Anomalous activation of shallow B+ implants in Ge

作者：Yates B R^*; Darby B L; Rudawski N G; Jones K S; Petersen D H; Hansen O; Lin R; Nielsen P F; Kontos A

来源：Materials Letters, 2011, 65(23-24): 3540-3543.

DOI：10.1016/j.matlet.2011.07.093

• Ge
• B
• Dopant activation
• Micro four point probe
• TEM

The electrical activation of B+ implantation at 2 keV to doses of 5.0 x 10(13)-5.0 x 10(15) cm(-2) in crystalline and pre-amorphized Ge following annealing at 400 degrees C for 1.0 h was studied using micro Hall effect measurements. Preamorphization improved activation for all samples with the samples implanted to a dose of 5.0 x 10(15) cm(-2) displaying an estimated maximum active B concentration of 4.0 x 10(20) cm(-3) as compared to 2.0 x 10(20) cm(-3) for the crystalline sample. However, incomplete activation was observed for all samples across the investigated dose range. For the sample implanted to a dose of 5.0 x 10(13) cm(-2), activation values were 7% and 30%, for c-Ge and PA-Ge, respectively. The results suggest the presence of an anomalous clustering phenomenon of shallow B+ implants in Ge.

• 出版日期2011-12