Regulating Photocurrent Polarity Reversal Point in α-Ga<sub>2</sub>O<sub>3</sub> Nanorod Arrays for Combinational Logic Circuit Applications
Hangjie Xu, Lipeng Deng, Yuexing Cheng, Chao Wu, Kai Chen, Daoyou Guo
Abstract
To enhance computing power, a broader understanding of semiconductors is imperative. Conventional semiconductor technology has reached its limits, necessitating the exploration and development of optoelectronic approaches. Among these, the photoelectrochemical (PEC) detector has emerged as a fresh photodetection paradigm. This study rigorously investigates the indispensability of advancing PEC semiconductor logic devices. By judiciously modifying the α-Ga 2 O 3 sponge’s porous nanorod arrays (NRAs), photocurrent attributes are tailored via the dropwise addition of titanium carbide aqueous solution, conferring inherent self-powering characteristics to the device. Concurrently, leveraging two-dimensional titanium carbide as a modifier for gallium oxide empowers control over the polarity reversal point of the photocurrent in the photoelectrochemical photocurrent switching (PEPS) effect. This enhancement amplifies the exploitation of the PEPS effect in semiconductor devices, attributed to Ti 3 C 2 T x ’s dual response, both internal and external, under 254 nm deep ultraviolet illumination, thus intensifying carrier generation. Consequently, the interplay of charge transfer between Ti 3 C 2 T x and α-Ga 2 O 3 expedites electron injection into the semiconductor, ultimately elevating α-Ga 2 O 3 ’s surface Fermi level. Moreover, diverse degrees of Ti 3 C 2 T x modification afford distinct reactive sites and channels within α-Ga 2 O 3, thereby elevating the reaction probabilities. Subsequent utilization of the PEPS effect yields PEC logic gates XOR and AND gates. Building upon this, a consolidated architecture integrates the combinational logic circuit elements─half adder and four-input XOR gate─streamlining the circuit’s complexity and enhancing its utility in verification, computation, error detection, encoding, and decoding. Consequently, Ti 3 C 2 T x /α-Ga 2 O 3 NRAs present a promising photoanode prospect. Notably, this marks the pioneering construction of logic components, such as a half adder and a four-input XOR gate, within a gallium oxide PEC device.