The measurement of electrical activity and Hall mobility of boron and phosphorus ion-implanted layers in silicon†

This paper describes an investigation into the electrical behaviour of shallow implantations of boron and phosphorus in silicon. The clover-leaf Van der Pauw patterns wore denned by planar masking techniques, and were ion implanted to produce a ‘ tailored ’ impurity profile of approximately uniform concentration with depth. It was found that phosphorus implantations became fully electrically active after annealing at a temperature between 620° c and 750° c, whereas the boron implantations required an anneal in excess of 900° c. A subsidiary activity peak, whose magnitude increased with the ion dose, was observed for the boron implantations after annealing at a temperature around 520° c.