Probe Station: I-V Curves with Keithley 2400 and Python Script

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Basic procedure for acquiring I-V Curves on the Probe station, using a Python script and the Keithley 2400 SMU. You will have to connect and land the probes yourself, based on prior training with a probe station.

  1. Connect the Probes & Equipment
    1. Turn on the Keithley 2400 Source-Measure Unit
    2. Connect the positive and negative probes to the Keithley's Input/Output ports, using provided banana plugs.
Banana plug connections to the Keithley 2400 SMU
Banana plug connections to the Keithley 2400 SMU's "Input/Output" ports.
  1. Test your connections - use the Keithley in manual mode to measure resistance or apply a current, and ensure you have a good electrical connection to your wafer/electrodes.
  2. Launch the Python "Spyder" Development Evnironment
    1. Icon on desktop, or `Start > Spyder (Python 3.7)`, or `Start > Anaconda Navigator > Spyder Launch`
    2. Launch once only, the computer is slow and it can take a few seconds for it to start launching.
Python Spyder 3.7 (anacoda) icon.png
  1. `File > Open` : Desktop / Keithley I-V Sweep v3 .py
    1. Python Keithley I-V Sweep v3 icon.png
    2. Save this file into your Desktop / User Data / <<My Group Name>> folder with `File > Save As...`
    3. This determines where the I-V Sweep data will be saved
    4. If you already have a script saved in your folder, then open that script instead of the one on the Desktop
  2. Adjust sweep parameters & save file name
    1. Enable savings files & creating sub-directories ("True" or "False")
    2. Change the filenames to save to. By default, will save in the same folder the script is run from.
    3. Change the Voltage start/stop
    4. Set "Current Compliance", which is the current limit - to prevent device damage.
Screenshot of `Keithley I-V` User-settings
Screenshot of `Keithley I-V` User-settings
  1. Click the Run button to run the script, or choose the menu item `Run > Run`.
    1. Python Spyder - Run Button.png
    2. The Keithley will run through the sweep, and display measurements during the sweep.
    3. The data and plots will be optionally saved into the same folder the script file resides in.
  2. Change devices or sweep paramters and re-run as needed
  3. Shutdown:
    1. Lift probes to safe position <--- IMPORTANT
    2. Turn off Keithley SMU
    3. Close Python