The p-type characteristic of solution-processed metal halide perovskite transistors means that they could be used in combination with their n-type counterparts, such as indium–gallium–zinc-oxide transistors, to create complementary metal–oxide–semiconductor-like circuits. However, the performance and stability of perovskite-based transistors do not yet match their n-type counterparts, which limit their broader application. Here we report high-performance p-channel perovskite thin-film transistors based on inorganic caesium tin triiodide semiconducting layers that have moderate hole concentrations and high Hall mobilities. The perovskite channels are formed by engineering the film composition and crystallization process using a tin-fluoride-modified caesium-iodide-rich precursor with lead substitution. The optimized transistors exhibit field-effect hole mobilities of over 50 cm2 V−1 s−1 and on/off current ratios exceeding 108, as well as high operational stability and reproducibility.

Despite the impressive development of metal halide perovskites in diverse optoelectronics, progress on high-performance transistors employing state-of-the-art perovskite channels has been limited due to ion migration and large organic spacer isolation. Herein, we report high-performance hysteresis-free p-channel perovskite thin-film transistors (TFTs) based on methylammonium tin iodide (MASnI3) and rationalise the effects of halide (I/Br/Cl) anion engineering on film quality improvement and tin/iodine vacancy suppression, realising high hole mobilities of 20 cm2 V−1 s−1, current on/off ratios exceeding 107, and threshold voltages of 0 V along with high operational stabilities and reproducibilities. We reveal ion migration has a negligible contribution to the hysteresis of Sn-based perovskite TFTs; instead, minority carrier trapping is the primary cause. Finally, we integrate the perovskite TFTs with commercialised n-channel indium gallium zinc oxide TFTs on a single chip to construct high-gain complementary inverters, facilitating the development of halide perovskite semiconductors for printable electronics and circuits.

Semiconducting ink based on 2D single‐crystal flakes with dangling‐bond‐free surfaces enables the implementation of high‐performance devices on form‐free substrates by cost‐effective and scalable printing processes. However, the lack of solution‐processed p‐type 2D semiconducting inks with high mobility is an obstacle to the development of complementary integrated circuits. Here, a versatile strategy of doping with Br2 is reported to enhance the hole mobility by orders of magnitude for p‐type transistors with 2D layered materials. Br2‐doped WSe2 transistors show a field‐effect hole mobility of more than 27 cm2 V−1 s−1, and a high on/off current ratio of ≈107, and exhibits excellent operational stability during the on‐off switching, cycling, and bias stressing testing. Moreover, complementary inverters composed of patterned p‐type WSe2 and n‐type MoS2 layered films are demonstrated with an ultra‐high gain of 1280 under a driving voltage (VDD) of 7 V. This work unveils the high potential of solution‐processed 2D semiconductors with low‐temperature processability for flexible devices and monolithic circuitry.

The application of organic–inorganic perovskites has recently attracted increasing interest due to their excellent optoelectronic properties. As an emerging semiconductor, the doping capability and efficiency of these materials require further clarification but have rarely been studied previously. In this study, diverse monovalent cations, Cu+, Na+, and Ag+, are incorporated into phenethylammonium tin iodide ((PEA)2SnI4) perovskite, and the resultant lattice structural variation, film properties, and thin-film transistor performance are systematically investigated by combining theoretical and experimental methods. Owing to their unique composition and octahedral unit, perovskite semiconductors possess strong ‘substitution doping tolerance’ with the aliovalent cation dopants. Theoretical studies claim that the hypothetical monovalent cation substitution on the Sn2+ B-site creates undesired vacancies and destabilizes the perovskite lattice structure. The experimental results show that the incorporated foreign aliovalent cations are not doped inside the perovskite lattice but segregated along the grain boundaries. Benefiting from the excellent hole transport property and passivation effect of copper iodide (CuI), the CuI–(PEA)2SnI4 heterostructure composite channel layers exhibit much improved film properties and device performance, including doubled field effect mobility, compared with the pristine ones.

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