Charge distribution at metal-multilayered semiconductor interfaces

TL;DR

This study uses first-principles calculations to analyze charge distribution mechanisms at metal-multilayered MoS2 interfaces, revealing how dimensionality and work function influence electronic interactions and charge transfer effects.

Contribution

It provides a systematic investigation of charge distribution and interaction mechanisms at metal-MoS2 interfaces, highlighting the role of dimensionality and work function in these systems.

Findings

Charge distribution depends on metal substrate dimensionality and work function.

Push back effect and metal induced gap states dominate at 3D metal-MoS2 interfaces.

Charge transfer and covalent-like features are observed at specific interfaces.

Abstract

Thicknesses-dependent performances of metal-multilayered semiconductor junctions have attracted increasing attention, but till present, the mechanism of interaction and the resulting charge distribution at interfaces which control the Schottky barrier and band offset between the semiconductor layers have not been systematically studied. Based on first-principles calculations, the nature and strength of the non-bonding interactions at Metal-MoS2 (M-S) and MoS2-MoS2 (S-S) interfaces in meta-multilayered MoS2 are investigated. We show that the charge distribution at M-S interfaces depends sensitively on the dimensionality and work function of metal substrates: 1) push back effect and metal induced gap states play a main role at 3D metal-MoS2 interfaces; 2) charge transfer occurs in Mo2C(OH)2 (or Mo2CO2)-MoS2 interfaces which means electron distribution is determined by the band alignment of metal and MoS2; 3) covalent-like feature appears at Mo2CF2-MoS2 interface. The S-S interface inherit the charge redistribution at M-S interface for 2D metal-2L MoS2 junction, and have a depinning effect for M-S interface in 3D metal-2L MoS2 junction. We are trying to start drawing general conclusions and developing new concepts to understand metal-multilayered semiconductor interfaces in the strong interaction limit, where charge-transfer effects must be taken into consideration in this paper.