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In this thesis, the impact of applying BF2+ implanted
cobalt polycide formed by the different process conditions as
gate electrode was firstly studied. From the results of varying
Co thickness, it was observed that breakdown field and charge to
breakdown decrease (Qbd) still occur even though no degradation
of silicide for Co-30nm sample annealed at 900C. We ruled out
the possibility that the degradation is due to metal
contamination. In the experimental of varying doseof BF2+
implant, it was observed that the lower dose BF2+ implanted
with, the better Qbd the gate oxide had irrespective of the
annealing temperature. It was attributed to the boron
penetration effect. In another topic, a process with NF3
treatment is proposed to improve the thermal stability of the
cobalt polycide p+-gate and the integrity of gate oxide. It has
been demonstrated in several researches that flourine or
nitrogen implantation can improve the thermal stability of the
polycide gate contact by increasing the interface energy and
dielectric strength. As proposed in this thesis, NF3 passivation
is used by the conventional Low Pressure(LP) thermal treatments.
In this experiment, the value and yield of charge to breakdown
(Qbd) has been dramatically improved by NF3 passivation
irrespective of the annealing temperature. Ascompare to the
technique of ion implantation, this method also provides alow
cost and high throughput for mass production.
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