Strain relaxation and multidentate anchoring in n-type perovskite transistors and logic circuits

This is the author accepted manuscriptData availability: Source data are provided with this paper. Additional data related to this work are available from the corresponding authors upon request.Code availability statement: All codes (software) used in the calculation and visualization are publicly available and the condition of their usage in the publication is an appropriate citation.The engineering of tin halide perovskites has led to the development of p-type transistors with field-effect mobilities of over 70 cm2 V-1 s-1 . However, due to their background hole doping, these perovskites are not suitable for n-type transistors. Ambipolar lead halide perovskites are potential candidates, but their defective nature limits electron mobilities to around 3-4 cm2 V-1 s-1, which makes the development all-perovskite logical circuits challenging. Here, we report formamidinium lead iodide perovskite n-type transistors with field-effect mobilities of up to 33 cm2 V-1s-1 measured in continuous bias mode. This is achieved through strain relaxation of the perovskite lattice using a methyl ammonium chloride additive, followed by suppression of undercoordinated lead through tetramethyl ammonium fluoride multidentate anchoring. Our approach stabilizes the alpha phase, balances strain, and improves surface morphology, crystallinity, and orientation. It also enables low-defect perovskite–dielectric interfaces. We use 46 the transistors to fabricate unipolar inverters and eleven-stage ring oscillator

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

This is the author accepted manuscript.Data availability: The data that support the findings of this study are available from the corresponding authors upon reasonable request.Code availability statement: All codes (software) used in the calculation and visualization are publicly available and the condition of their usage in publication is an appropriate citation.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.Korea Research Foundatio