Surface profilometer, consisting primarily of commercially available components, measures surface topographical features accurately and precisely. It shows improvement over the interferometric technique in measurement of grain-boundary grooves formed during annealing on nickel-oxide bicrystals

Jech, R. E.

Ready, D. W.

English

NASA Technical Reports Server

August 1969	 Brief 69-10345 
• Say Co.,
AEC-NASA TECH BRIEF 
AEC-NASA Tech Briefs describe innovations resulting from the research and development program 
of the U.S. AEC or from AEC-NASA interagency efforts. They are issued to encourage commercial 
application. Tech Briefs are published by NASA and may be purchased, at 15 cents each, from 
the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Surface Prof ilometer for Examining

Grain-Boundary Grooves 
.
The problem: 
To develop an accurate and precise technique for 
measuring topographical features on the surfaces of 
solids. The most accurate and commonly used tech-
nique for this purpose has been interference micros-
copy. This technique, however, requires corrections 
for illumination conditions, and the profile of a sur-
face feature is greatly exaggerated in the vertical 
direction; thus the accuracy of the technique is un-
satisfactory for measurement of profiles such as grain-
boundary grooves in which the width-to-depth ratio 
is roughly 10:1 or less. 
The solution: 
A surface profilometer, consisting primarily of 
commercially available components, measures surface 
topographical features accurately and precisely. The 
apparatus permits horizontal magnification by roughly 
10,000X and vertical magnification by 100,000x, 
and can give a 1:1 ratio at 10,000X or more. Ap-
plication of the technique to grain-boundary grooves 
formed during annealing on nickel-oxide bicrystals 
indicates that it improves by at least an order of 
magnitude the measurement of shape and size of 
groove profiles by the commonly used interferometric 
technique. 
How it's done: 
A diamond stylus having a radius of about 1 /-tm 
traverses the surface of the sample, and its vertical 
deflection and horizontal movement are measured 
electrically. The primary component is a surface pro-
filometer including a parallel datum attachment. This 
unit was originally designed to inspect surface finishes
of machined parts; it has also been used to measure 
thicknesses of thin films for microcircuit applications. 
The available unit is capable of only 500X hori-
zontal magnification; thus a linear strain-gage trans-
ducer, with a total travel of 0.12 mm, is used to 
measure horizontal displacement of the stylus arm. 
The output of the profilometer is the input for the 
y-axis of an x-y recorder; that of the strain-gage 
transducer, for the x-axis. The output of both the 
profilometer and the linear transducer is 5 v full 
scale, which provides almost infinite magnification 
on the most sensitive range of the recorder (0.1 
mv/inch). However, the mechanical limitation 
of vibration, sample positioning, calibration, and 
instabilities in the traversing motion of the stylus 
place the upper practical limit on both x and y 
magnifications at roughly 100,000X. The magni-
fied profile of the surface is conveniently reproduced 
on 8½-by-i 1-inch graph paper. 
The apparatus has been further modified to pro-
vide manual traversing of the stylus arm by means 
of a 600:1 speed-reducer and a handwheel. This 
change adds the flexibility of traversing both forward 
and backward across the surface feature, and simpli-
fies positioning of the stylus at the desired point on 
the surface of the sample. The fact that the sample 
is mounted on a two-axis micrometer translation 
stage having a total travel, of 0.5 inch and a sensi-
tivity of 0.0001 inch in both directions further aids 
positioning of the sample. This micrometer stage 
also allows traversing along the length of a surface 
feature, such as a grain-boundary groove, to obtain 
profiles, at various positions, giving a three-dimen-
sional profile of the groove. The strain-gage trans-
(continued ovcrleat) 
This document was prepared under the sponsorship of the Atomic 
Energy Commission and/or the National Aeronautics and Space 
Administration. Neither the United States Government nor any per-
son acting on behalf of the United States Government assumes any
liability resulting from the use of the information contained in this 
document, or warrants that the use of any information, apparatus, 
method, or process disclosed in this document may not infringe pri-
vately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19690000344 2020-03-16T18:12:33+00:00Z
ducer is mounted on a single-axis translation stage 
having a total travel of 0.05 inch and a sensitivity of 
5 microinches. This allows accurate zeroing and cen-
tering of the profile on the recorder, and enables cali-
bration of the x-traverse. The vertical calibration is 
obtained from standards provided with the profilom-
eter. Finally, to reduce vibration, the apparatus 
is mounted on a granite tabletop supported by air 
pistons. 
Reference: 
For more detail see D. W. Ready and R. E. Jech, 
J. Amer. Ceram. Soc. 51 (4) (April 1968). 
Notes: 
1. This information may be of interest in the fields 
of metallurgy, mineralography, electronics, and 
ceramics.
2. Inquiries may be directed to: 
Office of Industrial Cooperation 
Argonne National Laboratory 
9700 South Cass Avenue 
Argonne, Illinois 60439 
Reference: B69-10345 
Source: D. W. Ready and R. E. Jech

Metallurgy Division

(ARG- 10290) 
Patent status: 
Inquiries concerning rights for commercial use of 
this innovation may be made to: 
Mr. George H. Lee, Chief 
Chicago Patent Group 
U.S. Atomic Energy Commission 
Chicago Operations Office 
9800 South Cass Avenue 
Argonne, Illinois 60439 
Brief 69-10345	 Category 05


Surface profilometer for examining grain-boundary grooves

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