Two-dimensional cross-sectional doping profiling of boron-based low energy high dose ion implantations using Electron Holography technique

Electron holography, as a powerful method for two-dimensional (2D) doping profiling, is used to study 2D cross-sectional doping profiles of low energy high dose ion implantations including conventional beam-line ¹¹B implant and B₂H₆ plasma doping (PLAD). It has been found that B₂H₆ PLAD with -6 kV voltage and 2 × 10¹⁶/cm² dose shows slightly deeper junction depth x_j, both of the vertical x_j(V), and lateral x_j(L) and with slightly larger x_j(L)/x_j(V) ratio, than beam-line ¹¹B implant with 2keV energy and 5 × 10¹⁵/cm² dose. RTP process with 995°C/20s condition demonstrates higher thermal budget than 1015°C/spike condition - cause deeper x_j, but with a similar x_j(L)/x_j(V) ratio. Good correlations among 2D Electron Holography dopant profiles, 2D dopant profile simulations, and 1D SIMS/ARXPS B profiles have been demonstrated. Very good correlation between 2D Electron Holography doping profiles and device parameters has been demonstrated.