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

Germanium fraction x

Required number.

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

Compute relaxed SiGe lattice mismatch relative to silicon using Vegard's law with aGe = 5.658 angstrom and aSi = 5.431 angstrom. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Lattice mismatch fraction

Returned number.

• Material composition, geometry, process history, temperature, electric field, bias, interfaces, parasitics, and fitted parameter ranges can invalidate a compact semiconductor model.
• Germanium fraction x must be at least 0.
• Germanium fraction x must be no greater than 1.
• 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.

• Pseudomorphic SiGe Strain Calculator

  Compute in-plane compressive strain of a fully pseudomorphic SiGe layer on silicon relative to the relaxed SiGe lattice constant from Vegard's law.

• Impact Ionization Coefficient Calculator

  Compute the silicon impact ionization coefficient from the electric field using the Chynoweth law.

• InP Lattice Constant Calculator

  Compute the InP lattice constant at a temperature using the 25 degrees Celsius reference value 5.869 angstrom and a documented thermal expansion coefficient of 4.56e-6 per kelvin.