Quantifying the Effect of Guard Rings and Guard Drains in Mitigating Charge Collection and Charge Spread

Abstract

3D-TCAD simulations in a 130-nm process are used to show the effect of guard rings and guard drains in mitigating charge collection and charge sharing between nodes. Experimental results quantifying the reduction in SET pulse width and the error cross section were obtained with the use of SET pulse width and SET error rate measurement test circuits fabricated in 130-nm and 180-nm processes. Results indicate that guard drains results in 30% lower error cross section compared to guard ring circuits.