Figure 6.

AFM amplitude image of (a) a-Si and (b) a-Ge single layer after annealing at 350°C for 4 h. H flow rate 1.5 ml/min. In (a) bumps (close bubbles with H still inside) are predominant (only one is broken). In (b) large craters, i.e. exploded bumps with escape of H, are by far predominant. Very tiny bumps are also present.