SUPPRESSION OF TITANIUM DISILICIDE FORMATION ON HEAVILY ARSENIC-DOPEDSILICON SUBSTRATE

Titanium disilicide formation on heavily arsenic-doped silicon substra te was investigated. The suppression of disilicide formation was due t o the existence of an incubation time, but not to the reduction of the disilicide formation rate. The incubation time for disilicide formati on was induced when the amount of arsenic was above a critical concent ration (5 x 10(20) atoms/cm(3)) at the silicon surface. Arsenic concen tration higher than the critical value induced the retardation of tran sformation from the titanium-rich silicides to the disilicide. When th e arsenic concentration was lower than the critical value, the disilic ide formation occurred without an incubation time.