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Search Publications by: Yaw S. Obeng (Fed)

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Displaying 126 - 150 of 172

Development of a Methodology to Determine Risk of Counterfeit Use

June 5, 2013
Author(s)
Mark Schaffer, Yaw S. Obeng
Counterfeit components have become a multi-million dollar, yet undesirable, part of the electronics industry. The profitability of the counterfeit industry rests in large part on its ability to recognize supply constraints and quickly respond, effectively

Accelerated Stress Test Assessment of Through-Silicon Vias Using RF Signals

June 1, 2013
Author(s)
Chukwudi A. Okoro, Pavel Kabos, Jan Obrzut, Klaus Hummler, Yaw S. Obeng
In this work, radio frequency (RF) signal is demonstrated as an effective metrology tool for the assessment of the effect of thermal cycling on the reliability of through-silicon via (TSV) stacked dies. It was found that RF signal integrity of TSV daisy

Use of RF-Based Technique as a Metrology Tool for TSV Reliability Analysis

May 28, 2013
Author(s)
Chukwudi A. Okoro, Yaw S. Obeng, Jan Obrzut, Pavel Kabos, Klaus Hummler
In this work, we used radio frequency (RF) based measurement technique is used as a prognostic tool for the assessment of the effect of thermal cycling on the reliability of through-silicon via (TSV) stacked dies. It was found that RF signal integrity in

X-Ray Micro-Beam Diffraction Determination of Full Stress Tensors in Cu TSVs

May 28, 2013
Author(s)
Chukwudi A. Okoro, Lyle E. Levine, Oleg A. Kirillov, Yaw S. Obeng, Ruqing Xu, Jonathan Z. Tischler, Wenjun Liu, Klaus Hummler
We report the first non-destructive, depth resolved determination of the full stress tensor in Cu through-silicon vias (TSVs), using synchrotron based micro-beam X-ray diffraction. Two adjacent Cu TSVs were studied; one deliberately capped with SiO2, the

Measurement Science for "More-Than-Moore" Technology Reliability Assessments

October 12, 2012
Author(s)
Chukwudi A. Okoro, Jungjoon Ahn, Meagan V. Kelso, Pavel Kabos, Joseph Kopanski, Yaw S. Obeng
In this paper, we will present an overview of metrology issues and some of the techniques currently under development in our group at NIST, aimed at understanding some of the potential performance limiting issues in such highly integrated systems. We will

Metrology for Nanosystems and Nanoelectronics Reliability Assessments

August 20, 2012
Author(s)
Yaw S. Obeng, Chukwudi A. Okoro, Joseph J. Kopanski
The traditional models and techniques for studying reliability in integrated circuits may not be appropriate for nanoelectronics and nanosystems. In this paper, we present an overview of a number of materials and metrology techniques currently under

A Case Study on the Impact of Local Material Chemistry on the Mechanical Reliability of Packaged Integrated Circuits: Correlation of the Packaging Fallout to the Chemistry of Passivation Dielectrics in an Al-Cu System

March 19, 2012
Author(s)
Chukwudi A. Okoro, Yaw S. Obeng
In this paper, we use a variety of analytical techniques to examine the impact of local chemistry, and the mechanical properties, of the encapsulation dielectric films on the post-packaging device rejection rate of integrated circuit devices. A strong

Towards clean and crackless transfer of graphene

January 2, 2012
Author(s)
Xuelei X. Liang, Brent A. Sperling, Irene G. Calizo, Guangjun Cheng, Christina Hacker, Qin Zhang, Yaw S. Obeng, Kai Yan, Hailin Peng, Qiliang Li, Xiaoxiao Zhu, Hui Yuan, Angela R. Hight Walker, Zhongfan Liu, Lianmao Peng, Curt A. Richter
We present the results of a thorough study of wet chemical methods for transferring chemical vapor deposition grown graphene from the metal growth substrate to a device compatible substrate. Based on these results, we have developed a "modified RCA clean"

The Case for Innovations in Photovoltaics: the Nonmaterial Edge

January 26, 2011
Author(s)
Yaw S. Obeng, Kathleen C. Richardson
The limitations of current thin film and the gaps to cost efficient photovoltaic (PV) cells will be discussed in the presentation. This discussion will suggest ways to improve PV cell performance through the use of reduced dimension materials (e.g