An experimental analysis of localized lifetime and resistivity control by Helium

In this work we present an experimental study on the effects of helium implantation in silicon. Doses in the range 1 times 10
¹⁰
- 5 times 10
¹¹
atoms/cm
²
have been analysed. Results show that, increasing the dose, a saturation effect on the minimum lifetime that can be achieved occurs, while a marked effect on the resistivity of the material appears. The temperature dependence of the resistivity show that changes are due to a trap effect related to an energy level in the bandgap placed at Ec-0.23 eV that is the same of the dominant recombination center induced by helium implantation