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Search Publications by Joseph J. Kopanski

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Displaying 1 - 25 of 125

Electric Field Gradient Reference Material for Scanning Probe Microscopy

April 1, 2019
Joseph J. Kopanski, Lin You
Any eSPM measurement of a spatially varying electric field at the surface of a sample has a large uncertainty due to the unknown details of the tip shape near the surface. We have designed an electric field gradient reference sample to provide an

Probe assisted localized doping of aluminum into silicon substrates

February 20, 2019
Jungjoon Ahn, Santiago D. Solares, Lin You, Hanaul Noh, Joseph J. Kopanski, Yaw S. Obeng
In this paper, we demonstrate AFM probe assisted deterministic doping (PADD) of Al into an n- type Si (100) wafer, to generate nanoscale counter-doped junctions with a few nanometers depth from Si surface. The local electrical potential changes resulting

Method for Determining the Electrical Shape of a Scanning Probe Microscope Tip

April 2, 2018
Joseph J. Kopanski, Malcolm Regan, Lin You
Knowledge of the actual electrical tip shape can be used to better understand electric field gradients measured with eSPMs and to determine the suitability of various types of conducting SPM tips for electrical measurements. For co-axially shielded tips

Remote Bias Induced Electrostatic Force Microscopy for Subsurface Imaging

March 5, 2018
Joseph J. Kopanski, Lin You, Yaw S. Obeng
Contrast in electrostatic force microscopy (EFM) depends on the electrostatic force between the tip and sample. In the related technique, scanning Kelvin force microscopy (SKFM), contrast arises from the force due to the capacitance gradient with tip-to

Rapid and Accurate C-V Measurements

October 1, 2016
Jihong Kim, Pragya R. Shrestha, Jason P. Campbell, Jason T. Ryan, David M. Nminibapiel, Joseph J. Kopanski, Kin P. Cheung
We report a new technique for the rapid measurement of full capacitance-voltage (C-V) characteristic curves. The displacement current from a 100 MHz applied sine-wave, which swings from accumulation to strong inversion, is digitized directly using an

Characterization of Buried Interfaces with Scanning Probe Microscopes

May 19, 2016
Joseph J. Kopanski, Lin You, Jungjoon Ahn, Yaw S. Obeng
Scanning probe microscopes (SPMs) have some capability to image sub-surface structure, including the details of buried interfaces. This paper describes the theoretical and practical basis for obtaining information about shallow buried interfaces

Dielectric Spectroscopic Detection of Early Failures in 3-D Integrated Circuits

October 11, 2015
Yaw S. Obeng, Chukwudi A. Okoro, Jungjoon Ahn, Lin You, Joseph J. Kopanski
The commercial introduction of three dimensional integrated circuits (3D-ICs) has been hindered by reliability challenges, such as stress related failures, resistivity changes, and unexplained early failures. In this paper, we discuss a new RF-based

Nanoelectronic Structural Information with Scanning Probe Microscopes

June 14, 2015
Joseph J. Kopanski, Lin You, Jungjoon Ahn, Yaw S. Obeng
Scanning probe microscope (SPM) based methods to obtain subsurface structural information about nano-structured materials are described. A test structure chip containing structures to produce various surface electric field gradients, spatially varying

Electromagnetic Field Test Structure Chip for Back End of the Line Metrology

March 23, 2015
Lin You, Jungjoon Ahn, Emily Hitz, Jonathon Michelson, Yaw S. Obeng, Joseph J. Kopanski
A test chip to produce known and controllable gradients of surface potential and magnetic field at the chip surface and suitable for imaging with various types of scanning probe microscopes is presented. The purpose of the test chip is to evaluate various

Influence of Metal?MoS2 Interface on MoS2 Transistor Performance: Comparison of Ag and Ti Contacts

December 16, 2014
Hui H. Yuan, Guangjun Cheng, Lin You, Haitao Li, Hao Zhu, Wei Li, Joseph J. Kopanski, Yaw S. Obeng, Angela R. Hight Walker, David J. Gundlach, Curt A. Richter, D. E. Ioannou, Qiliang Li
In this work, we present a study of enhancing MoS2 transistor performance by using proper metal contact. We found that the on-state current of MoS2 field-effect transistors with 30 nm Au/ 30 nm Ag contacts is enhanced more than 60 times and the

Broad-Band Microwave-Based Metrology Platform Development: Demonstration of In-Situ Failure Mode Diagnostic Capabilities for Integrated Circuit Reliability Analyses

November 7, 2014
Lin You, Chukwudi A. Okoro, Jungjoon Ahn, Joseph J. Kopanski, Yaw S. Obeng, Rhonda R. Franklin
In this paper, we discuss the use of broadband high frequency electromagnetic waves (RF) to non- destructively identify, classify and characterize performance-limiting defects in emerging nanoelectronic devices. As an illustration, the impact of thermal

Scanning Probe Microscopes for Subsurface Imaging

May 11, 2014
Joseph J. Kopanski, Lin You, Jungjoon Ahn, Emily Hitz, Yaw S. Obeng
Scanning probe microscopes (SPMs) have some ability to image sub-surface structures. This paper describes the theoretical and practical basis for imaging metal lines buried beneath insulating layers and for imaging insulating regions or voids within metal

Charge-Based Capacitance Measurements Circuits for Interface With Atomic Force Microscope Probes

March 25, 2013
Joseph J. Kopanski, Muhammad Y. Afridi, Chong Jiang, Michael Lorek, Timothy Kohler, Curt A. Richter
The charge based capacitance measurement (CBCM) technique is highly sensitive to small capacitances and capable integration of onto an AFM tip, thereby reducing stray and wire capacitance to the bare minimum. The CBCM technique has previous been applied to

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

October 12, 2012
Chukwudi A. Okoro, Jungjoon Ahn, Meagan V. Kelso, Pavel Kabos, Joseph J. 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
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

Calibration Techniques for Scanning Microwave Microscopy

July 1, 2012
Thomas M. Wallis, Atif A. Imtiaz, Alexandra Curtin, Pavel Kabos, H. P. Huber, Joseph J. Kopanski, F. Kienberger
Two techniques are described for calibrating a scanning microwave microscope (SMM). The first technique enables spatially-resolved absolute capacitance measurements on the attofarad-to-femtofarad scale. The second technique enables profiling or dopant