Majorana Zero Modes (MZMs) are an active area of research into potentially non-Abelian quantum states which some authors suggested could offer a degree of protection for decoherence in specially designed quantum computing architectures. MZMs manifest as zero-energy mid-gap states localized at boundaries and topological defects within one-and two-dimensional topological superconductors. One heavily researched platform for realizing MZMs involves proximity coupling a conventional superconductor, most commonly Al and Nb-based alloys, with a semiconductor nanowire with strong spin-orbit coupling (SOC), such as InAs or InSb. The realization of MZMs typically requires external magnetic field or another form of broken symmetry. Recently, advancements have been made in material selection and experimental techniques in such semiconductor-nanowire/superconductor systems, addressing challenges identified during initial experimental efforts that did not yield a clear evidence of MZMs. Approaches include investigating different combinations of semiconductors such as InAs and InSb and superconductors, such as Pb, Sn, Nb, which aim to improve electron mobility and harness larger superconducting gaps and higher critical magnetic fields. A challenge of the semiconductor/superconductor hybrid nanowire configuration is that excessive coupling between the superconducting metal and semiconductor can lead to the "metallization" of the semiconductor, which could hinder achieving the desired topological phase in experimental setups. Theoretical investigations, utilizing the Poisson-Schrödinger equation to model the semiconducting and superconducting properties of the system, have shown that excessive coupling leads to the renormalization of critical semiconductor properties, such as the Landé g-factor and spin-orbit-coupling (SOC), towards values of the metal. Furthermore, undesired band shifts may be induced. The incorporation of a tunnel barrier could serve to modulate the strength of the superconductor-semiconductor coupling, thereby influencing the induced proximity effect, a critical factor in experimental control. Another benefit of a tunnel barrier is that is may act as a passivation layer on top of the semiconductor nanowire, protecting it from environmental effects. Previously, we have explored this idea by using density functional theory (DFT) to investigate CdTe as a prospective tunnel barrier at the InSb/α-Sn interface. It was found that 16 atomic layers (3.5 nm) of CdTe completely shield the InSb from metal induced gap states (MIGS) from the α-Sn, effectively decoupling the semiconductor from the metal. We therefore concluded that the thickness range most likely to be of interest for experimental exploration is 6-10 atomic layers, where some MIGS are still present, indicating coupling between the metal and semiconductor.