1.1 This test method covers the measurement of the resistivity of a
silicon substrate of known orientation and type, or of a uniform
silicon epitaxial layer of known orientation and type that is
deposited on a substrate of the same or opposite type. Resistivity of
the epitaxial films can be evaluated without the necessity of thin
film correction factors provided that the ratio of layer thickness to
effective probe contact radius is greater than 20.
1.2 This test method is comparative in that the resistivity of an
unknown specimen is determined by comparing its measured spreading
resistance with that of calibration standards of known resistivity.
These calibration standards must have the same surface finish,
conductivity type, and orientation as the unknown specimen.
1.3 This test method is intended for use on silicon substrates and
epitaxial layers. Within-laboratory precision has been determined
through a multilaboratory experiment on substrates having
resistivities from 0.01 to 200 Ω·cm.
1.3.1 The principles of this test method can be extended to lower and
higher specimen resistivity values, but the precision of the test
method has not been evaluated for values other than those in the range
given in 1.3.
1.4 This test method is nondestructive in the sense that the specimen
is not totally destroyed in making the measurements, the specimen need
not be cut into a special shape, and no destructive processing need be
done on the specimen. However, the probe can produce mechanical damage
that may be detrimental to a device fabricated in the probed area.
1.5 The volume of semiconductor material sampled is proportional to
the third power of the effective electrical contact radius of the
probe. For an effective electrical contact radius of 2 μm, the
volume sampled by a single probe is approximately 10−11
1.6 This standard does not purport to address all of the safety
concerns, if any, associated with its use. It is the responsibility of
the user of this standard to establish appropriate safety and health
practices and determine the applicability of regulatory limitations
prior to use.