Diffusion and Dopant Activation in Germanium: Insights from Recent Experimental and Theoretical Results

E N Sgourou,N Kuganathan,A Chroneos,Y Panayiotatos,R V Vovk

doi:10.3390/app9122454

Abstract

Germanium is an important mainstream material for many nanoelectronic and sensor applications. The understanding of diffusion at an atomic level is important for fundamental and technological reasons. In the present review, we focus on the description of recent studies concerning n-type dopants, isovalent atoms, p-type dopants, and metallic and oxygen diffusion in germanium. Defect engineering strategies considered by the community over the past decade are discussed in view of their potential application to other systems.

Highlights

For over a decade, Ge has been actively considered for many nanoelectronic and sensor applications, as it has a number of material property advantages over Si or alternative materials such as silicon–germanium (Si1–x Gex ) alloys
Apart from C, which is mainly introduced during the processing ( at smaller concentration constrain A-centers and reduce the diffusivities of n-type dopants as compared to Si lattices) [1], isovalent atoms are considered in Ge as co-dopants that will be useful
Sn theinconcentration ofmore the VO. This is analogous to the defectwill engineering strategies the lattice most vacancies be trapped by the Snemployed atoms using isovalent dopants to minimize thepairs

Summary

Introduction

Ge has been actively considered for many nanoelectronic and sensor applications, as it has a number of material property advantages over Si or alternative materials such as silicon–germanium (Si1–x Gex ) alloys. The methodological advances in the past years and their wide spread (for example, density functional theory (DFT) and time of flight secondary ion mass spectrometry (ToF-SIMS)) have enabled the better understanding of materials at an atomistic level [66,67,68,69,70,71,72,73,74,75,76,77,78,79,80] These methods can resolve the energetics of atomic diffusion, provide evidence of the diffusion mechanism, the formation of clusters, and other electronic and mechanical properties. The latter is mainly concerned with recent results on Pd diffusion, which recently calculated a very low migration energy barrier of Pd interstitial (Pdi ) diffusion

Self-Diffusion

Tetravalent

Diffusion thePV

Metalenergy

Oxygen Diffusion

Summary