Where academic tradition
meets the exciting future

You are here: TUCS > PUBLICATIONS > Publication Search > Oxidation of the GaAs Semicond...

Oxidation of the GaAs Semiconductor at the Al2O3/GaAs Junction

Marjukka Tuominen, Muhammad Yasir, Jouko Lång, Johnny Dahl, Mikhail Kuzmin, Jaakko Mäkelä, Marko Punkkinen, Pekka Laukkanen, Kalevi Kokko, Karina Schulte, Risto Punkkinen, Ville-Markus Korpijärvi, Ville Polojärvid, Mircea Guinad, Oxidation of the GaAs Semiconductor at the Al2O3/GaAs Junction. Physical Chemistry Chemical Physics 17, 7060–7066, 2015.

http://dx.doi.org/10.1039/C4CP05972G

Abstract:

Atomic-scale understanding and processing of the oxidation of III–V compound–semiconductor surfaces are essential for developing materials for various devices (e.g., transistors, solar cells, and light emitting diodes). The oxidation-induced defect-rich phases at the interfaces of oxide/III–V junctions significantly affect the electrical performance of devices. In this study, a method to control the GaAs oxidation and interfacial defect density at the prototypical Al2O3/GaAs junction grown via atomic layer deposition (ALD) is demonstrated. Namely, pre-oxidation of GaAs(100) with an In-induced c(8 × 2) surface reconstruction, leading to a crystalline c(4 × 2)–O interface oxide before ALD of Al2O3, decreases band-gap defect density at the Al2O3/GaAs interface. Concomitantly, X-ray photoelectron spectroscopy (XPS) from these Al2O3/GaAs interfaces shows that the high oxidation state of Ga (Ga2O3 type) decreases, and the corresponding In2O3 type phase forms when employing the c(4 × 2)–O interface layer. Detailed synchrotron-radiation XPS of the counterpart c(4 × 2)–O oxide of InAs(100) has been utilized to elucidate the atomic structure of the useful c(4 × 2)–O interface layer and its oxidation process. The spectral analysis reveals that three different oxygen sites, five oxidation-induced group-III atomic sites with core-level shifts between −0.2 eV and +1.0 eV, and hardly any oxygen-induced changes at the As sites form during the oxidation. These results, discussed within the current atomic model of the c(4 × 2)–O interface, provide insight into the atomic structures of oxide/III–V interfaces and a way to control the semiconductor oxidation.

BibTeX entry:

@ARTICLE{jTuYaLxDaKuMxPuLaKoScPuKoPoGu15a,
  title = {Oxidation of the GaAs Semiconductor at the Al2O3/GaAs Junction},
  author = {Tuominen, Marjukka and Yasir, Muhammad and Lång, Jouko and Dahl, Johnny and Kuzmin, Mikhail and Mäkelä, Jaakko and Punkkinen, Marko and Laukkanen, Pekka and Kokko, Kalevi and Schulte, Karina and Punkkinen, Risto and Korpijärvi, Ville-Markus and Polojärvid, Ville and Guinad, Mircea},
  journal = {Physical Chemistry Chemical Physics},
  volume = {17},
  pages = {7060–7066},
  year = {2015},
}

Belongs to TUCS Research Unit(s): Embedded Computer and Electronic Systems (ECES)

Publication Forum rating of this publication: level 3

Edit publication