A novel mobility-variation-free extraction technique of capacitance coupling coefficient for stacked flash memory cell

We propose a novel extraction technique of the control gate capacitance coupling coefficient (/spl alpha//sub g/) of a stacked gate flash memory cell. Five novel test patterns, that the CBCM (charge based capacitance measurement) method is applied to, are developed to directly measure all the capacitances connected to the floating gate. Comparison of extracted /spl alpha//sub g/ with the TCAD results proves the validity of this technique. Moreover, we have confirmed that conventional techniques, which use the channel current characteristics, overestimate the /spl alpha//sub g/ variation due to channel mobility variation. Therefore direct /spl alpha//sub g/ extraction using our proposed technique is necessary for precise process monitoring.