Keithley 2450 - Internal Manual

Please read the General Presentation of ECR prior to reading this manual to understand the basics of ECR measurement.

Please also read the Customer Manual of Keithley 2450 prior to reading this manual to understand the basics of Advanced ECR using Keithley 2450.

General Presentation

Keithley 2450 front panel with specificities highlighted.

The main components of the front panel useful for setting up the Keithley 2450 are the following:

Control knob: Can be used to modify a value selected.

Touch Display: The display screen is a touch screen.

Control buttons: The buttons allow the user to access the different parameters of the Keithley.

Terminal switch: The button switches the active terminals from the front to the back. If the banana are plugged into the front terminals, the switch needs to be set to “F”.

Additional information available in “Front-panel overview” part of Keithley 2450 – Reference Manual (p.70-72)

*Keithley 2450 rear panel with specificities highlighted.*

The main components of the rear panel useful for setting up the Keithley 2450 are
the following:

Fuse: If the voltage or current are not within specifications, the fuse may blow
up, it would then need to be replaced.

100-240VAC inlet: The instrument needs to be powered by a voltage withing
the range.

USB port: A short USB A to USB B cable should be delivered with the Keithley
2450. It can be used to connect the Keithley to the instrument. This
communication method can be used if LAN communication is not ideal for the
instrument.

RJ45 port: It is possible to communicate by LAN using an RJ45 cable (Provided
by Keithley). This is the recommended communication method as it involves
less steps.

Additional information available in “Rear panel overview” part of Keithley 2450 – Reference Manual (p.72-73)

MFT Software communicates with the Keithley 2450 using SCPI set of commands. This mean of communication is introduced in “Introduction to SCPI” part of “Keithley 2450 – Reference Manual” (p.387-395). The specific SCPI commands are detailed in the following pages: p.396-601.

First installation : Setting Up Communication

USB or Ethernet

Select the Data Communication type depending on the instrument: (and cable type available)

Data Communication Type:	LAN (Ethernet)	USB
Cable type:	RJ45	USB A to B
Recommended on:	MFT-5k (connection to Ethernet hub at motion box back)	MFT-2k (Direct communication to PC)

Setting Up Ethernet Communication (LAN)

Setting Up the Keithley

Plug the RJ45 cable to the RJ45 port for LAN communication of the Keithley.

Plug the other end into the ethernet hub of the MFT-5k.

Turn on the Keithley

Press the MENU button.

Under System select Communication, then LAN tab.

*Menu window to access communication menu.*

Lan Tab setting

For “TCP/IP Mode”, select “Manual”.

For “Gateway”, enter “192.168.0.41”.

For “IP Address” enter “192.168.0.41”.

For “Subnet”, enter “255.255.255.0”.

Select “Apply Settings” to save your settings.

Press on “Output” on the front panel. It should become blue.

Wait for the LAN status indicator on the top right of the front panel of the Keithley to turn solid green.

Note that it may take several minutes for the computer and instrument to establish a connection.

Ensuring Static IP Address Is Set

On the PC

Seach network in windows.

Go to IPv4 eternet properties.

Under Network and Sharing Center

Select View network Status and Tasks

On the left, choose Change Adapter Settings and right-click on Ethernet

Click on Properties and select Internet protocol version 4 (tcp/ipv4)

Use the following 192.168.00.1 ip adress.

Press Enter to use the default subnet mask.

Press Enter again.

Setting Up USB Communication

For USB Communication, the Keithley I/O layer software must be downloaded and installed.

It is required to create a Tektronix account to proceed with the download.

Keithley I/O Layer software download:

Download the following software: (Verify that it is not outdated)

KIOL-850C10_signedJun2023.zip

497.2 MiB

Or search on the internet for “Keithley I/O Layer” software, download it, then install it on the PC.

Setting Up the Keithley

Connect Type B end of the cable to the Keithley.

Connect the Type A end of the cable to the PC.

USB 2.0 or 3.0 are fine.

Turn on the Keithley.

Wizard Configurator

In Windows search bar, type Keithley Configuration Panel

Select Add, and click Next

Select USB, and click Next

Select Auto-detect Instrument Driver – Model and click Next.

Auto-detected resulting ANY is fine.

Optionally rename the Keithley and click Next.

Select the Keithley from the list and click Next.

If no instrument appears in the list

Go to Device Manager

Remove and plug back the USB cable

Verify if any new item appears in the manager and Identify where it is located.

If the Keithley is not detected:

Change the USB port on the PC.
Replace the USB cable.

If there is a driver error, ensure that you downloaded the latest Keithley I/O Layer software.

Click Finish.

Close the Wizard.

Save the configuration. From the Keithley Configuration Panel, select “File” > “Save”.

Plug the Measurement Cable

Plug the 2 black and 2 red banana cables into the connectors.

Ensure that the green LED with the letter F is on (for front banana terminals) and not the yellow R (for rear banana terminals).

If R is on, press once on the Terminal button.

Enabling Keithley Control in MFT and Adding Commands to Your Recipe

Launch MFT Software.

Go to Config and select Keithley and Keithley 2450 under Corrosion.

If Keithley 2450 is not present

Go to C:\ProgramData\Rtec

If not present, add the following in the “Components.xml” file:


<Components>
	<Component>Keithley</Component>
	<Group>Corrosion</Group>
	<Available>True</Available>
	<ClassName>Keithley.clsAddIn</ClassName>
	<Address>COM31</Address>
</Components>

If not present, add the following in the “ComponentOptions.xml” file:


<ComponentOptions>
	<Component>Keithley</Component>
	<Name>Keithley2450</Name>
	<ConfigFile>Keithley2450.xml</ConfigFile>
</ComponentOptions>

If not present, download and paste the following Keithley2450.xml file into C:\ProgramData\Rtec

Keithley2450.xml

1.5 KiB

Press on Save Configuration.

MFT starting status should detect the Keithley 2450.

The keitlhey Model is properly detected and ready to use.

If USB failed Initalization

⚠️

Ensure that TCIP is defined to True in the configuration section

Verify the communication with the Keithley2450

In Windows search bar type Keithley Communicator.

Select File > Open Instrument

Select the instrument you just created

Click Ok

Write the following:

*IDN?

Press the Run Command Button to send the request.

Undefined SCPI Header → Verify the previous syntax request entered

Still no response using the correct syntax → Ensure SPCI Communication is enabled in the keithley

Press the MENU button.

Menu window to access system settings menu.

Under “System”, select “Settings”.

In “Command Set”, select “SCPI”.

Once the Command Set is set to SCPI, you can start connecting your Keithley to the PC using your preferred mean of communication.

The Keithley 2450 should return the instrument information if the communication is effective.

Return to the Config Section from step 2.

Modifiy 2 lines in the CustomCmd3 Control Current or CustomCmd4 Control Voltage table.

For CustomCmd3 Control Current

Edit the SOUR:CURR: …. by replacing the “…” with your desired current value (A) then press ENTER.

Edit the SOUR:VLIM: …. by replacing the “…” with your desired voltage limit (V) then press ENTER.

Alternatively, delete this line to remove the voltage limitation.

For CustomCmd4 Control Voltage

Edit the SOUR:CURR: …. by replacing the “…” with your desired voltage value (V) then press ENTER.

Edit the SOUR:VLIM: …. by replacing the “…” with your desired current limit (A) then press ENTER.

Alternatively, delete this line to remove the current limitation.

Press WRITE, then READ to confirm the changes now appear in the right read table.

An exhaustive list and details of commands used, along with additional ones, can be found in the more advanced manual.

(Optional) You can test and verify the proper request activation by pressing the desired custom command while observing the Keithley.

The custom command 4 sent to the keihtley.

Go to your testing recipe

Select the Standard step you are using for the test.

Click on E-Test: The 4 CustomCommands are available here.

If the E-test Action list doesn't show the 4 commands correctly or shows an old list

Download and paste the following Keithley2450.xml file into C:\ProgramData\Rtec

Keithley2450.xml

1.5 KiB

Select either Control Current or Control Voltage.
The command with your modified value will be sent at the start of this step.

You can enable one of the four commands in an individual step by following the same operation steps.

In the data-logging section, add the 4Ohm component to obtain the resistance measurement and save it to your data result file.

Advanced ECR Measurement

To modify the options of the advanced ECR, you need to go back to the Configuration window and click on “CONFIG” next to the Keithley selected. The following window will appear:

If it does not appear in the configuration:

Download the following xml file:

Keithley2450.xml

1.4 KiB

Paste it in the ProgramData.

If not present, modify Components.xml to add the following lines:

<Components>
<Component>Keithley</Component>
<Group>Corrosion</Group>
<Available>True</Available>
<ClassName>Keithley.clsAddIn</ClassName>
<Address>COM31</Address>
</Components>

If not present, modify ComponentOptions.xml to add the following lines:

<ComponentOptions>
<Component>Keithley</Component>
<Name>Keithley 2450</Name>
<ConfigFile>Keithley2450.xml</ConfigFile>
</ComponentOptions>

The window can be divided into 4 parts:

Identification Window:

COM: If the Keithley communicates by a COM Port, will display here the COM Port used.

Address:

…:

Commands Window:

UserID:

ConnectCmds: The commands that will be sent when the software starts. The instrument will return “KEITHLEY INSTRUMENTS, MODEL nnnn, xxxxxxxx, yyyyyy” (nnnn is the model number / xxxxxxxx is the serial number / yyyyyy is the firmware revision level)

CustomCmd(1/2/3/4): To modify the content of the command sent, you need to modify the content of “CustomCmd(1/2/3/4)”.

CC(1/2/3/4)Display: To modify the name that appears during the recipe creation, you need to modify the content of “CC(1/2/3/4)Display”.

StatusCmd:

IsTCP: This command needs to be set to “True” if the Keithley is communicating with the PC through a LAN interface (Part 2.2.2).
Otherwise, can be set to “False”

Commands Update:

Write and Read: If you enter a command on a line of the “Write” Column, by pressing “Write”, then “Read”, the line in the “Read” column will be automatically updated.

Commands Control:

UPDATE STATUS: The commands retrieve live data from the Keithley (Voltage, Resistance and Temperature). The temperature may not work properly.

CUSTOM CMD (1/2/3/4): This prepares the specific custom command that is entered in the field on the left. By clicking on “Send command”, the command will be activated

RESET: Writes a *RST command that resets the instrument settings to their default values and clears the reading buffers.

SEND: Sends the command that has been written in the free field above the button

SEND COMMAND: Sends the custom command that has been selected previously.

Advanced ECR Command control

Introduction

To create a new command, please note the following rules:

Commands execute in the order that they are presented in the command message.

You should set the measure function first, then set the source function, because setting the measure function may change the source function.

Valid commands that precede an invalid command in a command message are executed. Valid commands that follow an invalid command in a command message are ignored.

When setting a range, you should first set the limit to a value higher than the measure range you intend to set.

The command words are separated by colons (:). A proper command must have the letters in caps. The others are optional.

Example: “SYSTem:COMMunication:LAN:CONFigure AUTO”. This equals to “SYST:COMM:LAN:CONF AUTO”. It starts from the general parameter (the system) to the more specific one (configuration).

Making resistance measurements

Resistance Measurement Methods

From a remote interface, you can use one of the following methods to measure resistance with the Model 2450:

For most samples: Set the measure function to resistance. When the measure function is set to resistance, the instrument sets the source current and source values automatically.

For high resistance samples: Source voltage, measure current, and set measure units to ohms

For low resistance samples: Source current, measure voltage, and set measure units to ohms

Measure resistance using resistance function

When the measurement function is set to resistance, the Model 2450 measures resistance by sourcing current. The instrument automatically sets the magnitude of the current source, voltage limit, and the measure range.

This is the easiest method to measure resistance of the device under test and can be used in most cases.

SCPI command

*RST ➔ Reset the Keithley commands.

SENS:FUNC "RES" ➔ Sets the measuring method to resistance

SENS:RES:RANG:AUTO ON ➔ Sets the range to auto range SENS:RES:RSEN ON ➔ 4-Wire Measurement

SENS:RES:OCOM ON ➔ VEMF compensation.

OUTP ON ➔ Outputs the resistance data

Sourcing voltage, measuring current, and reading in ohms

This measurement method is useful for high resistance samples.High-resistance materials allow only small currents to flow. Applying a higher voltage ensures you get a measurable current, improving signal-to-noise ratio.

SCPI command

*RST ➔ Reset the Keithley commands.

SENS:FUNC "CURR" ➔ Sets the measuring method to current

SENS:CURR:RANG:AUTO ON ➔ Sets the range to auto range

SENS:CURR:UNIT OHM ➔ Sets the unit to ohm to retrieve resistance from the current.

SENS:CURR:RSEN ON ➔ 4-Wire Measurement

SENS:CURR:OCOM ON ➔ VEMF compensation.

SOUR:FUNC VOLT ➔ Sets the sourcing method to voltage.

SOUR:VOLT …➔ Sets the sourcing voltage (in Volts) SOUR:VOLT:ILIM …➔ Sets the current limit (in Amps) OUTP ON ➔ Outputs the resistance data

Sourcing current, measuring voltage, and reading in ohms

This measurement method is useful for low resistance samples.Low-resistance materials allow more current to pass easily. A higher current ensures accurate resistance measurements without excessive voltage drops.

SCPI command

*RST ➔ Reset the Keithley commands.

SENS:FUNC "VOLT" ➔ Sets the measuring method to voltage

SENS:VOLT:RANGe:AUTO ON ➔ Sets the range to auto range

SENS:VOLT:UNIT OHM ➔ Sets the unit to ohm to retrieve resistance from the current.

SENS:VOLT:RSEN ON ➔ 4-Wire Measurement

SENS:VOLT:OCOM ON ➔ VEMF compensation.

SOUR:FUNCtion CURR ➔ Sets the sourcing method to current.

SOUR:CURRent ...➔ Sets the sourcing current (in Amps)

SOUR:CURRent: …➔ Sets the voltage limit (in Volts)

OUTP ON ➔ Outputs the resistance data

Useful Keithley2450 Commands list

Each of the commands following can be used on the 3 following parameters • Current: CURRent

• Resistance: RESistance

• Voltage: VOLTage

These will replace the <function> part of the command

Measure (MEASure?)

More information is available in “:MEASure?” part of Keithley 2450 – Reference Manual (p.399-401)

This command makes measurements, places them in a reading buffer, and returns the last reading

:MEASure:<function>? performs the same function as sending :SENse:FUNCtion, then READ?.

This means that it will only return 1 value rather than giving the live value. Thus, it is recommended to use the SENSe subsystem instead.

Sense (SENSe)

The SENS subsystem commands configure and control the measurement functions of the instrument. Many of these commands are set for a specific function (current, voltage, or resistance).

SENS:FUNC <function>

More information is available in “[:SENSe[1]]:FUNCtion[:ON]” part of Keithley 2450 – Reference Manual (p.463-464)

This command selects the active measurement function.

:FUNC “VOLT” ➔ It makes the voltage measurement function the active function.

SENS:<function>:RSEN

More information is available in “[:SENSe[1]]:<function>:RSENse” part of Keithley 2450 – Reference Manual (p.455)

This command selects 2-wire or 4-wire measurement method. As explained in the general ECR manual, we use 4-wire measurement to remove the impact of the test lead resistance on the final measurement.

SENS:RES:RSEN OFF ➔ 2-Wire resistance measurement

SENS:RES:RSEN ON ➔ 4-Wire resistance measurement (Recommended)

SENS:<function>:RANG

More information is available in “[:SENSe[1]]:<function>:RANGe[:UPPer]” part of Keithley 2450 – Reference Manual (p.451-452)

This command determines the positive full-scale measure range.

For example:

SENS:CURR:RANG 10E-6 ➔ Select the 10 μA range.

SENS:RES:RANG 2E6 ➔ Select the 2 MΩ range.

Note: SENS :VOLT :RANG … (V) is only useful to suppress the time taken for range selection in automatic mode. Hence, we do not recommend to use it.

SENS:<function>:RANG:AUTO

More information is available in “[:SENSe[1]]:<function>:RANGe:AUTO” part of Keithley 2450 – Reference Manual (p.447)

This command determines if the measurement range is set manually or automatically for the selected measure function.

When automatic measure range is selected, the instrument automatically selects the best range to measure the signal. If the measurement reaches 105 percent of the present range, the instrument changes the measurement range to the next higher range.

SENS:RES:RANG:AUTO ON ➔ Autorange measurement of resistance activated.

AUTORANGE greatly facilitates the setting of the measurement range thus is recommended in most applications.

SENS:<function>:OCOM

More information is available in “[:SENSe[1]]:<function>:OCOMpensated” part of Keithley 2450 – Reference Manual (p.446-447)

This command enables or disables offset compensation.

This feature is only applied to resistance measurements or when [:SENSe[1]]:CURRent:UNIT is set to OHM.

The presence of thermoelectric EMFs (VEMF) can adversely affect low-resistance measurement accuracy. These thermoelectric EMFs appear when there is a difference in temperature between different points. To overcome these offset voltages, you can use offset-compensated ohms if you are making 4-wire resistance measurements on ranges up to 100 kΩ.

For a normal resistance measurement, the Model 2450 sources a current (I) and measures the voltage (V). The resistance (R) is then calculated as (R=V/I) and the reading is displayed.

For offset-compensated ohms, two measurements are performed: one normal resistance measurement, and one using the lowest current source setting.

The offset-compensated ohms reading is then calculated as follows:

𝑂𝑓𝑓𝑠𝑒𝑡−𝐶𝑜𝑚𝑝𝑒𝑛𝑠𝑎𝑡𝑒𝑑(Ω)= (𝑉2 −𝑉1)/(I2-O1)

Where:

V1: Voltage measurement with the current source at its normal level.

V2: Voltage measurement using the lowest current source setting.

I1: Current measurement with the source set to a specific level.

I2: Current measurement with the source set to zero.

This 2-point measurement process and reading calculation eliminates the resistance contributed by the presence of VEMF. When the source is turned on, the output cycles between the programmed value and zero (0 A or 0 V) to derive the offset-compensated ohms measurement. This means that the measurement speed is significantly reduced.

SENS:AZER:ONCE

More information is available in “[:SENSe[1]]:AZERo:ONCE” part of Keithley 2450 – Reference Manual (p.456)

This command causes the instrument to refresh the reference and zero measurements once.

Can be used to bias the resistance given by the Keithley before the measurement.

SOURce subsystem

The commands in the SOURce subsystem configure and control the current source and voltage source.

SOUR:FUNC <function>

More information is available in “:SOURce[1]:FUNCtion[:MODE]” part of Keithley 2450 – Reference Manual (p.476-477)

This command contains the source function, which can be voltage or current.

SOUR:FUNC CURR ➔ Set the source function to be a current source.

SOUR:<function>:RANG

More information is available in “:SOURce[1]:<function>:RANGe”part of Keithley 2450 – Reference Manual (p.479-480)

This command selects the range for the source for the selected source function.

SOUR:<function>:RANG:AUTO

More information is available in “:SOURce[1]:<function>:RANGe:AUTO”part of Keithley 2450 – Reference Manual (p.480)

This command determines if the range is selected manually or automatically for the selected source function.

SOUR:CURR:RANG:AUTO ON ➔ Auto range sourcing of intensity activated.

AUTORANGE greatly facilitates the setting of the sourcing range thus is recommended in most applications.

SOUR:<function>:<x>LIM

More information is available in “:SOURce[1]:<function>:<x>LIMit[:LEVel]”part of Keithley 2450 – Reference Manual (p.475)

This command selects the source limit for measurements of the selected function.

SOUR:CURR:VLIM 15 ➔ Sets the voltage limit to 15V when sourcing current. • SOUR:VOLT:ILIM 0.1 ➔ Sets the intensity limit to 0.1A when sourcing voltage.

This function can be used to protect a DUT from exceeding its dielectric strength or maximum current density.

SOUR:<function>:READ:BACK

More information is available in “:SOURce[1]:<function>:READ:BACK”part of Keithley 2450 – Reference Manual (p.481)

This command determines if the instrument records the measured source value or the configured source value when making a measurement.

When source readback is on, the instrument measures both voltage and current and uses these values in the resistance calculations. When source readback is off, the instrument uses the programmed source value and the measured value in the resistance calculations. Note that the measured source value is more accurate than the programmed source value, so measurements made with source readback on are more but reduce the measurement speed.

SOUR:VOLT:READ:BACK ON ➔ Set the read back on for the voltage source.

SOUR:SWE:<function>:LIN

More information is available in “:SOURce[1]:SWEep:<function>:LINear”part of Keithley 2450 – Reference Manual (p.485-486)

This command sets up a linear sweep for a fixed number of measurement points.

ECR – General Presentation| Rtec-Instruments, Inc. 18

Configuration Window

The window can be divided into 4 parts:

Identification Window:

COM: If the Keithley communicates by a COM Port, will display here the COM Port used.

Address:

…:

Commands Window:

UserID:

ConnectCmds: The commands that will be sent when the software starts. The instrument will return “KEITHLEY INSTRUMENTS, MODEL nnnn, xxxxxxxx, yyyyyy” (nnnn is the model number / xxxxxxxx is the serial number / yyyyyy is the firmware revision level)

CustomCmd(1/2/3/4): To modify the content of the command sent, you need to modify the content of “CustomCmd(1/2/3/4)”.

CC(1/2/3/4)Display: To modify the name that appears during the recipe creation, you need to modify the content of “CC(1/2/3/4)Display”.

StatusCmd:

IsTCP: This command needs to be set to “True” if the Keithley is communicating with the PC through a LAN interface (Part 2.2.2).
Otherwise, can be set to “False”

Commands Update:

Write and Read: If you enter a command on a line of the “Write” Column, by pressing “Write”, then “Read”, the line in the “Read” column will be automatically updated.

Commands Control:

UPDATE STATUS: The commands retrieve live data from the Keithley (Voltage, Resistance and Temperature). The temperature may not work properly.

CUSTOM CMD (1/2/3/4): This prepares the specific custom command that is entered in the field on the left. By clicking on “Send command”, the command will be activated

RESET: Writes a *RST command that resets the instrument settings to their default values and clears the reading buffers.

SEND: Sends the command that has been written in the free field above the button

SEND COMMAND: Sends the custom command that has been selected previously.

Making resistance measurements

Measure resistance using resistance function

This is the easiest method to measure resistance of the device under test and can be used in most cases.

Sourcing voltage, measuring current, and reading in ohms

Sourcing current, measuring voltage, and reading in ohms

Useful Common Command Explanation

To create a new command, please note the following rules:

Commands execute in the order that they are presented in the command message.

You should set the measure function first, then set the source function, because setting the measure function may change the source function.

When setting a range, you should first set the limit to a value higher than the measure range you intend to set.

⚠️

Valid commands that precede an invalid command in a command message are executed. Valid commands that follow an invalid command in a command message are ignored.

Measuring and sourcing methods by sample type:

For most samples: Set the measure function to resistance. When the measure function is set to resistance, the instrument sets the source current and source values automatically.

For high resistance samples: Source voltage, measure current, and set measure units to ohms

For low resistance samples: Source current, measure voltage, and set measure units to ohms

List of SCPI command with X for:

-RES : Resistance

CURR : Current

VOLT: Voltage

Each of the commands following can be used on the 3 parameters above.

*RST

Reset the Keithley commands

Measuring function

SENS:AZER:ONCE

More information is available in “[:SENSe[1]]:AZERo:ONCE” part of Keithley 2450 – Reference Manual (p.456)

This command causes the instrument to refresh the reference and zero measurements once.

Can be used to bias the resistance given by the Keithley before the measurement.

SENS:FUNC "X"

:FUNC “VOLT” ➔ It makes the voltage measurement function the active function.

Sets the measuring method.

SENS:X:RANG: …

This command determines the positive full-scale measure range.

For example:

SENS:CURR:RANG 10E-6 ➔ Select the 10 μA range.

SENS:RES:RANG 2E6 ➔ Select the 2 MΩ range.

Note: SENS :VOLT :RANG … (V) is only useful to suppress the time taken for range selection in automatic mode. Hence, we do not recommend to use it.

SENS:X:RANG:AUTO ON

This command determines if the measurement range is set manually or automatically for the selected measure function.

SENS:RES:RANG:AUTO ON ➔ Autorange measurement of resistance activated.

AUTORANGE greatly facilitates the setting of the measurement range thus is recommended in most applications.

Sets the measurement range to a full scale or auto range.

SENS:X:UNIT OHM

Sets the unit to ohm to retrieve resistance from the measuring method.

SENS:X:OCOM ON

This command enables or disables offset compensation.

This feature is only applied to resistance measurements or when [:SENSe[1]]:CURRent:UNIT is set to OHM.

For a normal resistance measurement, the Model 2450 sources a current (I) and measures the voltage (V). The resistance (R) is then calculated as (R=V/I) and the reading is displayed.

For offset-compensated ohms, two measurements are performed: one normal resistance measurement, and one using the lowest current source setting.

The offset-compensated ohms reading is then calculated as follows:

𝑂𝑓𝑓𝑠𝑒𝑡−𝐶𝑜𝑚𝑝𝑒𝑛𝑠𝑎𝑡𝑒𝑑(Ω)= (𝑉2 −𝑉1)/(I2-O1)

Where:

V1: Voltage measurement with the current source at its normal level.

V2: Voltage measurement using the lowest current source setting.

I1: Current measurement with the source set to a specific level.

I2: Current measurement with the source set to zero.

VEMF compensation for each measuring method.

SENS:X:RSEN OFF

This command selects 2-wire or 4-wire measurement method. As explained in the general ECR manual, we use 4-wire measurement to remove the impact of the test lead resistance on the final measurement.

Measurement for each measuring method.

OFF= 2-Wire

ON= 4-Wire (recommended)

Sourcing function

SOUR:FUNC X

More information is available in “:SOURce[1]:FUNCtion[:MODE]” part of Keithley 2450 – Reference Manual (p.476-477)

This command contains the source function, which can be voltage or current.

SOUR:FUNC CURR ➔ Set the source function to be a current source.

Sets the sourcing method

SOUR:CURR:ILIM …

SOUR:VOLT:ILIM 0.1 ➔ Sets the intensity limit to 0.1A when sourcing voltage.

SOUR:VOLT:VLIM …

Sets the volt/current limit based on the sourcing method.

SOUR:CURR:VLIM 15 ➔ Sets the voltage limit to 15V when sourcing current.

This function can be used to protect a DUT from exceeding its dielectric strength or maximum current density.

SOUR:X:RANG:AUTO

This command determines if the range is selected manually or automatically for the selected source function.

SOUR:CURR:RANG:AUTO ON ➔ Auto range sourcing of intensity activated.

SOUR:X:RANG

This command selects the range for the source to a full-scale or auto range.

SOUR:X:READ:BACK

More information is available in “:SOURce[1]:<function>:READ:BACK”part of Keithley 2450 – Reference Manual (p.481)

This command determines if the instrument records the measured source value or the configured source value when making a measurement.

SOUR:VOLT:READ:BACK ON ➔ Set the read back on for the voltage source.

This command determines if the instrument records the measured source value or the configured source value when making a measurement

SOUR:SWE:X:LIN

This command sets up a linear sweep for a fixed number of measurement points.

OUTP ON

Outputs the resistance data

The command words are separated by colons (:). A proper command must have the letters in caps. The others are optional.

Example: “SYSTem:COMMunication:LAN:CONFigure AUTO”. This equals to “SYST:COMM:LAN:CONF AUTO”. It starts from the general parameter (the system) to the more specific one (configuration).

More Keithley2450 Commands list

Each of the commands following can be used on the 3 following parameters • Current: CURRent

• Resistance: RESistance

• Voltage: VOLTage

These will replace the <function> part of the command

Measure (MEASure?)

More information is available in “:MEASure?” part of Keithley 2450 – Reference Manual (p.399-401)

This command makes measurements, places them in a reading buffer, and returns the last reading

:MEASure:<function>? performs the same function as sending :SENse:FUNCtion, then READ?.

This means that it will only return 1 value rather than giving the live value. Thus, it is recommended to use the SENSe subsystem instead.

Sense (SENSe)

The SENS subsystem commands configure and control the measurement functions of the instrument. Many of these commands are set for a specific function (current, voltage, or resistance).

Annex

Keithley 2450 – Reference Manual.pdf

41.7 MiB

MFT Software operations necessary to perform the measurement are described and explained in the software guide specific to this module.

Keithley 2450 - Internal Manual - 2024-AS-01A-EN

General Presentation

First installation : Setting Up Communication

USB or Ethernet

Setting Up Ethernet Communication (LAN)

Setting Up the Keithley

Lan Tab setting

Ensuring Static IP Address Is Set

On the PC

Setting Up USB Communication

Keithley I/O Layer software download:

Setting Up the Keithley

Wizard Configurator

Plug the Measurement Cable

Enabling Keithley Control in MFT and Adding Commands to Your Recipe

Verify the communication with the Keithley2450

Go to your testing recipe

Advanced ECR Measurement

Advanced ECR Command control

Introduction

Making resistance measurements

Resistance Measurement Methods

Measure resistance using resistance function

SCPI command

Sourcing voltage, measuring current, and reading in ohms

SCPI command

Sourcing current, measuring voltage, and reading in ohms

SCPI command

Useful Keithley2450 Commands list

Measure (MEASure?)

Sense (SENSe)

SENS:FUNC <function>

SENS:<function>:RSEN

SENS:<function>:RANG

SENS:<function>:RANG:AUTO

SENS:<function>:OCOM

SENS:AZER:ONCE

SOURce subsystem

SOUR:FUNC <function>

SOUR:<function>:RANG

SOUR:<function>:RANG:AUTO

SOUR:<function>:<x>LIM

SOUR:<function>:READ:BACK

SOUR:SWE:<function>:LIN

Configuration Window

The window can be divided into 4 parts:

Making resistance measurements

Measure resistance using resistance function

Sourcing voltage, measuring current, and reading in ohms

Sourcing current, measuring voltage, and reading in ohms

Useful Common Command Explanation

Measuring and sourcing methods by sample type:

List of SCPI command with X for:

*RST

Measuring function

SENS:AZER:ONCE

SENS:FUNC "X"

SENS:X:RANG: …

SENS:X:RANG:AUTO ON

SENS:X:UNIT OHM

SENS:X:OCOM ON

SENS:X:RSEN OFF

Sourcing function

SOUR:FUNC X

SOUR:CURR:ILIM …

SOUR:VOLT:VLIM …

SOUR:X:RANG:AUTO

SOUR:X:RANG

SOUR:X:READ:BACK

SOUR:SWE:X:LIN

OUTP ON

More Keithley2450 Commands list

Measure (MEASure?)

Sense (SENSe)

Annex