Self‐Rectifying Enhanced Bipolar Resistive Switching Mechanism in Cu₂ZnSiS₄ Thin Films: The Impact of Porous Grain Boundaries

Resistive switching (RS) behavior in kesterite‐based materials has garnered significant attention for its potential in nonvolatile memory applications. This work investigates the RS properties of Cu 2 ZnSnS 4 (CZTS) and Cu 2 ZnSiS 4 (CZSiS) thin films for potential applications in resistive memory devices. By substituting Sn with Si in CZTS, CZSiS is developed which is a material composed of Earth‐abundant and nontoxic elements, and its RS performance with CZTS is compared. Both materials are fabricated as metal–semiconductor junctions, with CZSiS demonstrating superior switching characteristics, including a high switching ratio (≈1725) and stable endurance up to 150 cycles. Impedance spectroscopy and cyclic I–V analysis reveal that the enhanced RS behavior of CZSiS is attributed to the efficient formation of conducting filaments in the intergrain regions. The findings suggest that CZSiS is a promising candidate for low‐cost, high‐performance resistive memory applications.