Band offsets at interfaces of (1 0 0)In@@i@@dx@@Ga@@d1-@@@i@@dx@@As (0 [less-than-or-equals, slant] @@ix@ [less-than-or-equals, slant] 0.53) with Al@@d2@O@@d3@ and HfO@@d2@

• Published in: Microelectronic engineering 2009-09, Vol.86 (7-9), p.1550-1553
• Main Authors: Afanas'ev, V V, Stesmans, A, Brammertz, G, Delabie, A, Sionke, S, O'Mahony, A, Povey, I M, Pemble, M E, O'Connor, E, Hurley, P K, Newcomb, S B
• Format: Article
• Language: English
• ISSN: 0167-9317
• DOI: 10.1016/j.mee.2009.03.003

The electron energy band alignment at interfaces of In@@i@@dx@@Ga@@d1-@@@i@@dx@@As (0 [less-than-or- equals, slant] @@ix@ [less-than-or-equals, slant] 0.53) with atomic-layer deposited insulators Al@@d2@O@@d3@ and HfO@@d2@ is characterized using combined measurements of internal photoemission of electrons and photoconductivity. The measured energy of the In@@i@@dx@@Ga@@d1-@@@i@@dx@@As valence band top is found to be only marginally influenced by the semiconductor composition. This result suggests that the observed bandgap narrowing from 1.42 to 0.75 eV when the In content increases from 0 to 0.53 occurs mostly through downshift of the semiconductor conduction band bottom. Electron states originating from the interfacial oxidation of In@@i@@dx@@Ga@@d1-@@@i@@dx@@As lead to reduction of the electron barrier at the semiconductor/oxide interface.