https://circuit.quest/categories/digital/ Recent content in Digital on Circuit Quest Hugo en-us Sun, 05 Apr 2026 00:00:00 +0530 https://circuit.quest/articles/antenna-diode/ Sun, 05 Apr 2026 00:00:00 +0530 https://circuit.quest/articles/antenna-diode/ <h2 id="what-is-an-antenna-diode">What Is an Antenna Diode?</h2> <p>An <strong>antenna diode</strong> is a protection diode placed in a digital integrated circuit to guard transistor gates against damage during the chip fabrication process. It has nothing to do with radio antennas. The name comes from the &ldquo;antenna effect,&rdquo; a phenomenon that occurs during plasma etching.</p> <h2 id="the-antenna-effect">The Antenna Effect</h2> <p>Modern ICs are built layer by layer. Metal interconnects and polysilicon wires are patterned using <strong>plasma etching</strong>, a process where ionized gas (plasma) selectively removes material. During this process, conductive structures like metal wires and polysilicon lines collect charge from the plasma.</p>