Making Stable Measurements With Smus; Single Smu Stability Considerations - Keithley 4200A-SCS Reference Manual

Section 12: Maintenance

Making stable measurements with SMUs

The following topics discuss various considerations when making stable measurements, including
single-SMU stability, multiple-SMU stability, and avoiding oscillation.

Single SMU stability considerations

Driving inductive loads can cause current source instability. Current source instability almost never
occurs in semiconductor applications.
A SMU that is sourcing voltage is stable when driving capacitive loads up to 10 nF. However, at the
lower current measurement ranges, large capacitive loads may increase settling time and may cause
overshoot and ringing. To reduce this effect, you can add a small resistor in series with the capacitive
load. Choose a resistor that provides an R
You can also increase the measurement delay factor for the test to reduce this effect:
1. In Clarius, select the test.
2. Select Configure.
3. In the right pane, select Test Settings.
4. Select Advanced.
5. Set the Speed to Custom.
6. Increase the Delay Factor.
Refer to Delay Factor
12-8
time constant of 1 ms to 10 ms.
C
(on page 6-84) for additional information.
Model 4200A-SCS Parameter Analyzer Reference Manual
4200A-901-01 Rev. C / February 2017