Jaydip Guha

Two‐Dimensional Cross‐Sectional Doping Profile Study of Low Energy High Dose Ion Implantations Using High Vacuum Scanning Spreading Resistance Microscopy (HV‐SSRM) and Electron Holography

High vacuum scanning spreading resistance microscopy (HV‐SSRM) and electron holography (EH) methods are used to study two‐dimensional (2D) cross‐sectional doping profiles of low energy high dose ion implantations including conventional beam‐line 75As implant and AsH3 plasma doping (PLAD). Both methods show quantitative definition of junction depths xj in vertical and lateral directions, and have been demonstrated to be powerful techniques for 2D doping profiling study. It has been found that AsH3 PLAD with −10 kV voltage and 1×1016/cm2 dose shows slightly deeper junction depth xj, both of vertical xj(V) and lateral xj(L) and with slightly larger xj(L)/xj(V) ratio than beam‐line 75As implant with 10 keV energy and 8×1015/cm2 dose. Good correlations among 2D HV‐SSRM doping profiles, 2D EH doping profiles, 2D doping profile simulation, and 1D SIMS/ARXPS As profiles have been demonstrated. Very good correlation between 2D doping profiles and device parameters has been demonstrated.

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 B<inf>2</inf>H<inf>6</inf> plasma doping (PLAD). It has been found that B<inf>2</inf>H<inf>6</inf> PLAD with −6kV voltage and 2×10¹⁶/cm² dose shows slightly deeper junction depth x<inf>j</inf>, both of the vertical x<inf>j</inf>(V), and lateral x<inf>j</inf>(L) and with slightly larger x<inf>j</inf>(L)/x<inf>j</inf>(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<inf>j</inf>, but with a similar x<inf>j</inf>(L)/x<inf>j</inf>(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.