Use of Sb with Silicides for n Doping of Si
Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Feb-02
For various applications, e.g., the making of shallow junctions, or the fabrication of low resistance ohmic contact to n silicon, one wants to diffuse a dopant element from a silicide to silicon. The silicide can be prepared by codeposition (sputtering, CVD, coevaporation) or by direct metal-silicon reaction. The doping of the silicide itself may take place by implantation, reactive sputtering or CVD from a gaseous source SbH3, SbF3, SbO5, or simply by direct exposure to the gaseous source itself. A problem which is encountered with such procedures is that the affinity of the metal in the silicide, e.g., Ti in TiSi2 for the doping element, might be so high that the dopant reacts with the silicide rather than diffuse to the silicon.