Section 4: Multi-frequency capacitance-voltage unit
Model 4200A-SCS Parameter Analyzer Reference Manual
4-56
4200A-901-01 Rev. C / February 2017
moscap-dopingprofile test
This test generates a doping profile, which is a plot of the doping concentration versus depletion
depth. The difference in capacitance at each step of the gate voltage is proportional to the doping
concentration. The depletion depth is computed from the high-frequency capacitance and oxide
capacitance at each measured value of the gate voltage. The results are plotted on the graph.
The doping concentration (
N
) is calculated in the
moscap-c-2vsv
test. The depletion depth (
W
),
which is called
DEPTHM
in the Formulator, is computed from the high frequency capacitance and the
oxide capacitance at each measured value of the gate voltage (from Nicollian and Brews, p. 186; see
(on page 4-63)). The program computes each
W
element of the calculated data array as
shown below:
Where:
•
W = depth (m)
•
A = gate area (cm
2
)
•
C = measured capacitance (F)
•
ε
s
= permittivity of the substrate material (F/cm)
•
C
ox
= oxide capacitance (F)
•
1xE
-2
= units conversion from cm to m
moscap-dopingprofile Analyze sheet
The test data is displayed in the Analyze sheet:
•
Cp_GB: Measured parallel capacitance.
•
Gp_GB: Measured conductance.
•
DCV_GB: Forced DC bias voltage.
•
F_GB: Forced test frequency.
•
CVU1S: Status code for each measurement. Rows highlighted in blue indicate a fault. For details,
see
(on page 6-191).
•
Formulas: Formulator calculation results.
GB = gate-to-bulk.
