Morphology of the silicon implanted interface of a polysilicon/single crystal silicon structure

Abstract Employing high resolution TEM, it was shown that the morphological change of polysilicon/single crystal silicon (poly-Si/Si) interface induced by silicon implantation and subsequent annealing at 900° C for 30 min greatly depended on implantation dose. After annealing, the interfacial native oxide layer implanted with 3 × 10 15 cm −2 Si was broken up into a discontinuous layer, which still remained at the interface. For the interface implanted with 1 × 10 16 cm −2 Si, however, “oxide balls” of 10–20 A diameter were formed and the distribution of the oxide balls was broadened (about 100 A width). SIMS analysis revealed that for an interface implanted with 1 × 10 16 cm −2 Si, the distribution of oxygen atoms near the interface broadened by the implantation and that it slightly narrowed after annealing. These morphological changes influenced the contact resistance of poly-Si/Si interface, especially in a sub-half-μm region.