Self-crystallization and reduced contact resistivity by hot phosphorus ion implant in germanium-tin alloy

Abstract

We investigated the effect of phosphorus ion (P+) implant temperature on the material properties of epitaxial GeSn alloy and the electrical characteristics of GeSn n+/p diodes. Hot P+ implant maintains the single crystallinity of GeSn during implant. In addition, samples implanted at elevated temperature followed by a subsequent RTA at 450 °C for 3 minutes achieve a lower contact resistivity compared with those implanted at room temperature, indicating a higher P dopant activation.