Abstract: Heavy metal gettering in silicon devices has been investigated. The mechanisms of phosphorus diffusion gettering are generally attributed to induced dislocations or phosphide. It is shown in this work that the final annealing at low temperature is able to produce gettering action. The new gettering mechanism with segregation annealing is also discussed here. The segregation coefficients between phosphorus doped silicon and intrinsic silicon Suggest that the segregation bemperature must be as low as possible, but compatible with gold mobility.
The segregation annealing technique can be used to obtain a dark current of less than 10pA/mm² in making photoelectric detectors. The general applicability of the technique is also described.

Key words: photoelectric detector, misfit dislocation, segregation coefficient, segregation annealing, phosphorus diffusion gettering, phosphide