Deliverables and Services - IHP Microelectronics

92 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
(45) Combined XBIC / µ-XrF / µ-XAS / dLtS
Investigation of Chemical Character and
electrical properties of Cu and Ni
precipitates in Silicon
M. trushin, o. Vyvenko, W. Seifert, M. Kittler,
I. Zizak, A. erko, M. Seibt, C. Rudolf
physica Status Solidi C 6, 1868 (2009)
Combination of DltS method and synchrotron-based
analytical microprobe techniques was used to study
the precipitation of Cu and ni atoms at two kinds of
structural defects in silicon lattice: dislocation network
created by direct wafer bonding and oxygeninduced
microdefects. Results of our measurements
revealed the difference in the preferred precipitation
places: ni particles in form of niSi 2 were found only at
the dislocation network, while Cu particles in form of
Cu 3 Si were found both at the dislocation network and
at the oxygen-induced microdefects. DltS measurements
showed ni acceptor levels in ni contaminated
sample and a broad band related to Cu precipitates in
Cu contaminated one. In case of simultaneous Cu and
ni contamination niSi 2 and Cu 3 Si precipitates were
found definitely at the same places indicating therefore
that the metals interact during precipitation.
DltS showed the superposition of spectra for only ni
and for only Cu contaminated samples.
(46) Iron-oxygen Interaction in Silicon: A
Combined XBIC / XrF-eBIC-dLtS Study of
precipitation and Complex Building
M. trushin, o. Vyvenko, W. Seifert, G. Jia,
M. Kittler
physica B: Condensed Matter 404, 4645
(2009)
Iron–oxygen interaction in the Czochralski-grown silicon
(CZ-Si) giving rise to their final precipitated state
was investigated by means of a combination of electrical
and element-sensitive techniques. the samples
studied were intentionally contaminated with iron at
1150 °C and then they were annealed at temperatures
of 850 and 950 °C to stimulate precipitate formation.
Fe-related defect levels in silicon band gap and spatial
distributions of iron-related precipitates were monitored
after each annealing step. It was found that
FeB-pairs being the dominant defects in as-contaminated
sample transformed completely to the stable
Feo-related complexes that served as precursors for
further iron–oxygen co-precipitation.
(47) pulse-Induced Low-power resistive
Switching in Hfo 2 Metal-Insulator-Metal
diodes for Nonvolatile Memory Applications
Ch. Walczyk, Ch. Wenger, R. Sohal,
M. lukosius, A. Fox, J. Dabrowski, D. Wolansky,
B. tillack, H.-J. Müssig, t. Schroeder
Journal of Applied physics 105, 114103
(2009)
the conduction process as well as the unipolar resistive
switching behavior of Au / Hfo 2 / tin metal-insulator-metal
structures were investigated for future
nonvolatile memory applications. With current-voltage
measurements performed at different temperatures
(200 – 400 K), the poole–Frenkel effect as
conduction process was identified. In particular, we
extracted a trap energy level at Φ t =0.35±0.05 eV below
the Hfo 2 conduction band to which a microscopic
origin is tentatively assigned. From current-voltage
measurements of Au / Hfo 2 / tin structures, low-power
(as low as 120 µW) resistive switching was observed.
the required forming process is shown to be an
energy-induced phenomenon. the characteristics
include electric pulse-induced resistive switching
by applying pulses up to 100 µs and a retention time
upon continuous nondestructive readout of more
than 10 4 s.
(48) Band Alignment and electron traps in y 2 o 3
Layers deposited on (100) Si
W.-Ch. Wang, M. Badylevich, V.V. Afanas‘jev,
A. Stesmans, S. Van elshocht, M. lukosius,
Ch. Walczyk, Ch. Wenger
Applied physics letters 95, 132903 (2009)
Y 2 o 3 films deposited by atomic vapor deposition on
(100)Si with a 2 or 5 nm thick pregrown thermal Sio 2
are investigated as possible charge trapping layers.
Analysis of these structures using spectroscopic ellipsometry,
photoconductivity, and internal photoemission
reveals that Y 2 o 3 has a 5.6 eV wide optical