A three-step healing approach for high performance n-channel perovskite transistors and logical circuits

Abstract

Progress in all-inorganic tin halide perovskites has recently enabled the fabrication of p-channel transistors with mobilities exceeding 50 cm2 V-1 s-1. However, the performance of the n-channel counterparts is currently limited to 4 cm2 V-1 s-1, undermining efforts to realize all-perovskite logical circuits. Herein, we report n-channel hysteresis-free perovskite transistors with electron mobilities of 25.15 cm2 V−1 s−1 combined with exceptional stability upon continuous bias stress. This is achieved through the application of a rational three-step healing approach, consisting of: (i) the addition of methyl ammonium chloride to stabilize the alpha-phase of formamidinium lead iodide; (ii) dilution with tetrahydrofuran to substantially improve the morphology of the perovskite channel; and (iii) surface treatment with tetramethylammonium hexafluorophosphate to further reduce the concentration of ionic bulk and surface defects. Upon applying a short post-annealing of the surface modifier, an unprecedented mobility of 33 cm2 V−1 s−1 is further attained. These transistors are integrated to fabricate unipolar inverters and eleven-stage ring oscillators, paving the path towards all-perovskite logical circuits.