Two-dimensional van der Waals thin film transistors as active matrix for spatially resolved pressure sensing

The development of pressure sensor arrays capable of distinguishing the shape and texture details of objects is of considerable interest in the emerging fields of smart robots, prostheses, human-machine interfaces, and artificial intelligence (AI). Here we report an integrated pressure sensor array, by combining solution-processed two-dimensional (2D) MoS2 van der Waals (vdW) thin film transistor (TFT) active matrix and conductive micropyramidal pressure-sensitive rubber (PSR) electrodes made of polydimethylsiloxane/carbon nanotube composites, to achieve spatially revolved pressure mapping with excellent contrast and low power consumption. We demonstrate a 10 × 10 active matrix by using the 2D MoS2 vdW-TFTs with high on-off ratio > 106, minimal hysteresis, and excellent device-to-device uniformity. The combination of the vdW-TFT active matrix with the highly uniform micropyramidal PSR electrodes creates an integrated pressure sensing array for spatially resolved pressure mapping. This study demonstrates that the solution-processed 2D vdW-TFTs offer a solution for active-matrix control of pressure sensor arrays, and could be extended for other active-matrix arrays of electronic or optoelectronic devices.