Tektronix Keithley 4200A-SCS - Page 167

Model 4200A-SCS Prober and External Instrument Control Section 6: Using a Model 82 C-V System
4200A-913-01 Rev. A December 2020 6-59
G/nI computation
Where:
• G = generation rate (s
-1
)
• 
S
= permittivity of semiconductor (F/cm)
• A = gate area (cm
2
)
• N
AVG
= average doping concentration (cm
-3
)
• C
OX
= oxide (maximum) capacitance (pF)
• C
t(i+1)
= (i+1) value of measured C-t capacitance (pF)
• C
t(i-1)
= (i-1) value of measured C-t capacitance (pF)
• n
I
= intrinsic carrier concentration (cm
-3
)
• t
int
= time interval between C-t measurements (s)
• i = [2, #Rdgs-1]
w - wF computation
Where:
• w = depletion depth (cm)
• w
F
= equilibrium inversion depth (cm)
• 
S
= permittivity of semiconductor (F/cm)
• A = gate area (cm
2
)
• C
ti
= i(th) value of measured C-t capacitance (pF)
• C
MIN
= equilibrium minimum capacitance (pF)