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

Reverse bias (V)

Required number in V. Applied reverse-bias voltage magnitude. Must be at least 0 V and strictly below breakdown; 0 yields M=1. Signed values not supported.

Breakdown voltage (V)

Required number in V. Breakdown voltage magnitude at the operating conditions. Must be greater than 0 V; denominator for V/Vb.

Exponent N

Optional number. Ionization exponent N in the Miller model. Must be in [1, 6]; default 2.

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

Compute the avalanche photodiode multiplication factor from the Miller model M=1/[1-(V/Vb)^N]. Inputs are magnitudes: reverse-bias magnitude V≥0 V must remain below breakdown magnitude Vb>0 V (numerator V, denominator Vb; V=0 gives M=1, V→Vb- diverges). Exponent N in [1, 6] (default 2) captures the ionization coefficients. Signed voltages are not supported (use magnitudes). Result M≥1 is a dimensionless factor (per-carrier gain, not total current). Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Multiplication factor

Returned number. Avalanche multiplication factor M≥1 (dimensionless gain per primary carrier).

• Material composition, geometry, process history, temperature, electric field, bias, interfaces, parasitics, and fitted parameter ranges can invalidate a compact semiconductor model.
• Reverse bias must be at least 0.
• Breakdown voltage must be at least 5e-324.
• Exponent N must be at least 1.
• Exponent N must be no greater than 6.
• 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.

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