Regensburg 2004 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HL: Halbleiterphysik

HL 31: Grenz- und Oberfl
ächen

HL 31.2: Vortrag

Mittwoch, 10. März 2004, 17:00–17:15, H14

DLTS investigation of UHV bonded Si interfaces — •Alin Mihai Fecioru, Stephan Senz, Roland Scholz, and Ulrich Goesele — Max-Planck-Institut für Mikrostrukturphysik, 06120 Halle

Si-Si interfaces were obtained by ultrahigh vacuum (UHV) wafer bonding. The electrical properties were characterized by deep level transient spectroscopy (DLTS) measurements correlated with temperature dependent current-voltage (I-V) measurements.

For a p-p interface a high density of defects was observed, indicated by a peak in the DLTS spectrum correlated with a thermally active potential barrier. Typical values of activation energy corresponding to the middle of the bandgap are obtained.

For p-n samples the DLTS spectra feature a peak whose corresponding activation energy is depending on the relative doping of the sample: very close to the middle of the bandgap for weakly doped and p+n samples and of about 0.26 eV for n++p samples. Further study by Laplace DLTS shows a continuos distribution in energy for non-annealed samples, and fine structure for annealed samples.

Room temperature bonded samples are compared with samples bonded at 250 ^∘C yielding a decrease of the defect density at the interface. Additionally, TEM investigations were showing a more regular dislocation network for the high temperature bonded samples.