Scalable Device Array for Statistical Characterization of BTI-Related Parameters

A device array circuit, scalable in terms of the number of transistors used, is proposed. The proposed array facilitates accurate and simultaneous bias voltage application to a large number of devices, making it suitable for the measurement-based statistical characterization of device degradation, known as bias temperature instability. Using the proposed array, the degradation measurement of thousands of transistors is made possible in a practical amount of time. The experimental results show that the defect-centric model can approximate the statistical variation in magnitudes of threshold voltage shifts (ΔV_TH) and that the variance of ΔV_TH bears an inverse relationship to the channel areas of transistors. The degradation variability under ac stress conditions is also presented for the first time.