Ordered oxygen vacancies modulate hole transport and enhance the photoresponse in p-type SnO thin films

Two-dimensional p-type oxide semiconductors have garnered significant interest due to their advantageous properties and practical applicability. Among them, tin monoxide (SnO) emerges as a standout candidate, due to the intrinsic p-type conductivity and the structure tunability. Here, we mechanically exfoliated SnO into few-layer flakes and discovered the formation of ordered oxygen vacancies within the films. These vacancies efficiently modulate the local electronic structure, significantly boosting the electrical properties of SnO. The SnO films exhibited a hole mobility of 7.3 cm2/V·s and an on/off ratio above 105 at room temperature, exceeding the values reported for other intrinsic p-type oxides. Moreover, SnO demonstrated strong photodetection across a broad spectral range, with an exceptional ultraviolet responsivity of 1.1 × 104 A/W. The devices also demonstrate memory and perception capabilities, highlighting their potential for neuromorphic applications. Together, these findings lay a solid foundation for the advancement of complementary circuit technologies and their integration into intelligent electronic devices.