FET: Diode If-Vf Test

Measures the forward bias voltage vs. current characteristics of the body (free-wheeling) diode. SMU voltage pulse is used for the forward bias output.

Used with:

  • B1506A: FET DUT

  • B1505A: FET DUT, IV test type
Set the test parameters based on the specifications in the device's data sheet:
- If the data sheet lists a maximum test limit for a parameter, use that value.
- If there is no maximum test limit, use a typical value.

See also Setting IV and CV Test Parameters.

Test Schematic

Gate Parameters

Gate: The SMU connected to Gate terminal, primary sweep voltage output. Select Gate SMU from the drop-down menu.

VgStart (V): The Sweep start voltage for Gate terminal. Some devices require a negative VgStart voltage. Check the device data sheet.

VgStop (V): The Sweep stop voltage for Gate terminal. Some devices require a negative VgStop voltage. Check the device data sheet.

VgStep (V): The Sweep step voltage for Gate terminal. Some devices require a negative VgStep voltage. Check the device data sheet.

Source: The GNDU:GND connected to Source terminal. This field cannot be changed.

Drain Parameters

Drain: The SMU connected to Drain terminal, secondary sweep voltage output. For the B1506A-H21, select Input SMU, for the B1506A-H51 and -H71, select the Input UHCU.

VdStart (V): The DC bias sweep start voltage. Some devices require a negative VdStart voltage. Check the device data sheet.

VdStop (V): The DC bias sweep stop voltage. Some devices require a negative VdStop voltage. Check the device data sheet.

VdLinearStep (V): The DC bias sweep step voltage, effective if Scale = LINEAR. Some devices require a negative Step voltage. Check the device data sheet.

IdLimit (A): The Drain current compliance. If the VdStart voltage is negative, set IdLimit negative also.

PdLimit (W): The Drain power compliance.

PulsePeriodMode: The Pulse period mode, AUTO or MANUAL. (If you choose MANUAL, you must also set the ManualPulsePeriod parameter.)

ManualPulsePeriod (s): The Pulse period. Use this parameter only when you have selected PulsePeriodMode = MANUAL.

PulseWidth (s): The Pulse width.