Trapped charge characterization and removal on floating-gate transistors

Abstract

Floating-gate transistors that have contacts to the lowest metal to the polysilicon floating-gate were fabricated to determine if the lowest metal flow alone could normalize charge across multiple floating gates. The metal contacts did not normalize charge for different numbers of contacts to polysilicon; however, a decreased variance of trapped charge was found when compared to polysilicon floating-gates that have no contacts to lowestmetal. The charge leakage from the floating-gate was negligible after one year, suggesting that layout may play a critical factor in leakage.