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Search Publications by: Joseph J. Kopanski (Assoc)

Displaying 126 - 150 of 256

Surface photovoltage spectroscopy of minority carrier diffusion lengths in undoped and Si-doped GaN epitaxial films

March 24, 2005

Author(s)

Seong-Eun Park, Joseph Kopanski, Youn-Seon Kang, Larry Robins

Undoped and Si-doped GaN epitaxial films have been grown on sapphire substrates by metal-organic chemical vapor deposition. Variable angle spectroscopic ellipsometry (VASE) and surface photovoltage (SPV) spectroscopy were used to determine the minority

Experimental investigation of interface states and photovoltaic effects on the scanning capacitance microscopy measurement for p-n junction dopant profiling

December 20, 2004

Author(s)

Jihui Yang, Joseph Kopanski, A Postula, M Bialkowski

A special scanning capacitance microscopy (SCM) sample preparation method is exploited to make unipolar and p-n junction samples with different interface state densities and an identical oxide thickness. Using these samples, the interface states effect on

Experimental investigation of the dielectric-semiconductor interface with scanning capacitance microscopy

December 20, 2004

Author(s)

Jihui Yang, Joseph Kopanski, A Postula, M Bialkowski

An experimental investigation of how interface states effect scanning capacitance microscopy (SCM) measurements is presented. Different sample polishing procedures were used to make SCM samples that would have different interface state densities, but

Semiconductor Dopant Profiling and Dielectric Characterization with Scanning Capacitance Microscopy

November 30, 2004

Author(s)

Joseph J. Kopanski

Scanning capacitance microscopy (SCM) has been commonly used to image dopant gradients in silicon and other semiconductors. As a mobile, high-resolution (to 10 nm) metal-oxide-semiconductor (MOS) probe, SCM also is a non-destructive, contactless tool with

Influence of Interface Traps and Surface Mobility Degradation on Scanning Capacitance Microscopy Measurement

September 1, 2004

Author(s)

Y. D. Hong, Tong Y. Yeow, W. K. Chim, K. M. Wong, Joseph Kopanski

Scanning Capacitance Microscopy (SCM) is based on metal-oxide-semiconductor (MOS) theory. However, instead of the standard 100 kHz to 1 MHz signal used in conventional MOS capacitance-voltage measurement, SCM uses signal at 915 MHz. At this high frequency

Quantitative Interpretation of Scanning Capcitance Microscope Images as Two-Dimensional Dopant Profiles

March 10, 2004

Author(s)

Joseph Kopanski, Jay F. Marchiando

Scanning capacitance microscopy (SCM) is used as a qualitative analysis tool with multiple applications for failure analysis. SCM can measure the shape of dopant profiles, can ascertain if certain implants have been completed, can verify the conduction

On calculating scanning capacitance microscopy data for a dopant profile in semiconductors

February 1, 2004

Author(s)

Jay F. Marchiando, Joseph Kopanski

While the calculating the dopant profile from SCM data (the inverse problem) can be formulated as a regularized nonlinear least-squares optimization problem, wherein Poisson equations are solved within the quasi-static approximation in each iteration of

PSPICE Analysis of a Scanning Capacitance Microscope Sensor

February 1, 2004

Author(s)

Gyoung H. Buh, Chi Tran, Joseph Kopanski

Towards reproducible SCM Image Interpretation

February 1, 2004

Author(s)

Joseph Kopanski, Jay F. Marchiando, Brian G. Rennex, David S. Simons, R P. Chaudhury

SCM images, and the two-dimensional (2-D) dopant profiles extracted from them, show poor reproducibility from laboratory to laboratory. Major factors contributing to SCM image variability include: poor sample surface and oxide quality, excess carrier

AVS Newsletter Conference Report USJ-2003: The Seventh International Workshop on: Fabrication, Characterization, and Modeling of Ultra-Shallow Doping Profiles in Semiconductors

October 30, 2003

Author(s)

Joseph Kopanski, Erik Collart

USJ-2003 provided an international forum for a broad ranging discussion of the current and future needs for ultra-shallow junctions, new ideas for fabrication of ultra-shallow junctions, recent advancements of analytical characterization techniques, and

Atomic Force Microscope Laser Illumination Effects on a Sample and Its Application for Transient Spectroscopy

September 23, 2003

Author(s)

Gyoung H. Buh, Joseph Kopanski

A scanning capacitance microscope (SCM) is used to monitor the irradiation effect on a sample in a conventional atomic force microscope (AFM). The photo-excitation of carriers in a silicon sample caused by an AFM laser is measured from SCM capacitance

Factors Influencing the Capacitance-voltage Characteristics Measured by the Scanning Capacitance Microscope

August 15, 2003

Author(s)

Gyoung H. Buh, Joseph Kopanski, Jay F. Marchiando, Anthony G. Birdwell, Young Kuk

A scanning capacitance microscope (SCM) can measure the local capacitance-voltage (C-V) characteristics of a metal-oxide-semiconductor structure formed by the SCM probe-tip and the doped semiconductor. When the SCM is operated in the standard configuration

PSPICE Analysis of the Scanning Capacitance Microscope Sensor

April 27, 2003

Author(s)

Gyoung H. Buh, Chi Tran, Joseph Kopanski

A detailed analysis of the capacitance sensor from a scanning capacitance microscope (SCM) is presented. PSPICE circuit simulations are compared with experimental results. The general behavior of the SCM sensor and practical aspects of the sensor-tuning