The authors have recently presented a novel concept for the development of vacuum field emission (VFE) differential amplifier (diff-amp) based on a matched pair of carbon nanotube (CNT) triodes and reported the preliminary device characteristics. In this study, they report the development of a CNT VFE diff-amp using CNT emitter arrays with smaller gate aperture, obtaining better device performance after postsynthesis rapid thermal annealing treatment. A pair of well-matched 2 mu m circular triode arrays showed a gate turn-on voltage of similar to 40 V and displayed similar triode characteristics in the saturation region. Moreover, the proposed two-step analytical model shows that the common-mode rejection ratio (CMRR) in decibels has a linear relationship with the applied gate voltage for the improved dual-triode diff-amp. In addition, the diff-amp, demonstrates high CMRR (34-58 dB) over a wide operating region. (c) 2007 American Vacuum Society.