Characteristics of p-Type Conduction in P-Doped MoS(2) by Phosphorous Pentoxide during Chemical Vapor Deposition

We demonstrated p-type conduction in MoS(2) grown with phosphorous pentoxide via chemical vapor deposition (CVD). Monolayer MoS(2) with a triangular shape and 15-µm grains was confirmed by atomic force microscopy. The difference between the Raman signals of the A(1g) and E(1)(2g) modes for both the pristine and P-doped samples was 19.4 cm(−1). In the X-ray photoelectron spectroscopy results, the main core level peaks of P-doped MoS(2) downshifted by about 0.5 eV to a lower binding energy compared to the pristine material. Field-effect transistors (FETs) fabricated with the P-doped monolayer MoS(2) showed p-type conduction with a field-effect mobility of 0.023 cm(2)/V⋅s and an on/off current ratio of 10(3), while FETs with the pristine MoS(2) showed n-type behavior with a field-effect mobility of 29.7 cm(2)/V⋅s and an on/off current ratio of 10(5). The carriers in the FET channel were identified as holes with a concentration of 1.01 × 10(11) cm(−2) in P-doped MoS(2), while the pristine material had an electron concentration of 6.47 × 10(11) cm(−2).