Esd protection using low leakage zener diodes formed with microwave radiation

Abstract

Semiconductor devices and methods for making such devices are described. These devices contain a semiconductor substrate with a first portion containing an integrated circuit device connected to a gate pad in an upper portion of the substrate and a second portion containing a Zener diode having a ESD rating up to about 10000 Volts, where the Zener diode is located around the periphery of the substrate. MW radiation can be used to form a single crystal Si material in a trench of the Zener diode 20, reducing the grain boundaries per unit area of the Zener diode by growing (or re-growing) the Si grains to a larger size while consuming the smaller grains. Thus, the leakage current from the Zener diode does not increase when the cross-sectional area of the Zener diode is increased from just surrounding the gate pad to encompass more of the substrate. Other embodiments are described.

Dependencies are inferred from the claim text.