Two Transistors Voltage-Measurement-Based Test Structure for Fast MOSFET Device Mismatch Characterization

This work presents a test structure targeted to measure MOSFET mismatches with a fast method. It relies on two single-spot voltage measurements in order to extract ΔV
_TH
and Δβ/β separately. The new methodology gives a theoretical increase in the measurement speed of 30× (23.17× in practice). The coefficient of determination (R
²
) of the linear regression analysis is used to compare standalone transistor measurements against the new proposed methodology. The correlation in the data demonstrates values not less than 0.94 (R
²
≥ 0.94). The test structure can reproduce parameter correlations, and it is capable of extracting MOSFET mismatch design parameters, such as Pelgrom's A
_V(TH)
, with an error of 2% and A
_β
, with a negligible error. The experimental data presented herein are taken from measurements in prototypes fabricated in a 65nm CMOS bulk process. The whole circuit is composed of 16 2D addressable DUT device matrices, each having 256 same-size closely-placed MOSFET devices, totaling 4,096 MOS devices used in single-type (NMOS) transistor array.