Sample

RMS (nm)

R_a (nm)

R_max (nm)

Al₂O₃

1.68

1.37

11.3

AHO[1/1]

2.16

1.71

16.9

AHO[1/2]

3.59

2.78

32.9

AHO[1/3]

4.78

3.94

29.1

AHO[1/4]

5.61

4.64

33.7

HfO₂

7.45

5.46

58.3