Demo Project (Default); Carbon Nanotube Transistor Characterization Project (Cntfet-Characterization) - Keithley 4200A-SCS Reference Manual

Section 4: Multi-frequency capacitance-voltage unit

Demo project (default)

The tests in this project represent the most common device tests.
The tests in the default project that use the CVU are cv-nmosfet, cv-diode, and cv-cap.
cv-nmosfet test
Measures the capacitance as a function of the gate voltage between the gate terminal and the drain,
source, and bulk terminals tied together. Several parameters are extracted, including the flatband
capacitance, doping density, flatband voltage, and oxide thickness.
cv-diode test
Measures the junction capacitance as a function of an applied voltage sweep. The depletion depth
(W) and the doping density (N) are calculated as a function of the C-V data.
cv-cap test
Measures the capacitance as a function of time on a capacitor. The noise is calculated using the
standard deviation of the data.
Carbon Nanotube Transistor Characterization Project
(cntfet-characterization)
This project contains DC I-V, pulsed I-V, and C-V tests for a carbon nanotube FET (CNTFET).
The DC I-V tests include measurements for drain current versus drain voltage (V
voltages and drain current versus gate voltage (V
The pulsed I-V tests include pulsed V
The C-V test includes a C-V sweep test that measures the gate-to-drain capacitance as a function of
the gate voltage of a CNTFET.
The tests include:
•
CNTFET Drain Family of Curves (vds-id-cntfet): This test generates the standard family of drain
current versus drain voltage curves on a FET. For each gate voltage step, the test sweeps the
drain voltage and measures the resulting drain current. This test uses either three or four SMUs
that are connected to the gate, drain, source, and bulk terminals of the FET.
•
CNTFET Drain Current versus Gate Voltage (vgs-id-cntfet): This test sweeps the gate voltage
(V ) and measures the resulting drain current (I
g
•
CNTFET Capacitance versus Voltage Sweep (cvsweep-cntfet): Measures the gate-to-drain
capacitance as a function of the gate voltage of a carbon nanotube FET. The test is made at a
constant test frequency.
•
CNTFET Pulsed Drain Family of Curves (pulsed-vds-id): Uses CH1 and CH2 of a PMU to
generate a pulse I-V drain family of curves. CH1 outputs a pulse step output to the gate. CH2
outputs a pulsed drain voltage sweep and measures the drain current.
•
CNTFET Single Pulse I-V (cnt-pulse): The waveform capture mode of the PMU shows the time-
based response of the drain current and drain voltage of a CNTFET. CH1 outputs a single pulse
to the gate. CH2 captures the transient response of the drain current and drain voltage.
4-100
Model 4200A-SCS Parameter Analyzer Reference Manual
) at a constant drain voltage.
gs-Id
and pulsed V .
ds-Id gs-Id
) while the drain voltage (V
d
) at stepped gate
ds-Id
) is kept constant.
d
4200A-901-01 Rev. C / February 2017