A Tektronix Company
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• Measures resistances up to 10
18
Ω
• 10aA (10×10
–18
A) current
measurement resolution
• <3fA input bias current
• 6½-digit high accuracy
measurement mode
• <20µV burden voltage on the
lowest current ranges
• Voltage measurements up to 200V
with >200T
Ω
input impedance
• Built-in ±1000V voltage source
• Unique alternating polarity voltage
sourcing and measurement
method for high resistance
measurements
• Built-in test sequences for four
different device characterization
tests, surface and volume
resistivity, surface insulation
resistance, and voltage sweeping
• Optional plug-in scanner cards for
testing up to 10 devices or material
samples with one test setup
APPLICATIONS
• Polymer electrical characterization
• Beam measurements
• Dosimetry
• Device leakage current
measurements
• Insulation resistance
measurements
• Optoelectronic detector
characterization
• Volume and surface resistivity
• Nanomaterial characterization
The Keithley 6517B Electrometer/High Resistance Meter is
the worldwide research laboratory standard for sensitive
measurements. With over 60 years of low level measurement
expertise, Keithley electrometers provide reliable measure-
ments of current levels down to 10aA (10×10
–18
A,) charge
levels down to 1fC, and the highest resistance measurements
available up to 10
18
Ω
. The 6517B is also capable of meas-
uring the largest voltage range—up to 200V—with an input
impedance exceeding 200T
Ω
.
Exceptional Performance Specifications
The 6517B has incorporated Keithley’s decades of expertise
in low level measurement technology into an innovative, low
current input amplifier with an input bias current of <3fA,
just 0.75fAp-p noise, and <20µA burden voltage on the low-
est current ranges. The voltage circuit input impedance is greater than 200T
Ω
for near-ideal circuit
loading. These specifications ensure the accuracy and sensitivity needed for accurate low current and
high imped ance volt age, resistance, and charge measure ments in areas of re search such as physics,
optics, nanotechnology, and materials science. A built-in ±1kV voltage source with sweep capability
simplifies performing leak age, break down, and resis tance testing, as well as volume (
Ω
-cm) and sur-
face resistivity (
Ω
/square) mea sure ments on insulating materials.
Wide Measurement Ranges
The 6517B offers autoranging over the full span of ranges on current, resistance, voltage, and charge
measurements. The 6517B combines the following measurement capabilities:
• Ultra-sensitive ammeter with current measurement from 10aA to 20mA
• Highest impedance voltmeter with voltage measurement from 1µV to 200V
• Ultra-high range ohmmeter with resistance measurement from 1
Ω
to 10
18
Ω
• Sensitive coulombmeter with charge measurement from 1fC to 2µC
Improved High Resistivity Measurements
Many test applications require measuring high levels of resistivity (surface or volume) of materials.
The conventional method of making these measurements is to apply a sufficiently large voltage to
a sample, measure the current that flows through the sample, then calculate the resistance using
Ohm’s Law (R=V/I.) While high resistance materials and devices produce very small currents that are
difficult to measure accurately, Keithley electrometers and picoammeters are used successfully for
such measurements.
Even with high quality instrumentation, inherent background currents in the material can make
these measurements difficult to perform accurately. Insulating materials, polymers, and plastics typ-
ically exhibit background currents due to piezoelectric effects, capacitive elements charged by static
electricity, and polarization effects. These background currents are often equal to or greater than
the current stimulated by the applied voltage. In these cases, the result is often unstable, providing
inaccurate resistance or resistivity readings or even erroneous negative values. Keithley’s 6517B is
designed to solve these problems and provides consistent, repeatable, and accurate measurements
for a wide variety of materials and components, especially when used in combination with the 8009
Resistivity Test Fixture.
Alternating Polarity Method for High Resistance Measurements
The 6517B uses the Alternating Polarity Method, which virtually eliminates the effect of any back-
ground currents in the sample. First and second order drifts of the background currents are also can-
celed out. The Alternating Polarity Method applies a voltage of positive polarity, then the current is
measured after a specified delay (Measure Time). Next, the polarity is reversed and the current meas-
ured again, using the same delay. This process is repeated continuously, and the resistance is calculat-
ed based on a weighted average of the four most recent current measurements. This method typically
produces a highly repeatable, accurate measurement of resistance (or resistivity) by the seventh rever-
6517B
Electrometer/High Resistance Meter
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