Unraveling the Heterointegration of 3D Semiconductors on Graphene by Anchor Point Nucleation

Abstract

The heterointegration of graphene with semiconductor materials and the development of graphene‐based hybrid functional devices are heavily bound to the control of surface energy. Although remote epitaxy offers one of the most appealing techniques for implementing 3D/2D heterostructures, it is only suitable for polar materials and is hugely dependent on the graphene interface quality. Here, the growth of defect‐free single‐crystalline germanium (Ge) layers on a graphene‐coated Ge substrate is demonstrated by introducing a new approach named anchor point nucleation (APN). This powerful approach based on graphene surface engineering enables the growth of semiconductors on any type of substrate covered by graphene. Through plasma treatment, defects such as dangling bonds and nanoholes, which act as preferential nucleation sites, are introduced in the graphene layer. These experimental data unravel the nature of those defects, their role in nucleation, and the mechanisms governing this technique. Additionally, high‐resolution transmission microscopy combined with geometrical phase analysis established that the as‐grown layers are perfectly single‐crystalline, stress‐free, and oriented by the substrate underneath the engineered graphene layer. These findings provide new insights into graphene engineering by plasma and open up a universal pathway for the heterointegration of high‐quality 3D semiconductors on graphene for disruptive hybrid devices.

Sustainable Production of Ultrathin Ge Freestanding Membranes

“…2D-assisted epitaxy, in theory, could eventually offer infinite reuse of the substrate. However, it is still in relatively early research stages, especially in case of group IV materials such as Ge, which were demonstrated for the first time in late 2022 [39], using a new approach on local nucleation and lateral overgrowth on the 2D interface [40,59]. Moreover, other challenges such as large surface growth and the transfer of high-quality interfaces need to be resolved for its viable application [60].…”

“…The main domains and applications of Ge FSM are illustrated in Figure 1. Various techniques have been demonstrated for Ge FSM fabrication, including substrate thinning [34], epitaxial liftoff [35,36], Smart cut technology [37], mechanical spalling [38], 2Dassisted epitaxy [39,40], and Germanium-on-Nothing [41,42]. Among them, the porosification lift-off technique has recently received significant attention and development thanks to its potentially high-throughput and cost-effective process [20,25].…”