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Section 6: Measure I-V characteristics of FETs 

Model 2470 High Voltage SourceMeter Instrument User's Manual 

 

6-2

2470-900-01 Rev. A / 

May

 2019 

The SCPI and TSP examples differ in this application. The TSP version uses Keithley Instruments 

TSP-Link

®

, which is a high-speed trigger synchronization and communication bus that test system 

builders can use to connect multiple instruments in a master and subordinate configuration. Once 

connected, all the instruments that are equipped with TSP-Link in a system can be programmed and 

operated under the control of the master instrument or instruments. This allows the instruments to 

run tests more quickly because they can be decoupled from frequent computer interaction. TSP-Link 

is not available when the SCPI command set is selected. 

Equipment required 

Two 2470 High Voltage SourceMeter Instruments

Four TRX-1100V-

X

 3-Slot High-Voltage Low-Noise Triaxial Cables (available from Keithley

Instruments)

A metal-shielded test fixture or probe station with female triaxial connectors

One high power or wide band-gap three-terminal FET

One ethernet, GPIB, or USB cable for the TSP remote command examples

One cross-over ethernet cable for TSP-Link connections between the two 2470s (one is included

with each 2470)

Set up remote communications 

This application is configured to run remotely. You can run this application from any of the supported 

communication interfaces for the instrument (GPIB, USB, or ethernet). 

The following figure shows the rear-panel connection locations for the remote communication 

interfaces.   

Figure 28: Model 2470 remote interface connections 

Summary of Contents for SourceMeter 2470

Page 1: ...User s Manual 2470 900 01 Rev A May 2019 P2470 900 01A 2470 900 01A tek com keithley Model 2470 High Voltage SourceMeter Instrument...

Page 2: ...High Voltage SourceMeter Instrument User s Manual Model 2470...

Page 3: ...tructions in English TSP TSP Link and TSP Net are trademarks of Keithley Instruments LLC All Keithley Instruments product names are trademarks or registered trademarks of Keithley Instruments LLC Othe...

Page 4: ...d to mains These instruments will be marked as category II or higher Unless explicitly allowed in the specifications operating manual and instrument labels do not connect any instrument to mains Exerc...

Page 5: ...lains hazards that could damage the instrument Such damage may invalidate the warranty The CAUTION heading with the symbol in the user documentation explains hazards that could result in moderate or m...

Page 6: ......

Page 7: ...terface 3 1 Remote communications interfaces 3 1 Supported remote interfaces 3 1 GPIB communications 3 2 Install the GPIB driver software 3 2 Install the GPIB cards in your computer 3 2 Connect GPIB c...

Page 8: ...ents on the front panel graph 5 11 Set up the application using SCPI commands 5 12 Set up the application using TSP commands 5 13 Measure I V characteristics of FETs 6 1 Introduction 6 1 Equipment req...

Page 9: ...do I upgrade the firmware 7 2 Why can t the 2470 read my USB flash drive 7 2 How do I change the command set 7 3 Why am I getting a 5074 event code 7 4 How do I save the present state of the instrumen...

Page 10: ...imilar products on the market With its 1100 V and 10 fA capability the 2470 is optimized for characterizing and testing high voltage low leakage devices materials and modules such as silicon carbide S...

Page 11: ...are available on new and existing products Contact your local Keithley Instruments office sales partner or distributor for details Contact information If you have any questions after you review the in...

Page 12: ...to perform tests from the front panel and over a remote interface These applications are presented after the summary information about the 2470 The applications include Making basic front panel measur...

Page 13: ...on an incorrect line voltage may cause damage to the instrument possibly voiding the warranty The power cord supplied with the 2470 contains a separate protective earth safety ground wire for use with...

Page 14: ...t the male end of the power cord to a grounded AC outlet Figure 1 Model 2470 AC receptacle on rear panel To turn a 2470 on or off 1 Before turning the instrument on disconnect any devices under test D...

Page 15: ...esolution or speed HELP key Opens help for the area or item that is selected on the display If there is no selection when you press the HELP key it displays overview information for the screen you are...

Page 16: ...rea network LAN 1588 LED indicator Illuminates when the instrument is connected to an IEEE 1588 compliant device Note that 1588 functionality is not supported at this time This functionality will be m...

Page 17: ...powered off if a hardware or software fault occurs When the source of the instrument is turned off it may not completely isolate the instrument from the external circuit You can use the Output Off set...

Page 18: ...s or pencils to touch the touchscreen It is strongly recommended that you use only fingers to operate the instrument Use of clean room gloves to operate the touchscreen is supported Select items on th...

Page 19: ...Swipe screens maximized and minimized Screen element Description 1 Minimize indicator You can swipe down to minimize the swipe screens 2 Swipe screen indicator Each circle represents one swipe screen...

Page 20: ...d the value shown is the programmed source value If the output is off the displayed source value is replaced with Output Off The icon on the right side of the swipe screen heading bar is a shortcut to...

Page 21: ...reading buffer Figure 7 STATISTICS swipe screen USER swipe screen If you program custom text it is displayed on the USER swipe screen For example you can program the 2470 to show that a test is in pro...

Page 22: ...on in a submenu opens an interactive screen Store measurements on a USB flash drive If there is measurement data in the buffer you can copy it from the 2470 to a USB flash drive The information is sav...

Page 23: ...n capture of the front panel display to a graphic file The instrument saves the graphic file to the USB flash drive in the PNG file format To save a screen capture 1 Insert a USB flash drive in the US...

Page 24: ......

Page 25: ...he interface depending on the access mode The 2470 automatically detects the type of communications interface LAN USB or GPIB when you connect to the respective port on the rear panel of the instrumen...

Page 26: ...Install the GPIB driver software Check the documentation for your GPIB controller for information about where to acquire drivers Keithley Instruments also recommends that you check the website of the...

Page 27: ...amage stack no more than three connectors on any one instrument To minimize interference caused by electromagnetic radiation use only shielded GPIB cables Contact Keithley Instruments for shielded cab...

Page 28: ...IB tab 4 Set the GPIB Address 5 Select OK You can also set the GPIB address using remote commands Set the GPIB address with the SCPI command SYSTem GPIB ADDRess or the TSP command gpib address LAN com...

Page 29: ...System select Communication The SYSTEM COMMUNICATIONS window opens 3 Select LAN to see the settings for that interface Set up automatic LAN configuration If you are connecting to a LAN that has a DHCP...

Page 30: ...Gateway address 7 Enter the Subnet mask 8 Select Apply Settings to save your settings Set up LAN communications on the computer This section describes how to set up the LAN communications on your com...

Page 31: ...te lxistandard org USB communications To use the rear panel USB port you must have the Virtual Instrument Software Architecture VISA layer on the host computer See How to install the Keithley I O Laye...

Page 32: ...e Can Windows connect to Windows Update to search for software dialog box opens select No and then select Next 5 On the USB Test and Measurement device dialog box select Next and then select Finish Co...

Page 33: ...eithley Configuration Panel to determine the VISA resource string 1 Click Start Keithley Instruments Keithley Configuration Panel The Select Operation dialog box is displayed Figure 13 Select Operatio...

Page 34: ...nstrument Driver dialog box is displayed Figure 15 Select Instrument Driver dialog box 6 Select Auto detect Instrument Driver Model 7 Click Next The Configure USB Instrument dialog box is displayed wi...

Page 35: ...eithley Configuration Panel select File Save Verify the instrument through the Keithley Communicator 1 Click Start Keithley Instruments Keithley Communicator 2 Select File Open Instrument to open the...

Page 36: ...ge resides in the firmware of the instrument Changes you make through the web interface are immediately made in the instrument When the LAN and instrument establish a connection you can open the web p...

Page 37: ...re used the configuration information for the correct ethernet card The network card of the computer is enabled The IP address of the instrument is compatible with the IP address on the computer The s...

Page 38: ...history link opens the LXI Home page The ID button which allows you to identify the instrument Refer to Identify the instrument on page 3 14 Identify the instrument If you have a bank of instruments y...

Page 39: ...2470 with command sets that are based on the SCPI or Test Script Processor TSP programming languages You can change the command set that you use with the 2470 The remote command sets that are availab...

Page 40: ...Rev A May 2019 To verify which command set is selected from a remote interface Send the command LANG To change to the SCPI command set from a remote interface Send the command LANG SCPI Reboot the ins...

Page 41: ...make measurements on a 10 k resistor by sourcing voltage and measuring current You can make similar measurements on any two terminal device under test DUT if appropriate source values are used Some o...

Page 42: ...t that is provided with the 2470 the Keithley Instruments Model 8608 High Performance Clip Lead Set One 10 k resistor to test Device connections Turn the power to the instrument off before attaching c...

Page 43: ...trument or cycle power if the instrument is already on 2 On the front panel press the FUNCTION key to verify the source and measure function 3 Under Source Voltage and Measure select Current 4 Select...

Page 44: ......

Page 45: ...This soak period allows time for the device to charge so that you can make a settled current measurement In this application the resulting current is measured the entire time the device is biased In...

Page 46: ...USB or ethernet The following figure shows the rear panel connection locations for the remote communication interfaces For additional information about setting up remote communications see Remote comm...

Page 47: ...ction schematics The following figures show the rear terminal connections to the device under test DUT for these applications If capacitor leakage measurements are noisy you may need to use the high c...

Page 48: ...s test you will Reset the instrument Set the instrument to read the rear terminals Select the source voltage function and measure current function Set the magnitude of the voltage source Turn on autor...

Page 49: ...ment to use the rear panel terminals R is displayed to the left of the switch 4 Press the HOME key 5 Press the FUNCTION key 6 Under Source Voltage and Measure select Current 7 Select the button next t...

Page 50: ...view the leakage current measurements on the front panel graph 1 Press the MENU key 2 Under Views select Graph 3 Select the Scale tab 4 Under Y Axis next to Scale Format select Log 5 Under X Axis nex...

Page 51: ...the source voltage to 300 V Set the current limit to 10 mA Set the instrument to measure current Set to use rear panel terminals Set the current range to autorange Set the number of power line cycles...

Page 52: ...f Test Script Builder From the Instrument Console you can copy the data into a spreadsheet for graphing Send the following commands for this example application Reset the instrument which also clears...

Page 53: ...erface using the SCPI command set and the remote interface using the Test Script Processor TSP command set You typically make insulation resistance measurements between traces on a printed circuit boa...

Page 54: ...to set the instrument to use the rear panel terminals R is displayed to the left of the switch 4 Press the HOME key 5 Press the FUNCTION key 6 Under Source Voltage and Measure select Resistance 7 Sel...

Page 55: ...e 2470 900 01 Rev A May 2019 5 11 Viewing the measurements on the front panel graph To view the insulation resistance measurements on the front panel graph 1 Press the MENU key 2 Under Views select Gr...

Page 56: ...ROUT TERM REAR SOUR FUNC VOLT SOUR VOLT 700 SOUR VOLT ILIM 0 01 SENS FUNC CURR SENS CURR RANG AUTO ON SENSE CURR UNIT OHM TRIG LOAD SimpleLoop 10 0 1 OUTP ON INIT WAI TRAC DATA 1 10 defbuffer1 READ R...

Page 57: ...help for TSB and in the Introduction to TSP operation section of the Model 2470 Reference Manual By default the 2470 uses the SCPI command set You must select the TSP command set before sending TSP co...

Page 58: ...e unit smu UNIT_OHM smu terminals smu TERMINALS_REAR smu measure autorange smu ON smu measure nplc 1 Turn on the source output and make readings trigger model load SimpleLoop 10 0 1 smu source output...

Page 59: ...T or gallium nitride GaN or silicon carbide SiC based This application consists of examples that demonstrate How to use a 2470 to perform a drain leakage current measurement on a FET How to use two 24...

Page 60: ...interaction TSP Link is not available when the SCPI command set is selected Equipment required Two 2470 High Voltage SourceMeter Instruments Four TRX 1100V X 3 Slot High Voltage Low Noise Triaxial Cab...

Page 61: ...cable between the digital I O connectors on the back of each of the instruments as shown in the figure below For more detailed information about the digital I O connector pins see Digital I O in the...

Page 62: ...hub Connections for the TSP command set If you use the Test Script Processor TSP command set for remote programming use a RJ 45 LAN crossover cable to connect the TSP Link ports on the rear panels of...

Page 63: ...typically involve measuring very low currents it is recommended that you use the triaxial connections on the rear panel of the 2470 with low noise triaxial cables Triaxial cables provide the lowest no...

Page 64: ...Instrument User s Manual 6 6 2470 900 01 Rev A May 2019 Figure 31 Drain leakage current measurement device connections The following figure shows the connections from the rear panel terminals of the...

Page 65: ...t connections Both 2470s are configured to source voltage and measure current In this circuit Connect the Force HI terminal of 2470 1 to the gate of the FET Connect the Force HI terminal of 2470 2 to...

Page 66: ...s for operation in your programming environment Set up the application using SCPI commands with the trigger model In this application the gate voltage steps from 2 V to 5 V in 1 V steps the drain volt...

Page 67: ...ine 2 to trigger in Set the stimulus for digital line 1 to the notify1 event Clear digital line 2 Set to detect rising edge on line 2 Pseudocode for i 2 to 5 do Set up a for loop from 2 to 5 SMU 1 SOU...

Page 68: ...r i 0 5 0 1 do Set up a for loop from 0 to 5 in 0 1 steps inclusive SMU 2 SOUR VOLT i SOUR CONF LIST STORE sweepVals Set the voltage level to the iteration number Store the source configuration to swe...

Page 69: ...1 V steps the drain voltage sweeps from 0 V to 5 V in 51 steps and the drain current is measured The application retrieves each of 51 readings and source values from defbuffer1 and saves them in the...

Page 70: ...oltage values Create an empty array to hold measured current values Set up a for loop from 2 to 5 inclusive SMU 1 SOUR VOLT i Set the source level to the iteration number of the loop Pseudocode delay...

Page 71: ...anual By default the 2470 uses the SCPI command set You must select the TSP command set before sending TSP commands to the instrument To enable TSP commands 1 Press the MENU key 2 Under System select...

Page 72: ...unc smu FUNC_DC_CURRENT smu measure terminals smu TERMINALS_REAR smu measure autorange smu ON smu measure nplc 1 Turn on the output and initiate readings trigger model load DurationLoop 60 0 2 trigger...

Page 73: ...pplication Settings and TSP Link setup local gateVstart 0 local gateVstop 5 local gateStepSize 0 1 local gateIlimit 0 1 local drainV 10 local drainIlimit 0 1 Fit settings The slope is calculated betwe...

Page 74: ...rigger BLOCK_SOURCE_OUTPUT gate smu OFF 2470 SMU 2 drain setup Set up the source function drain smu source func drain smu FUNC_DC_VOLTAGE drain smu source ilimit level drainIlimit drain smu source lev...

Page 75: ...teLowV gateV fitLowIndex i end end Find drain current and natural log of current at the two fit voltages local drainHighI drain defbuffer1 readings fitHighIndex local drainLowI drain defbuffer1 readin...

Page 76: ...ateStepSize 1 local gateIlimit 1e 3 local drainVstart 0 local drainVstop 5 local drainStepSize 0 1 local drainIlimit 1e 3 Reset the instruments and the TSP Link connection and clear the buffers tsplin...

Page 77: ...unction drain smu measure func drain smu FUNC_DC_CURRENT drain smu measure autorange drain smu OFF drain smu measure terminals drain smu TERMINALS_REAR drain smu measure range drainIlimit Set up TSP L...

Page 78: ...f defbuffer1 n 0 then print nNo readings in buffer n else print string format drainV tdrainI 1 t tdrainV tdrainI 2 t tdrainV tdrai nI 3 t tdrainV tdrainI 4 for k 1 sweepPoints do print string format f...

Page 79: ...he 2470 For additional FAQs see Frequently Asked Questions FAQs in the 2470 Reference Manual Where can I find updated drivers For the latest drivers and additional support information see the Keithley...

Page 80: ...ut and output terminals that are attached to the instrument 4 Turn the instrument power off Wait a few seconds 5 Turn the instrument power on 6 Insert the flash drive into the USB port on the front pa...

Page 81: ...se it to combine commands into scripts If you change the command set reboot the instrument You cannot combine the command sets As delivered from Keithley Instruments the 2470 is set to work with the S...

Page 82: ...or to hazardous voltages that could result in personal injury or death If the safety interlock is not asserted and the source is turned on the following actions occur The nominal output is limited to...

Page 83: ...settings that you want to save To save the setup send the command createconfigscript setupName Where setupName is the name of the setup script that is created Why did my settings change Many of the co...

Page 84: ...n As you increase resolution you decrease the reading speed These settings take effect the next time the output is turned on and measurements are made The Quick Setups allow you to set the instrument...

Page 85: ...nal information about the instrument From the website you can access The Knowledge Center which contains the following handbooks The Low Level Measurements Handbook Precision DC Current Voltage and Re...

Page 86: ...e names are the property of Keithley Instruments All other trademarks and trade names are the property of their respective companies Keithley Instruments Corporate Headquarters 28775 Aurora Road Cleve...

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