Keithley 7174A, Инструкция по эксплуатации

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3
Applications
3-1
3.1 Introduction
This section covers typical applications for the Model 7174A
8
×
12 Low Current Matrix Card and is organized as follows:
3.2 CV measurements —
Outlines the test configuration
and procedure for making quasistatic and high-
frequency CV measurements.
3.3 Semiconductor test matrix —
Details a semiconduc-
tor test matrix that can be used to perform a variety of
different tests on semiconductors such as FETs.
3.4 Resistivity measurements—
Covers methods to mea-
sure the resistivity of semiconductor samples using the
van der Pauw method.
3.5 Semiconductor IV characterization —
Covers the
basic scheme and connections used to generate an IV
curve of a bipolar or MOS transistor.
3.2 CV measurements
The Model 7174A can be used in conjunction with the
Keithley Model 590 CV Analyzer, and the Keithley Model
595 Quasistatic CV Meter to perform quasistatic and high-
frequency CV (capacitance vs. voltage) test on
semiconductors. The resulting CV curves can be used to
calculate important semiconductor parameters such as
doping profile, band bending, and mobile ion concentration.
3.2.1 Stand alone system configuration
The stand alone system shown in Figure 3-1 can be used to
make CV measurements without the aid of a computer. Sys-
tem components perform the following functions.
Model 590 CV Analyzer:
Measures CV data at 100kHz and
1MHz and sends the resulting data to the plotter for
graphing.
Model 595 Quasistatic CV Meter:
Measures quasistatic CV
data and sends the data to the plotter for graphing in real
time.
Model 707A Switching Matrix:
Controls the semiconductor
matrix card to close and open the desired crosspoints at the
proper time.
Model 7174A 8
×
12 Low Current Matrix Card:
Switches
the signa pathways to the six devices under test.
HP-GL Plotter:
Plots CV and other curves directly from the
Models 590 and 595.
3.2.2 Computerized system configuration
Figure 3-2 shows a computerized version of the CV matrix
test system. The addition of a computer allows greater sys-
tem versatility and easier instrument control. Also, analysis
functions such as doping profile and ion concentration can be
added to the software to expand CV analysis capabilities.
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