Microstructural anisotropy at the ion-induced rippled amorphous – crystalline interface of silicon

The mechanism of ion-induced ripple-like structure formation at top-surface
and at buried crystalline surface is being studied extensively by several techniques. Using the technique of grazing incidence x-ray scattering, we have measured the degree of amorphization in the region between buried-crystalline and top-surface ripples in silicon as a function of argon-ion dose. Two broad peaks of the amorphous scattering profiles were probed by varying the penetration depth of x-ray and revealed short-range ordering. Our results show that the strong damage of crystalline structure caused by ion bombardment takes place along particular crystallographic directions and displays ion dose dependent behavior.