Deep Trench Capacitor in Three Dimensional Through Silicon via Keepout Area for Electrostatic Discharge Protection

To fully enable and leverage the power of advanced processors, products must have abundant cache memory with much shorter access paths without increasing chip size. This requires growing products in the z-direction by building stacked chips (3-D chips). To optimize 3-D product costs, the area consumed by other processing requirements such as electrostatic discharge (ESD) protection needs to be as efficient as possible. Placing ESD structures made with deep trench capacitors in 3-D through silicon via keepout areas optimizes silicon area since these structures enable placement of ESD devices in space that would otherwise not be used.