A method for fabricating a semiconductor device using a high-temperature ion implantation process includes providing a substrate including a plurality of fins. In some examples, a mask material is deposited and patterned to expose a group of fins of the plurality of fins and a test structure. By way of example, a first ion implantation may be performed, at a first temperature, through the group of fins and the test structure. Additionally, a second ion implantation may be performed, at a second temperature greater than the first temperature, through the group of fins and the test structure. In various examples, an interstitial cluster is formed within the group of fins and within the test structure. In some embodiments, an anneal process is performed, where the anneal process serves to remove the interstitial cluster from the group of fins and form at least one dislocation loop within the test structure.