If two nets of the same layer and length, but one has double width, which has more delay and why?

Q: "If two nets of the same layer and length, but one has double width, which has more delay and why?"

"The net with double width will generally have less delay.\nReasoning (RC Delay): Wire delay is primarily determined by the product of its resistance (R) and capacitance (C).\nResistance (R): Resistance is inversely proportional to the cross-sectional area of the wire. For a fixed thickness (T), resistance is inversely proportional to width (W). R ∝ 1 / (W * T). Doubling the width (W -\u0026gt; 2W) approximately halves the resistance (R -\u0026gt; R/2).\n"

The net with double width will generally have less delay.

Reasoning (RC Delay): Wire delay is primarily determined by the product of its resistance (R) and capacitance (C).

Resistance (R): Resistance is inversely proportional to the cross-sectional area of the wire. For a fixed thickness (T), resistance is inversely proportional to width (W). R ∝ 1 / (W * T). Doubling the width (W -> 2W) approximately halves the resistance (R -> R/2).

Capacitance (C): Capacitance has components to ground/substrate (Area Capacitance, Fringe Capacitance) and coupling capacitance to neighbors.

Ground Capacitance: Roughly proportional to width (W). Doubling width (W -> 2W) might almost double this component.

Coupling Capacitance: it can be lateral and vertical coupling. Vertical coupling increases with width and lateral coupling depends on thickness.

Scaling Impact: https://www.vlsisystemdesign.com/kunal58625/php/scaling.php

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