User`s guide

Agilent EasyEXPERT User’s Guide Vol. 1, Edition 1 4- 45

Function Details

SMU CMU Unify Unit

Only for the B1500A. The SMU CMU Unify Unit (SCUU) is available for the

B1500A installed with the multi frequency capacitance measurement unit

(MFCMU). The MFCMU must be installed in the slot N (integer, 3 to 10) and the

SMUs must be installed in the slot N-1 and N-2. See Agilent B1500A User’s Guide

to install the SCUU properly. The SCUU cannot be connected to the high power

SMU (HPSMU).

The Guard Switch Unit (GSWU) controls the connection of the CMU High and Low

guard lines (CMU return). The connection will be broken when using the SMU and

made when using the MFCMU.

The SCUU can switch the measurement resources, MFCMU or SMU, and can

configure four setups shown in

Figure 4-21. When the B1500A is turned on, no

measurement resource is connected to the output. The SCUU has input connectors,

four coaxial and four triaxial, connected to the MFCMU and SMU directly or by

using the dedicated SCUU cable.

The SCUU front panel LEDs indicate the following conditions of the SCUU.

SMU SMU in the slot N-1/N-2 can be used.

CMU Internal Bias MFCMU can be used. CMU internal DC bias source is used.

CMU SMU Bias MFCMU can be used. SMU is used as DC bias source.

The SCUU has output connectors, four triaxial, that must be connected to the DUT

interface such as manipulators and probe card. When the measurement resource is

the SMU, they are the Force1/Sense1 and Force2/Sense2 connectors for the Kelvin

connection. And when the resource is the MFCMU, the CMU High/Low are

connected to the Force1/Force2 respectively, and the Sense1/Sense2 are not used.

To realize accurate impedance measurements, connect the CMU return terminals

together. The CMU return terminal means the shield end of the outer shield

conductor extended to the DUT interface. The shield end must be opened as close as

possible to the DUT. See

Figure 4-14 on page 4-26.

The GSWU has one connector and two terminals. The connector must be connected

to the SCUU by using the SCUU cable. And the terminals must be connected to the

CMU High/Low guard lines at the shield ends of the DUT interface by using a wire.