Wafer-scale growth of ultrathin amorphous tellurium oxide via pulsed laser deposition for p-channel transistors

Oxide semiconductors are promising building blocks for complementary transparent electronics, and however p-type oxide semiconductors suffer from limited material choice and low carrier mobility as compared to their n-type counterparts. Herein, we demonstrate the wafer-scale growth of amorphous tellurium oxide (TeO_x) thin films with p-type transport characteristics, through a pulsed laser deposition (PLD) method coupled with a low-temperature post-annealing treatment. Ultrathin TeO_x with the thickness down to several nanometers is prepared by oxidizing the Te thin films precisely deposited and controlled by PLD technique, where their stoichiometric ratio can be modulated by the annealing time. Moreover, the optical bandgap of TeO_x is found to be varied from 0.59 eV to 0.98 eV during the oxidation process. As a result, the TeO_x-based field-effect transistors exhibit a competitive hole transport behavior as compared to reported amorphous TeO_x, along with the current on/off ratio exceeding 2 × 10³ (1.3 × 10⁷) and hole mobility of 47.6 ± 2 cm²·V^-1·s^-1 (41.8 ± 0.5 cm²·V^-1·s^-1) at 300 K (80 K). Our findings promise a facile and controllable approach to synthesize wafer-scale and ultrathin p-type oxides for future complementary electronics.