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Search Publications by: Nicholas Barbosa (Fed)

Displaying 26 - 45 of 45

From the bottom up  measuring bulk mechanical properties via microtechnology

June 10, 2010

Author(s)

Nicholas Barbosa, Sudook A. Kim, David T. Read

The micromechanics community has developed a large set of tools for measuring the properties of micro- and nano-scaled materials. These new tools have been successfully applied to a range of materials, most often in thin-film form, to determine the

Spatially and Temporally Resolved Thermal Imaging of Cyclically Heated Interconnects by Use of Scanning Thermal Microscopy

January 1, 2008

Author(s)

Nicholas Barbosa, Andrew J. Slifka

A scanning thermal microscope (SThM) was used to investigate the spatial and temporal distribution of temperature in electrical interconnect structures designed for measuring the mechanical properties of thin films. Knowledge of the thermal behavior of the

Constraint Effect in Deformation of Copper Interconnect Lines Subjected to Cyclic Joule Heating

November 26, 2007

Author(s)

David T. Read, Roy H. Geiss, Nicholas Barbosa

Using finite element analysis, we calculate the temperature range and the resulting cyclic Von Mises strain resulting from Joule heating, generated by the application of alternating current, applied to specimens representative of commercial copper

Evaluation of Thin Film Mechanical Properties by Means of Electrical Test Methods

September 30, 2007

Author(s)

Nicholas Barbosa, Robert Keller, David T. Read, Richard P. Vinci

The ability to measure the mechanical properties of thin films and small scale structures is essential in designing reliable components at the micro- and nano-scales. It is known that the mechanical properties of thin film materials deviate from relations

An Electrical Method for Measuring Fatigue and Tensile Properties of Thin Films on Substrates

August 15, 2007

Author(s)

Robert Keller, Nicholas Barbosa, Roy H. Geiss, David T. Read

A novel approach for measuring thermal fatigue lifetime and ultimate strength of patterned thin films on substrates is presented. The method is based on controlled application of cyclic joule heating by means of low-frequency, high-density alternating

Interaction of environmental conditions: Role in the reliability of active implantable devices

June 7, 2007

Author(s)

Elizabeth S. Drexler, Andrew J. Slifka, Nicholas Barbosa, John W. Drexler

Present techniques for assessing the reliability of active implantable medical devices (AIMDs) rely on testing one or two environmental conditions at a time. But the interaction of these environmental conditions may have a greater impact on reliability

Results of a Nanoindentation Round Robin on Thin Film Copper on Silicon

January 1, 2007

Author(s)

David T. Read, Robert Keller, Nicholas Barbosa, Roy H. Geiss

Nanoindentation is used in a variety of fields to measure material hardness and elastic modulus. This test technique is especially attractive for thin films because of the difficulty of conducting tensile or other conventional mechanical characterization

Strain-Induced Grain Growth during Rapid Thermal Cycling of Aluminum Interconnects

January 1, 2007

Author(s)

Robert Keller, Roy H. Geiss, Nicholas Barbosa, Andrew Slifka, David T. Read

We demonstrate by use of automated electron backscatter diffraction (EBSD) the rapid growth of grains in non-passivated, sputtered Al-1Si interconnects during 200 Hz thermal cycling induced by alternating electric current. Mean grain diameters were

Mapping substrate/film adhesion with contact-resonance-frequency AFM

July 12, 2006

Author(s)

Donna C. Hurley, Malgorzata Kopycinska-Mueller, Eric Langlois, Tony B. Kos, Nicholas Barbosa

We demonstrate contact-resonance-frequency atomic force microscopy (AFM) techniques to nondestructively image variations in adhesion at a substrate/film interface. Contact-resonance-frequency imaging is a dynamic AFM technique to measure the contact

Electrical Methods for Mechanical Characterization of Interconnect Thin Films

September 1, 2005

Author(s)

Robert Keller, Cynthia A. Volkert, Roy H. Geiss, Andrew Slifka, David T. Read, Nicholas Barbosa, Reiner Monig

We describe the use of electrical methods for evaluating mechanical reliability and properties of patterned copper and aluminum interconnects on silicon substrates. The approach makes use of controlled Joule heating, which causes thermal strains in the