Table 1. The values of Ge concentration, x, and layer thickness, d, for super-thin samples evaluated from TEM, high-resolution rocking curve and reflectivity measurements.

d TEM (nm)	x	d (nm)	d XRR (nm)	x XRR
2.0 (5)	0.60 (1)	1.40 (6)	1.99 (1)	0.601 (4)
3.0 (5)	0.596 (3)	2.62 (3)	2.99 (1)	0.599 (4)
4.0 (5)	0.603 (3)	2.96 (3)	4.25 (1)	0.599 (9)
5.0 (5)	0.600 (1)	5.12 (1)	4.91 (5)	0.599 (9)
6.0 (5)	0.602 (1)	6.50 (1)	6.31 (2)	0.601 (3)