DLTS Study on Deep Levels Formed in Plasma Hydrogenated and Subsequently Annealed Silicon
P-n junctions are created in p-type Czochralski silicon after a low temperature (270°C) hydrogen plasma exposure. This is attributed to the formation of hydrogen-related shallow donors. A deep level (E1) with an activation energy of about EC-0.12 eV is observed by DLTS measurement and assigned to a metastable state of the hydrogen-related shallow donors. At an annealing temperature of 340°C, the E1 centres disappear and oxygen thermal donors appear. The concentrations of the oxygen thermal donors are found typically to be 2-3 decades lower than that required for over-compensating the initial p-type doping and for contributing the excess free carriers.
B. Pichaud, A. Claverie, D. Alquier, H. Richter and M. Kittler
Y. L. Huang et al., "DLTS Study on Deep Levels Formed in Plasma Hydrogenated and Subsequently Annealed Silicon", Solid State Phenomena, Vols. 108-109, pp. 547-552, 2005