This paper reports on a feasibility study in the detection of nanometer thick lubricated regions on a hard disk by a novel use of a Kelvin probe. A nonvibrating Kelvin probe was constructed and used to measure the voltages between the copper surface of the probe and a hard disk partially-lubricated with a perfluoropolyether. The probe, constructed of a shielded 1.6 mm diameter gold-coated copper wire, was fixed above the hard disk and the probe voltage was obtained as a function of the speed of the disk and lubricant thickness. The probe generates an electrical signal as the interface between the lubricated and unlubricated regions is crossed. Results show that the probe can distinguish between regions on the hard disk that contain 3 and 10 nm thick lubricant films.

1.
Baumgartner
H.
, and
Leiss
H. D.
,
1988
, “
Micro Kelvin Probe for Local Work-Function Measurements
,”
Rev. Sci. Instrum.
, Vol.
59
, pp.
802
805
.
2.
Danyluk
S.
, and
Blakely
J. M.
,
1973
, “
Space Charge Regions at Silver Halide Surfaces: Effects of Divalent Impurities and Halogen Pressure
,”
Surface Science
, Vol.
40
, pp.
37
48
.
3.
Davies
D. K.
,
1967
, “
The Examination of the Electrical Properties of Insulators by Surface Charge Measurement
,”
J. Sci. Inst.
, Vol.
44
, pp.
521
524
.
4.
Devins
J. E.
, and
Reynolds
S. I.
,
1957
, “
Rotating Probe Electrometer
,”
Rev. Sci. Inst.
, Vol.
28
(
1
), pp.
11
13
.
5.
Engelhardt
H. A.
,
Feulner
P.
,
Pfnur
H.
, and
Menzel
D.
,
1977
, “
An Accurate and Versatile Vibrating Capacitor for Surface and Adsorption Studies
,”
J. Phys. E.: Sci. Instrum.
, Vol.
10
, pp.
1133
1136
.
6.
Harris
L. B.
, and
Fiasson
J.
,
1984
, “
Vibrating Capacitor Measurements of Surface Charge
,”
J. Phys. E.: Sci. Instrum.
, Vol.
17
, pp.
788
792
.
7.
Lord Kelvin, Fitzgerald, G. F., and Francis, W., 1898, “Contact Electricity of Metals,” Phil. Mag., pp. 80–120.
8.
Novotny
V. J.
,
Karis
T. E.
, and
Whitefleld
R. J.
,
1997
, “
Surface Potential and Magnetic Recording Media Tribology
,”
Tribology Transactions
, Vol.
40
, pp.
69
74
.
9.
Streator
J. L.
, and
Johnson
J. K.
,
1994
, “
Velocity-Dependent Adhesion with Lubricants on Thin Film Disks
,”
Tribology Transactions
, Vol.
37
(
4
), pp.
864
870
.
10.
Wolff
M.
,
Guile
A. E.
, and
Bell
D. J.
,
1969
, “
Measurement of Localized Surface Potential Difference
,”
J. Sci. Inst. (J. Phys. E)
, Vol.
2
(
2
), pp.
921
924
.
11.
Zanoria
E. S.
,
Hamall
K.
,
Danyluk
S.
, and
Zharin
A. L.
,
1995
, “
Surface Wear Monitoring with a Non-Vibrating Capacitance Probe
,”
J. Korean Soc. Trib. and Lub. Engineers
, Vol.
11
(
5
), 12 Special Issue, pp.
40
46
.
12.
Zanoria
E. S.
,
Danyluk
S.
,
Zharin
A. L.
, and
Bhatia
C. S.
,
1996
, “
Contact Potential Difference Measurements of Hard Disk Drive Surfaces in Humid Environinents
,”
J. Vac. Sci. Technology
, Vol.
A14
(
1
), pp.
52
55
.
13.
Zanoria
E. S.
,
Hamall
K.
,
Danyluk
S.
, and
Zharin
A. L.
,
1997
, “
The Nonvibrating Kelvin Probe and its Application for Monitoring Surface Wear
,”
J. Testing and Evaluation
, Vol.
25
(
2
), pp.
233
238
.
14.
Zisman
W. A.
,
1932
, “
A New Method of Measuring Contact Potential Differences in Metals
,”
Review Sci. Instr.
, Vol.
3
(
7
), pp.
367
37
.
This content is only available via PDF.
You do not currently have access to this content.