User`s guide

1-30 Agilent 4155C/4156C User’s Guide Vol.2, Edition 6

Sweep Measurements

Making a Measurement

In this section, you learn how to execute the measurements with an 4155C/4156C

and to display the measurement results graphically. Id-Vg measurement of a MOS

FET is provided as an example. You learn step-by-step how to perform this

measurement.

You measure the device under test (DUT) by using the measurement circuit as

shown in the following diagram. SMU2 and SMU3 sweep the same voltage to the

gate and drain. SMU3 measures the drain current (Id). The source and substrate are

connected to circuit common.

You should get result similar to the following figure. Gate voltage Vg (swept from

0 V to 2 V) is assigned to X axis, √ Id

is assigned to Y1 axis, and ∂√ Id / ∂Vg is

assigned to Y2 axis.

NOTE For accurate measurements, allow the 4155C/4156C to warm-up for a minimum of

40 minutes after you turn on the instrument, and then execute calibration. For the

self-calibration, see Chapter 7.