Keithley 4200A-SCS

Model 4200A
-SCS Parameter Analyzer Reference Manual Section 4: Multi-frequency capacitance-
voltage unit
4200A-901-01 Rev. C / February 2017 4-87
Formulas and constants
This project uses two formulas, described in the following topics. There are no constants.
Formula: CAVG
Formula name: CAVG
Units: F
Description: Calculates the average capacitance.
Formulator entry:
CAVG = AVG(CP_AB)
Formula: STD_DEV
Formula name: STD_DEV
Units: None
Description: Calculates the standard deviation of the capacitance measurements.
Formulator entry:
STD_DEV = STDEV(CP_AB)
cv-gd and cv-sd tests
cv-gd test: This test measures C-V (gate to drain at 1 MHz) on a nanowire device on a wafer or a
discrete nanowire device. It generates a C versus V graph.
cv-sd test: This test measures C-V (source to drain at 100 kHz) on a nanowire device on a wafer or
a discreet nanowire device. This test generates a C versus V graph and calculates average
capacitance and standard deviation.
Both tests are configured the same except for the drive frequency.
cv-gd and cv-sd Analyze sheet
The test data is displayed in the Analyze sheet:
• Cp_AB: Measured parallel capacitance.
• Gp_AB: Measured conductance.
• DCV_AB: Forced DC bias voltage.
• F_AB: Forced test frequency.
• CVU1S: Status code for each measurement. Rows highlighted in blue indicate a fault. For details,
see Measurement status (on page 6-191
).
• Formulas: Formulator calculation results (cv-sd test only).
AB = Terminal A to Terminal B.