2D Homogeneous Integration for Advanced Electronics

With the trend of scaling down, two-dimensional (2D) materials are the most feasible candidate materials with excellent performance at the nanoscale. Among all the 2D semiconductors, the air-stable Bi₂O₂Se (BOSe) has some prominent advantages that make it particularly favorable in this field. The ultrahigh electron mobility (>20000 cm²/V*s at room temperature) and the native high-k Bi₂O₅Se layer make this material system more promising for exploiting advanced electronics. However, complementary metal-oxide-semiconductor (CMOS) integration is a crucial criterion for applying to practical usages. To achieve this goal, the homogeneous integration of BOSe is presented in this work, showcasing the p-type feature via a suitable doping process. The selection of suitable dopants allows one to create the hole carriers. At the same time, the area-selective doping at low temperatures meets the thermal budget (~600 K) in the front-end-of-line process. In view of these existing advantages, we present an epitaxial 2D homojunction for photoelectronics with an on/off ratio (~10⁵) for ultrahigh photodetectivity (~10¹⁴) and a CMOS-like device with compatible electron/hole mobility based on the doped BOSe/BOSe homojunction. Compared with the heterojunction, the homogeneous integration prevents the lattice mismatch and interfacial defects, leading to a better performance. With these efforts, this material system is expected to be more competitive in the next-generational electronics.