Surface activation of Si-based Schottky diodes by bacterial biosynthesized AgInSe2 trimetallic alloy nanoparticles with evidenced negative capacitance and enhanced electro-dielectric performance

Semiconductor surface activation aims to modify the surface characteristics of a semiconductor material, such as its work function, surface energy, and chemical composition to improve its electrical properties and enable efficient charge transport across the device. Here, AgInSe 2 complex trimetallic alloy was utilized as an interfacial layer in Si-based Schottky diodes and served as a semiconductor surface activator. The alloy nanoparticles were produced by green bacterial biosynthesis for the first time in the literature. XRD and micro-Raman manifested a nanostructured polycrystalline nature of the alloy with rhombohedral AgInSe 2 and cubic Ag crystal phases. From the electrical measurements, the diode with AgInSe 2 interfacial layer showed superior electrical and dielectric characteristics compared to the pure diode at room temperature. The introduction of interlayer resulted in a smaller ideality factor, larger barrier height, higher rectification ratio, lower leakage current, and better dielectric properties compared to the pure diode. The diode also recorded a negative permittivity, up to a certain frequency, that could enhance its performance when integrated into electronic circuits. The evidenced negative capacitance and its possible benefits in Schottky diodes are elaborated. The electro-dielectric enhancement was attributed to AgInSe 2 -induced semiconductor surface activation through the stimulation of the unpaired reactive silicon atoms at the semiconductor surface.