Keithley 4200A-SCS - Page 158

Model 4200A
-SCS Parameter Analyzer Reference Manual Section 4: Multi-frequency capacitance-
voltage unit
4200A-901-01 Rev. C / February 2017 4-65
moscap-lifetime formulas and constants
Tests in this project use the same formulas as the ones for the cvu-moscap project. It also uses
additional formulas (used by the gni-w-wf test) and user-defined constants, which are summarized
in the following tables. The formulas and constants are set from the Formulator for the tests.
Note that results of the C
OX
, C
MIN
, and N
AVG
formulas (used by the c-v test) are needed for the gni-
w-wf test. You must manually input the results into the Formulator for the gni-w-wf test.
When configuring the project, you must input the area of the gate (in units of cm
2
) and the dope type
(−1 for P-type, 1 for N-type) of the device into the Constants area of the Formulator.
Details for referenced equations are in the documentation for
Generation velocity and generation
lifetime (on page D-60).
Formula: GNI
Formula name: GNI (G/ni)
Units: s
-1
Description: Generation rate.
Formulator entry:
GNI = -(ES*AREA*NAVG*COX)*DIFF(MAVG(1/CP^2, 5), TIME)/NI
Simplified equation:
Formula: WF
Formula name: WF (WF)
Units: cm
Description: Equilibrium inversion depth.
Formulator entry:
WF = ES*AREA*(1/MIN(CP_GB)-1/COX)
Simplified equation: