Spectroscopic XPEEM of highly conductive SI-doped GaN wires

Olivier Renault (1) , J. Morin (1) , Pierre Tchoulfian (2) , Chevalier Nicolas (1) , V. Feyer (3) , Julien Pernot (2, 4) , Claus Michael Schneider (5)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 NEEL - SC2G - Semi-conducteurs à large bande interdite
3 Peter Grünberg Institut
4 IUF - Institut universitaire de France
5 PGI-6 - Forschungszentrum Jülich Peter Grünberg Institute

Using soft X-ray photoelectron emission microscopy (XPEEM), complemented by scanning Auger microscopy (SAM) and scanning capacitance microscopy, we have quantitatively studied the incorporation of silicon and band bending at the surface (m-facet) of an individual, highly conductive Si-doped GaN micro-wires (Tchoulfian et al., Applied Physics Letters 102 (12), 2013). Electrically active n-dopants Si atoms in Ga interstitial sites are detected as nitride bonding states in the high-resolution Si2p core level spectra, and represent only a small fraction (<10%) of the overall Si surface concentration measured by SAM. The derived carrier concentration of 2×1021 at cm−3 is in reasonable agreement with electrical measurements. A consistent surface band bending of ~1 eV is directly evidenced by surface photo-voltage measurements. Such an approach combining different surface-sensitive microscopies is of interest for studying other heavily doped semiconducting wires.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Olivier Renault, J. Morin, Pierre Tchoulfian, Chevalier Nicolas, V. Feyer, et al.. Spectroscopic XPEEM of highly conductive SI-doped GaN wires. Ultramicroscopy, 2015, LEEM-PEEM 9, 159 (3), pp.476-481. ⟨10.1016/j.ultramic.2015.05.007⟩. ⟨hal-01364092⟩