Agilent Technologies 4339B, Operation Manual

Page: 215 / 287

4339B Resistivity
Resistivity
V olume Resistivity
In general, volume resistivity is dened as the resistance per unit volume .
v
=
Ar ea
t
R
v
2
1
10
where ,
v
V olume resistivity [-cm]
Area Eective area [mm
2
]
t Thickness of the sample [mm]
R
v
Measured volume resistance []
When the 16008B Resistivity Cell is used, the above equation becomes:
v
=
2 D
1
+
B ( D
2
0D
1
)
2
2
4t
2 R
v
2
1
10
Where ,
D
1
Main electrode diameter [mm]
D
2
Guard electrode diameter [mm]
B Eective area coecient
B is the fraction of the gap width to be added to the diameter of the circular electrodes or to
the dimensions of rectangular or cylindrical electrodes . The value is usually specied by the
standard that you use . (F or example: 1 for ASTM D 257; 0 for JIS K6911).
Figure 7-1. V olume Resistivity
Measurement Basics 7-3