Agilent Technologies EasyEXPERT, Manual, Page: 68 / 610

2 CMOS
2.3 Cgb-AC Level: Cgb-Vosc characteristics (A.01.11)
[Supported Analyzer]
B1500A
[Description]
Measures the Gate-Substrate capacitance (Cgs), and plots the Cgs-Vosc characteristics.
DC bias output is fixed at -Vgs. Oscillator level (Vosc) is changed from -OscStart to -OscStop in -OscStep
steps. The CMU performs spot measurement of the parallel capacitance (Cp) and conductance (G) at each
oscillator level.
For a more accurate measurement, perform correction data measurement at the measurement frequency before
starting the capacitance measurement.
If the measurement frequency is not included in the list of default frequencies below, click the Advanced
Options... button and set the measurement frequency on the Frequency area of the Advanced Options for CMU
Calibration window.
Default frequencies:
1 k, 2 k, 5 k, 10 k, 20 k, 50 k, 100 k, 200 k, 500 k, 1 M, 1.2 M, 1.5 M, 2 M, 2.5 M, 2.7 M, 3 M, 3.2 M, 3.5 M,
3.7 M, 4 M, 4.2 M, 4.5 M, 5 MHz
[Device Under Test]
MOSFET, 4 terminals
Connect Gate to the CMU Low and Substrate to the CMU High. And connect Drain and Source to the
specified SMU.
[Device Parameters]
Polarity: Nch (CMU/SMU forces the specified value) or Pch (CMU/SMU forces the negative specified value).
Lg: Gate length
Wg: Gate width
Temp: Temperature
[Test Parameters]
IntegTime: Integration time
OscStart: Oscillator level (Vosc) start voltage
OscStop: Vosc stop voltage
OscStep: Vosc step voltage
FREQ: Measurement frequency
Gate: CMU connected between Gate and Substrate (CV spot measurement)
Vgs: DC bias. Gate-Substrate voltage.
Source: SMU connected to Source terminal (constant voltage output)
[Extended Test Parameters]
Vs: Source voltage
IsLimit: Source current compliance
HoldTime: Hold time
DelayTime: Delay time
[Measurement Parameters]
Parallel capacitance cp
Conductance g
[User Function]
PI=3.141592653589
d=g/(2*PI*FREQ*cp)
Agilent EasyEXPERT Application Library Reference, Edition 8
2-6