Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: John A. Kramar (Fed)

Displaying 76 - 100 of 134

Progress Towards SI Traceable Force Metrology for Nanomechanics

January 1, 2004

Author(s)

David B. Newell, Eric P. Whitenton, John A. Kramar, Jon R. Pratt, Douglas T. Smith

This paper is based, in its entirety, on NIST-approved publications: Calibration of Piezoresistive Cantilever Force Sensors Using the NIST Electrostatic Force Balance, The NIST Electrostatic Force Balance Experiment, The NIST Microforce Realization and

Progress Towards Systeme International d'Unites Traceable Force Metrology for Nanomechanics

January 1, 2004

Author(s)

Jon R. Pratt, Douglas T. Smith, David B. Newell, John A. Kramar, Eric P. Whitenton

Recent experiments with the National Institute of Standards and Technology (NIST) Electrostatic Force Balance (EFB) have achieved agreement between an electrostatic force and a gravitational force of 10^(-5) N to within a few hundred pN/¿N. This result

Calibration of Piezoresistive Cantilever Force Sensors Using the NIST Electrostatic Force Balance

November 16, 2003

Author(s)

Jon R. Pratt, David B. Newell, John A. Kramar, Eric P. Whitenton

The characterization of material properties and mechanical performance of micro-electromechanical devices often hinges on the accurate measurement of small forces. Calibrated load cells of appropriate size and range are used, but are often not calibrated

Dependence of Morphology on Miscut Angle for Si(111) Etched in NH(4)F

May 1, 2003

Author(s)

S Gonda, Joseph Fu, John A. Kramar, Richard M. Silver, Hui Zhou

Using scanning probe microscopy, we have examined the surfaces produced by etching several different vicinal Si(111) samples in NH(4)F aqueous solution. In agreement with others, we found that deoxygenation of the etchant generally reduces the number of

Dependency of Morphology on Miscut Angle for Si(111) Etched in NH 4 F

May 1, 2003

Author(s)

Joseph Fu, Hui Zhou, John A. Kramar, Richard M. Silver, S Gonda

Using scanning probe microscopy, we have examined the surfaces produced by etching several different vicinal Si(111) samples in NH 4F aqueous solution. In agreement with others, we found that deoxygenation of the etchant generally reduces the number of

The NIST Microforce Realization and Measurement Project

April 1, 2003

Author(s)

David B. Newell, Edwin R. Williams, John A. Kramar, Jon R. Pratt, Douglas T. Smith

The National Institute of Standards and Technology (NIST) has launched a five-year Micro-force Realization and Measurement project focusing on the development of an instrument and laboratory capable of realizing and measuring the SI unit of force below

Microforce and Instrumented Indentation Research at the National Institute of Standards and Technology, Gaithersburg, MD

January 1, 2003

Author(s)

Jon R. Pratt, David B. Newell, John A. Kramar, Douglas T. Smith

This paper provides an overview of recent efforts at the National Institute of Standards and TEchnology to develop metrology and standards to support general users of instrumented indentation and scan-probe devices. Research directed towards a primary

Probe-Force Calibration Experiments Using the NIST Electrostatic Force Balance

January 1, 2003

Author(s)

Jon R. Pratt, David B. Newell, John A. Kramar, J Mulholland, Eric P. Whitenton

The sensitivity of a piezoresistive cantilever force sensor has been determined by probing the weighing pan of the NIST prototype electrostatic force balance. In this experiment, micronewton contact forces between a force probe and the balance''s weighing

The NIST Microforce Realization and Measurement Project

June 1, 2002

Author(s)

David B. Newell, Jon R. Pratt, John A. Kramar, Douglas T. Smith, Edwin R. Williams

The National Institute of Standards and Technology (NIST) has launched a five-year Microforce Realization and Measurement project focusing on the development of an instrument and laboratory capable of realizing and measuring the SI unit of force below

The NIST Microforce Realization and Measurement Project

June 1, 2002

Author(s)

David B. Newell, Jon R. Pratt, John A. Kramar, Douglas T. Smith, Edwin R. Williams

A Flexure Balance With Adjustable Restoring Torque for Nanonewton Force Measurement

January 1, 2002

Author(s)

Jon R. Pratt, David B. Newell, John A. Kramar

The NIST electrostatic force balance compares mechanical probe forces to an SI realization of force derived from measurements of the capacitance gradient and voltage in an electronic null balance. As we approach the nanonewton regime, the finite stiffness

NIST Electrostatic Force Balance Experiment

January 1, 2002

Author(s)

John A. Kramar, David B. Newell, Jon R. Pratt

We have designed and built a prototype electrostatic force balance for realizing forces in the micronewton range. The active electrodes are concentric cylinders, the outer serving as the reference and the inner suspended and guided by a rectilinear flexure

SI Traceability of Force at the Nanonewton Level

July 1, 2001

Author(s)

David B. Newell, Jon R. Pratt, John A. Kramar, Douglas T. Smith, L. A. Feeney, Edwin R. Williams

Although nanonewton force measurements are commonplace in industry, no National Measurement Institute supports a link to the International System of Units (SI) below one newton. The National Institute of Standards and Technology has launched a five-year