Chemical Patterning of High-Mobility Semiconducting 2D Bi2 O2 Se Crystals for Integrated Optoelectronic Devices.

Patterning of high-mobility 2D semiconducting materials with unique layered structures and superb electronic properties offers great potential for batch fabrication and integration of next-generation electronic and optoelectronic devices. Here, a facile approach is used to achieve accurate patterning of 2D high-mobility semiconducting Bi2 O2 Se crystals using dilute H2 O2 and protonic mixture acid as efficient etchants. The 2D Bi2 O2 Se crystal after chemical etching maintains a high Hall mobility of over 200 cm2 V-1 s-1 at room temperature. Centimeter-scale well-ordered arrays of 2D Bi2 O2 Se with tailorable configurations are readily obtained. Furthermore, integrated photodetectors based on 2D Bi2 O2 Se arrays are fabricated, exhibiting excellent air stability and high photoresponsivity of ≈2000 A W-1 at 532 nm. These results are one step towards the practical application of ultrathin 2D integrated digital and optoelectronic circuits.