Ultrashallow diffused n+p junction using antimony for device applications

Abstract

Experimental characteristics of ultrashallow n+p junctions manufactured by vacuum evaporation of antimony (Sb) and silicon (Si), followed by heat treatments to recrystallize the amorphous silicon, are presented. It is found that the n+p junction is located less than 300 Å inside the crystalline silicon and that all Sb is redistributed within the regrown film. Comparisons with Schottky (Sb-Si) diodes show that with a heat treatment at 900 °C, the diodes convert fully from Schottky type to n+p type. Furthermore, normally off-type junction field-effect transistors have been fabricated using these n+p junctions as gate junctions, and the characteristics are presented together with data concerning threshold voltage variations. Also, the subthreshold characteristics of these junction field-effect transistors are presented. The behavior in the subthreshold region is found to be excellent.

Activation of Sb in Ultra-Shallow Poly-Silicon Emitters Using Rapid Thermal Processing.

“…Earlier, these junctions have successfully been used as a gate material in p-type JFETs, with a gate junction depth below 300 A from the monocrystalline silicon surface [1].…”

Cathodic arc ion implantation for semiconductor devices

“…Recently, together with the research on ultrashallow junctions, antimony has attracted much attention as a candidate for doping ultrashallow junctions [11][12][13][14] in very large scale integrate ͑VLSI͒ technology because of the following unique features of antimony: 13 ͑1͒ The diffusion coefficient of antimony is small and its concentration enhancement is also less pronounced; 15 ͑2͒ for a given mean ion implant depth antimony has less straggle; and ͑3͒ the lateral straggle at the mask edges is even more significantly diminished. Recently, together with the research on ultrashallow junctions, antimony has attracted much attention as a candidate for doping ultrashallow junctions [11][12][13][14] in very large scale integrate ͑VLSI͒ technology because of the following unique features of antimony: 13 ͑1͒ The diffusion coefficient of antimony is small and its concentration enhancement is also less pronounced; 15 ͑2͒ for a given mean ion implant depth antimony has less straggle; and ͑3͒ the lateral straggle at the mask edges is even more significantly diminished.…”