Table 1.

The Young’s modulus from the indentation depth.

h, nm	Group 1, MPa (std)	Group 2, MPa (std)	Group 3, MPa (std)
25	1.95 (0.035)	1.60 (0.027) *	1.71 (0.022) *
50	1.88 (0.046)	1.53 (0.047) *	1.62 (0.038) *
75	1.37 (0.046)	1.40 (0.050) *	1.50 (0.070) *
100	0.94 (0.020)	1.04 (0.183) **	1.22 (0.075) **
125	0.75 (0.035)	0.79 (0.131) **	0.87 (0.029) **
150	0.64 (0.029)	0.70 (0.082) **	0.71 (0.024) **

* p < 0.05, ** p < 0.1.