Comparison of indium metrology using LEXES and SIMS [semiconductor doping]

There has been increasing interest in using Indium (In⁺) as the channel and substrate dopant in place of the lighter boron atom. Indium is a heavier atom and hence yields a more controllable and steeper dopant profile, which is extremely important to reduce short channel effects (SCE) in modem MOSFETs. Studies have been done on using In as the channel dopant and devices with improved SCE have been reported. In+ has also been studied as a halo implant species to enhance the short channel performance of devices. However, indium shows enhanced diffusivity in the presence of some source of interstitials. To this effect, work has been done to study the diffusion of In in silicon under neutral and oxidizing ambients. In this paper, we study and present experimental results on the indium diffusion behavior and dose loss as a function of different damage structures and anneal conditions, utilizing low energy electron induced X-ray emission spectrometry (LEXES) and secondary ion mass spectrometry (SIMS) analysis techniques.