Thermal Annealing of High Dose P Implantation in 4H-SiC

TL;DR

This study investigates the effectiveness of double step annealing in reducing defects and activating phosphorus doping in high-dose implanted 4H-SiC, finding limited success in restoring crystallinity and dopant activation.

Contribution

It evaluates a specific double step annealing process for high-dose P implantation in 4H-SiC using multiple characterization techniques.

Findings

Neither annealing at 1650-1750°C nor at 1500°C achieved satisfactory crystallinity.

Dopant activation remained below 1% after annealing.

Defect density was not sufficiently reduced by the tested annealing protocols.

Abstract

In this work, we have studied the crystal defectiveness and doping activation subsequent to ion implantation and post-annealing by using various techniques including photoluminescence (PL), Raman spectroscopy and transmission electron microscopy (TEM). The aim of this work was to test the effectiveness of double step annealing to reduce the density of point defects generated during the annealing of a P implanted 4H-SiC epitaxial layer. The outcome of this work evidences that neither the first, 1 hour isochronal annealing at 1650 - 1700 - 1750 {\deg}C, nor the second one, at 1500 {\deg}C for times between 4 hour and 14 hour, were able to recover a satisfactory crystallinity of the sample and achieve dopant activations exceeding 1%.