Unipolar Differential Logic for Large-Scale Integration of Flexible a-IGZO Circuits

A new unipolar differential logic (UDL) for the large-scale integration of amorphous In-Ga-Zn-O (aIGZO) digi- tal circuits is proposed. Only single-threshold, single-gate, aIGZO thin-film transistors are required. The proposed UDL logic gates are very insensitive to the transistor parameters variations (i.e. threshold voltage, mobility, off-current, subthreshold slope) that are inherently due to the large-area low-temperature fabrication processes and to the operating conditions. To assess the UDL effectiveness, a wide range of parameters variations is considered: thanks to the proposed architecture up to 1.5 × 10^7 UDL gates can be integrated with a yield greater than 90%.