Use this semiconductor calculation for first-order device, material, fabrication, interconnect, packaging, or reliability estimates when every coefficient and unit convention is known.

VSB (V)

Required number in V. Source-to-body voltage.

Gamma (V^0.5)

Required number in V^0.5. Body-effect coefficient.

phi F (V)

Required number in V. Fermi potential magnitude; the formula uses 2 phi F.

VT0 (V)

Optional number in V. Zero-bias threshold voltage.

The cited overview of MOSFET supplies background for the terminology and domain context used by this tool.^[1]

Compute threshold voltage with source-body reverse bias applied. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

VT (V)

Returned number in V.

• Material composition, geometry, process history, temperature, electric field, bias, interfaces, parasitics, and fitted parameter ranges can invalidate a compact semiconductor model.
• VSB must be at least 0.
• Gamma must be at least 0.
• phi F must be at least 5e-324.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

Compare the estimate with measured process data, current device documentation, and a higher-fidelity circuit, field, thermal, quantum, or TCAD model when the decision requires it.

• MOSFET Body-Effect Shift Calculator

  Compute the MOSFET threshold-voltage shift caused by source-body reverse bias.

• BJT Punch-Through Voltage Calculator

  Compute the total collector-base junction potential required for the depletion region to span a uniformly doped neutral base: Vtotal=q·NB·WB²/(2·εSi). This is not the externally applied reverse bias; subtract the junction built-in potential to estimate that bias.

• Floating Body Kink Shift Calculator

  Estimate the floating-body kink threshold-voltage shift from the excess drain bias beyond saturation.