can incorporate significantly larger amounts of Mn (∼12%) without phase segregation. Magnetization measurements indicate that the Curie temperatures of (In0.5 Ga0.5) 1-x Mnx As and (In0.5 Al0.5) 1-x Mnx As (x∼0.11) epilayers are 95 and 25 K, respectively. The Curie temperature of the (In0.5 Ga0.5) 1-x Mnx As (In0.5 Al0.5) 1-x Mnx As superlattices decreases with the increase of the Al (Al+Ga) ratio. We attribute this to a decreased overlap between the impurity band and the valence band because of an enhanced Mn acceptor activation energy.
|Original language||English (US)|
|Number of pages||4|
|Journal||Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures|
|State||Published - 2005|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Electrical and Electronic Engineering