High active carrier concentration in n-type, thin film Ge using delta-doping

We demonstrate CVD in situ doping of Ge by utilizing phosphorus delta-doping for the creation of a high dopant diffusion source. Multiple monolayer delta doping creates source phosphorous concentrations above 1 × 10cm, and uniform activated dopant concentrations above 4 × 10cm in a 600-800nm thick Ge layer after in-diffusion. By controlling dopant out-diffusion, near-complete incorporation of phosphorus diffusion source is shown. ©2012 Optical Society of America OCIS codes: (310.1860) Deposition and fabrication; (310.3840) Materials and process characterization; (140.3380) Laser materials; (160.3130) Integrated optics materials. References and links 1. L. C. Kimerling, D. Ahn, A. B. Apsel, M. Beals, D. Carothers, Y.-K. Chen, T. Conway, D. M. Gill, M. Grove, C.-Y. Hong, M. Lipson, J. Liu, J. Michel, D. Pan, S. S. Patel, A. T. Pomerene, M. Rasras, D. K. Sparacin, K.-Y. Tu, A. E. White, and C. W. Wong, “Electronic-photonic integrated circuits on the CMOS platform,” Proc. 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