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Palladium (Pd) electrodes have enabled superior performance in Te‐based devices. Theory predicts strong Fermi level (EF) pinning near the Te valence band, which likely explains the predominant p‐type conduction in Te transistors. The effects of the native TeOx on the contact polarity has not been explored. In this work, X‐ray and ultraviolet photoelectron spectra (XPS and UPS, respectively) reveal the native surface oxide de‐pins the EF between Pd and trigonal Te (t‐Te) and can reduce contact resistance of hole and electron contacts to Te for back end of line‐compatible complementary logic circuits. Atomic hydrogen reduces the native t‐Te oxide below the XPS detection limit, after which, the EF resides near the t‐Te conduction band edge. Therefore, an n‐type band alignment is formed between Pd and t‐Te via an atomic hydrogen treatment. Furthermore, UPS shows the EF is pinned near the t‐Te conduction band edge. XPS indicates the formation of a PdTex intermetallic at the Pdt‐Te interface also affects the electrostatics of the interface. The concentration of PdTex is 40% higher when TeOx is removed from the t‐Te surface before Pd metallization, likely the root cause of the low (pinned) work function when the native oxide is absent. [ABSTRACT FROM AUTHOR]

Atomically thin tungsten diselenide (WSe2) is a promising 2D semiconductor for nanoelectronics and optoelectronics. Using UV ozone and low‐power O2 plasma treatments, it is demonstrated that the formation of WSe2(1−x)O2x (WSeyOx) leads to hysteretic behavior in vertical transport measurements and also enables to an improvement in the p‐type transfer characteristics in lateral transport measurements. The amount of oxidation correlates well with the resistive switch behavior in oxidized WSe2/graphene, and WSeyOx formation under the electrical contact of the horizontal devices leads to increased p‐branch on/off by 100×. In addition to its effect for residue removal, oxidation on field effect transistor channel also helps mitigate n‐type dominated transfer characteristics of WSe2 commonly seen on sapphire. It is demonstrated that light oxidation of WSe2 is a multifunctional post‐growth treatment that enables vertical resistive switch junctions, contact improvement, and continuous tuning of transistor transport properties. [ABSTRACT FROM AUTHOR]