Keithley 4200A-SCS

Model 4200A
-SCS Parameter Analyzer Reference Manual Section 4: Multi-frequency capacitance-
voltage unit
4200A-901-01 Rev. C / February 2017 4-97
Formula: PMAX
Formula name: PMAX (P
MAX
)
Units: W
Description: Maximum power point.
Formulator entry:
PMAX = MAX(P)
Simplified equation:
P
MAX
= I
MAX
x V
MAX
Formula: VMAX
Formula name: VMAX
Units: V
Description: Cell voltage where the power output of the cell is greatest (PMAX).
Formulator entry:
VMAX = AT(ANODEV, MAXPOS(P))
Formula: VOC
Formula name: VOC (V
OC
)
Units: V
Description: Open circuit voltage. VOC is the point in I-V data where I = 0.
Formulator entry:
VOC = AT(ANODEV, FINDU(ANODEI, 0, LASTPOS(ANODEI)))
Constants for the solarcell project
Constant Default value Units Description
AREA
8
cm
2
Gate area of device
ES
1.034e-12
F/cm
Semiconductor permittivity (ε
S
)
fwd-ivsweep test
Make sure the PV cell is connected to the 4200-SMU (see Connections (on page 4-94)).
This test uses a 4200-SMU to perform a forward-biased voltage sweep on a PV cell. Current is
measured on each step of the sweep. An I versus V graph is generated from the collected data. It
also makes Formulator calculations to determine the electrical characteristics of the cell.
When the test is started, the SMU sweeps from −50 mV to 250 mV in 2 mV steps. A total of 151
current measurements are made.