Suppression of Interface-Induced Noise by the Control of Electron-Phonon Interactions

We study the influence of various types of contacting media and contact area on the current-fluctuation level in semiconductors, testing the supposition that the electronic noise is governed, in part, by phonon-leaking dynamics to the environment. Using passivated and gettered silicon PIN diodes as experimental test-beds, the presented data lends credence to the prediction that the phonon-refraction characteristics of the semiconductor-metal interface substantially impacts the current fluctuations in the solid. Specifically, if one implements metallic contacts with lower phonon-reflecting characteristics, such as those composed of silver or palladium, or if one increases the area through which phonons can leak to the surrounding environment, then the leakage current decreases.