Deliverables and Services - IHP Microelectronics

9 A n n u A l R e p o R t 2 0 0 9
e r S C H I e N e N e p u B L I K A t I o N e N – p u B L I S H e d p A p e r S
(52) Impact of ti Sputter target denitration
on the Crystallographic orientation of
Single ti Layers and ti / tiN / AlCu Layer
Stacks for different oxides
D. Wolansky, p. Zaumseil
Journal of electronic Materials 38(6), 717
(2009)
the impact of ti sputter target denitridation on the
crystallographic orientation of single ti layers and
ti / tin / Al layer stacks was studied for three different
underlayers: tetraethyl orthosilicate (teoS)-based
chemical vapor deposition (CVD) oxide, silane-based
high-density plasma (HDp) CVD oxide, and thermal
oxide. A clear correlation was found between ti crystal
orientation and ti sputter target conditioning as
well as oxide underlayer. the ti crystal orientation
determines the orientation of the Al in the ti / tin / Al
layer stacks. the most perfect Al(111) orientation
in ti / tin / Al layer stacks was found for a ti layer
sputtered on teoS oxide after a ti target denitridation
of more than 5 s.
(53) epitaxial Growth of Si / SiGe into Cavity
Formed by Selective etching of SiGe
Y. Yamamoto, K. Köpke, G. Weidner, B. tillack
Solid State electronics 53, 824 (2009)
epitaxial growth of Si:C, Si or SiGe in the cavity formed
by selective vapor phase etching of sacrificial SiGe
layer by HCl using a RpCVD system was investigated.
the sacrificial SiGe layer was etched with very high
selectivity. epitaxial Si was deposited into the selectively
etched cavity by non-selective and selective
deposition processes. Weak strain contrast was observed
by teM at the interface where the growthfronts
from top and bottom of the cavity were meeting each
other. no or weak strain contrast was observed in the
Si cap layer at middle to shallow part of the cavity.
By non-selective SiGe growth, the SiGe layer was deposited
on the Si cap layer only. the Si cap layer on
the cavity seems to be bended and pressed down in
the early stage of non-selective SiGe growth. on the
other hand, in the case of selective SiGe growth, the
cavity was filled. Strain contrast was observed by teM
in the Si cap layer on selectively grown SiGe. Bending
of Si cap layer after selective SiGe growth was increased
with increasing Ge concentration, indicating that
tensile strain was generated by SiGe growth in the
cavity.
(54) Minority Carrier Conductive Channel
Formed at a direct Silicon-Bonded
Interfacial Grain Boundary
X. Yu, W. Seifert, o. Vyvenko, M. Kittler
Scripta Materialia 61, 828 (2009)
We have demonstrated that a direct silicon-bonded
interfacial grain boundary (GB) acts as an electrically
conductive channel for minority carriers. this
conductive channel is attributed to the formation of
an inversion layer, resulting in an anomalous bright
electron-beam-induced current contrast of the GB
observed outside the collection diode. the charging
at GB states related to interfacial dislocations and
oxygen precipitates is found to cause a large potential
barrier, which is responsible for the formation of
an inversion layer.
(55) A Complex X-ray Structure Characterization
of Ge thin Film Heterostructures
Integrated on Si(001) by Aspect ratio
trapping and epitaxial Lateral overgrowth
Selective Chemical Vapor deposition
techniques
p. Zaumseil, t. Schroeder, J.-S. park,
J.G. Fiorenza, A. lochtefeld
Journal of Applied physics 106, 093524
(2009)
the development of Ge thin film substrates with low
defect densities is of interest for future microelectronics
as well as photovoltaics. this paper presents
a complex x-ray characterization of Ge heterostructures,
which were integrated on patterned Si(001)
substrates using “aspect ratiotrapping (ARt)” and
“epitaxial lateral overgrowth (elo).” In both cases,
thermal Sio 2 layers were patterned into trenches
with appropriate aspect ratio to confine misfit dislocations.
In the case of ARt Ge thin films grown in
180 nm spaced trenches, the x-ray characterization
reveals that the Ge coalescence process between