Very low effective Schottky barrier height for erbium disilicide contacts on n-Si through arsenic segregation

TL;DR

This study demonstrates that ErSi2-x contacts on n-Si can achieve extremely low Schottky barrier heights below 0.12 eV through arsenic segregation, enabling low-temperature fabrication of efficient contacts.

Contribution

It reveals that arsenic segregation during ErSi2-x formation leads to very low effective Schottky barriers on n-Si, independent of dopant redistribution.

Findings

Effective SBH below 0.12 eV achieved at moderate annealing temperatures.

Enhanced arsenic dose reduces the annealing temperature needed for low SBH.

Low thermal budget process for ErSi2-x/n-Si contacts.

Abstract

The segregation of As+ ions implanted into thin Er films deposited on n-Si substrates is studied after ErSi2-x formation. The same lowering of the effective Schottky barrier height (SBH) below 0.12 eV is obtained at moderate annealing temperatures, regardless of the redistribution of As dopants at the ErSi2-x/Si interface. On the other hand, if the implanted dose is slightly enhanced, the annealing temperature required to reach sub-0.12-eV effective SBH can be further reduced. This process enables the formation of very low effective SBH ErSi2-x/n-Si contacts with a low thermal budget.