---
_id: '9959'
abstract:
- lang: eng
text: Ultrasonic heavy wire bonding is a commonly used technology to conduct electrical
devices in power electronics. In order to facilitate powerful solutions combined
with an increased efficiency, involving a material change from aluminum to copper
wire as conductor material takes place in recent years. Due to the material related
properties, copper wire bonding requires significant higher bond processing parameters
such as bond force and ultrasonic power compared to aluminum which can lead to
damages or a failure of the bonded component. Therefore, a profound knowledge
of the processes prevailing during wire bonding is essential to optimize the application
of the copper wires and consequently to achieve the demands on quality and reliability.
The behavior of different natural surface oxides of aluminum and copper are assumed
to be one reason for the deviation in the required bond parameters. Accordingly,
the impact of differently pre-treated substrates surfaces on which the bonding
is applied were investigated in this study. First, all conditions investigated
(as-received, oxidefree, AlOx and the CuOx) were characterized by utilizing scanning
electron microscopy, energy dispersive X-ray spectroscopy, focused ion beam microscopy
and atomic force microscopy. In addition, hardness tests were performed as well
as perthometer measurements. Afterwards, a 500 $\mu$ m copper wire was bonded
on the generated surfaces investigated. In consideration of the roughness, shear
test of various bond times and microscopic images were evaluated. Finally, the
results were compared and discussed. Overall, the current study indicates that
an Al-oxide layer is beneficial for welding process in Cu wire bonding. On the
contrary, the Cu-oxide is detrimental and leads to a delayed welding of the joining
parts. Based on the obtained results, it can be expected that due to an ideal
set of Al-oxide layers, lower optimal bond parameters can used to reach high bond
strength with good reliability properties.
author:
- first_name: Florian
full_name: Eacock, Florian
last_name: Eacock
- first_name: Andreas
full_name: Unger, Andreas
last_name: Unger
- first_name: Paul
full_name: Eichwald, Paul
last_name: Eichwald
- first_name: Olexandr
full_name: Grydin, Olexandr
last_name: Grydin
- first_name: Florian
full_name: Hengsbach, Florian
last_name: Hengsbach
- first_name: Simon
full_name: Althoff, Simon
last_name: Althoff
- first_name: Mirko
full_name: Schaper, Mirko
last_name: Schaper
- first_name: Karsten
full_name: Guth, Karsten
last_name: Guth
citation:
ama: 'Eacock F, Unger A, Eichwald P, et al. Effect of different oxide layers on
the ultrasonic copper wire bond process. In: IEEE 66th Electronic Components
and Technology Conference. ; 2016:2111-2118. doi:10.1109/ECTC.2016.91'
apa: Eacock, F., Unger, A., Eichwald, P., Grydin, O., Hengsbach, F., Althoff, S.,
… Guth, K. (2016). Effect of different oxide layers on the ultrasonic copper wire
bond process. In IEEE 66th Electronic Components and Technology Conference
(pp. 2111–2118). https://doi.org/10.1109/ECTC.2016.91
bibtex: '@inproceedings{Eacock_Unger_Eichwald_Grydin_Hengsbach_Althoff_Schaper_Guth_2016,
title={Effect of different oxide layers on the ultrasonic copper wire bond process},
DOI={10.1109/ECTC.2016.91},
booktitle={IEEE 66th Electronic Components and Technology Conference}, author={Eacock,
Florian and Unger, Andreas and Eichwald, Paul and Grydin, Olexandr and Hengsbach,
Florian and Althoff, Simon and Schaper, Mirko and Guth, Karsten}, year={2016},
pages={2111–2118} }'
chicago: Eacock, Florian, Andreas Unger, Paul Eichwald, Olexandr Grydin, Florian
Hengsbach, Simon Althoff, Mirko Schaper, and Karsten Guth. “Effect of Different
Oxide Layers on the Ultrasonic Copper Wire Bond Process.” In IEEE 66th Electronic
Components and Technology Conference, 2111–18, 2016. https://doi.org/10.1109/ECTC.2016.91.
ieee: F. Eacock et al., “Effect of different oxide layers on the ultrasonic
copper wire bond process,” in IEEE 66th Electronic Components and Technology
Conference, 2016, pp. 2111–2118.
mla: Eacock, Florian, et al. “Effect of Different Oxide Layers on the Ultrasonic
Copper Wire Bond Process.” IEEE 66th Electronic Components and Technology Conference,
2016, pp. 2111–18, doi:10.1109/ECTC.2016.91.
short: 'F. Eacock, A. Unger, P. Eichwald, O. Grydin, F. Hengsbach, S. Althoff, M.
Schaper, K. Guth, in: IEEE 66th Electronic Components and Technology Conference,
2016, pp. 2111–2118.'
date_created: 2019-05-27T09:00:50Z
date_updated: 2019-09-16T10:38:59Z
department:
- _id: '151'
doi: 10.1109/ECTC.2016.91
keyword:
- Ultrasonic copper wire bonding
- Al-oxide
- Cuoxide
- oxide-free
- roughness
- morphology
language:
- iso: eng
page: 2111-2118
publication: IEEE 66th Electronic Components and Technology Conference
quality_controlled: '1'
status: public
title: Effect of different oxide layers on the ultrasonic copper wire bond process
type: conference
user_id: '55222'
year: '2016'
...
---
_id: '34439'
abstract:
- lang: eng
text: A method for the reconstruction of turned shaft surfaces with a (fractal)
Weierstrass–Mandelbrot-function (WMF) is presented. The WMF is modified to allow
to freely choose a phase-shift for every frequency. The reconstruction is based
on distinct profiles in axial and tangential direction and the statistical distribution
of low-wavelength portions of the surface is taken into account by adding t-distributed
random deviations to the surface. The work is validated by reconstructing measured
shaft surfaces with different manufacturing parameters, which shows good accuracy
for periodic surfaces. This method allows for a characterization of surfaces with
a limited number of parameters and can be used to store the characteristics of
measured surfaces with a reduced amount of data compared to a point-cloud surface.
author:
- first_name: Stefan
full_name: Thielen, Stefan
last_name: Thielen
- first_name: Balázs
full_name: Magyar, Balázs
id: '97759'
last_name: Magyar
- first_name: Attila
full_name: Piros, Attila
last_name: Piros
citation:
ama: Thielen S, Magyar B, Piros A. Reconstruction of three-dimensional turned shaft
surfaces with fractal functions. Tribology International. 2016;95:349-357.
doi:https://doi.org/10.1016/j.triboint.2015.11.028
apa: Thielen, S., Magyar, B., & Piros, A. (2016). Reconstruction of three-dimensional
turned shaft surfaces with fractal functions. Tribology International,
95, 349–357. https://doi.org/10.1016/j.triboint.2015.11.028
bibtex: '@article{Thielen_Magyar_Piros_2016, title={Reconstruction of three-dimensional
turned shaft surfaces with fractal functions}, volume={95}, DOI={https://doi.org/10.1016/j.triboint.2015.11.028},
journal={Tribology International}, author={Thielen, Stefan and Magyar, Balázs
and Piros, Attila}, year={2016}, pages={349–357} }'
chicago: 'Thielen, Stefan, Balázs Magyar, and Attila Piros. “Reconstruction of Three-Dimensional
Turned Shaft Surfaces with Fractal Functions.” Tribology International
95 (2016): 349–57. https://doi.org/10.1016/j.triboint.2015.11.028.'
ieee: 'S. Thielen, B. Magyar, and A. Piros, “Reconstruction of three-dimensional
turned shaft surfaces with fractal functions,” Tribology International,
vol. 95, pp. 349–357, 2016, doi: https://doi.org/10.1016/j.triboint.2015.11.028.'
mla: Thielen, Stefan, et al. “Reconstruction of Three-Dimensional Turned Shaft Surfaces
with Fractal Functions.” Tribology International, vol. 95, 2016, pp. 349–57,
doi:https://doi.org/10.1016/j.triboint.2015.11.028.
short: S. Thielen, B. Magyar, A. Piros, Tribology International 95 (2016) 349–357.
date_created: 2022-12-15T09:56:44Z
date_updated: 2026-07-18T13:18:59Z
department:
- _id: '146'
doi: https://doi.org/10.1016/j.triboint.2015.11.028
extern: '1'
intvolume: ' 95'
keyword:
- Roughness
- Structure
- Fractal
- Machining
language:
- iso: eng
page: 349-357
publication: Tribology International
publication_identifier:
issn:
- 0301-679X
quality_controlled: '1'
status: public
title: Reconstruction of three-dimensional turned shaft surfaces with fractal functions
type: journal_article
user_id: '97759'
volume: 95
year: '2016'
...
---
_id: '9772'
abstract:
- lang: eng
text: 'A profound description of friction in wheel--rail contact plays an essential
role for optimization of traction control strategies, as input quantity for railway
simulations in general and for the estimation of wear and rolling contact fatigue.
A multitude of wheel--rail contact models exists, however, traction--creepage
curves obtained from measurements show quantitative and qualitative deviations.
There are several phenomena which influence the traction--creepage characteristics:
Mechanisms resulting from surface roughness, frictional heating or the presence
of interfacial fluids can have a dominating influence on friction. In this paper,
a new wheel--rail contact model, accounting for these influential parameters,
will be presented. The presented model accounts for the interaction of an interfacial
fluid model for combined boundary and mixed lubrication of rough surfaces with
a wheel--rail contact model that additionally accounts for frictional heating.
A quantitative comparison with measurements found in the literature is not conducted,
since the exact conditions of the measurements are mostly unknown and parameters
can easily be adjusted to fit the measurements. Emphasis is placed on the qualitative
behavior of the model with respect to the measurements and good agreement is found.
The dependence of the maximum traction coefficient on rolling velocity, surface
roughness and normal load is studied under dry and water lubricated conditions.'
author:
- first_name: Christoph
full_name: Tomberger, Christoph
last_name: Tomberger
- first_name: Peter
full_name: Dietmaier, Peter
last_name: Dietmaier
- first_name: Walter
full_name: Sextro, Walter
id: '21220'
last_name: Sextro
- first_name: Klaus
full_name: Six, Klaus
last_name: Six
citation:
ama: 'Tomberger C, Dietmaier P, Sextro W, Six K. Friction in wheel--rail contact:
A model comprising interfacial fluids, surface roughness and temperature. Wear.
2011;271:2-12. doi:10.1016/j.wear.2010.10.025'
apa: 'Tomberger, C., Dietmaier, P., Sextro, W., & Six, K. (2011). Friction in
wheel--rail contact: A model comprising interfacial fluids, surface roughness
and temperature. Wear, 271, 2–12. https://doi.org/10.1016/j.wear.2010.10.025'
bibtex: '@article{Tomberger_Dietmaier_Sextro_Six_2011, title={Friction in wheel--rail
contact: A model comprising interfacial fluids, surface roughness and temperature},
volume={271}, DOI={10.1016/j.wear.2010.10.025},
journal={Wear}, author={Tomberger, Christoph and Dietmaier, Peter and Sextro,
Walter and Six, Klaus}, year={2011}, pages={2–12} }'
chicago: 'Tomberger, Christoph, Peter Dietmaier, Walter Sextro, and Klaus Six. “Friction
in Wheel--Rail Contact: A Model Comprising Interfacial Fluids, Surface Roughness
and Temperature.” Wear 271 (2011): 2–12. https://doi.org/10.1016/j.wear.2010.10.025.'
ieee: 'C. Tomberger, P. Dietmaier, W. Sextro, and K. Six, “Friction in wheel--rail
contact: A model comprising interfacial fluids, surface roughness and temperature,”
Wear, vol. 271, pp. 2–12, 2011.'
mla: 'Tomberger, Christoph, et al. “Friction in Wheel--Rail Contact: A Model Comprising
Interfacial Fluids, Surface Roughness and Temperature.” Wear, vol. 271,
2011, pp. 2–12, doi:10.1016/j.wear.2010.10.025.'
short: C. Tomberger, P. Dietmaier, W. Sextro, K. Six, Wear 271 (2011) 2–12.
date_created: 2019-05-13T11:08:32Z
date_updated: 2022-01-06T07:04:19Z
department:
- _id: '151'
doi: 10.1016/j.wear.2010.10.025
intvolume: ' 271'
keyword:
- Wheel--rail contact
- Rolling contact
- Friction
- Interfacial fluid
- Lubrication
- Surface roughness
- Contact temperature
language:
- iso: eng
page: 2 - 12
publication: Wear
publication_identifier:
issn:
- 0043-1648
quality_controlled: '1'
status: public
title: 'Friction in wheel--rail contact: A model comprising interfacial fluids, surface
roughness and temperature'
type: journal_article
user_id: '55222'
volume: 271
year: '2011'
...