Etching time

(min)

Removed thickness

(μm)

Bulk etch rate

(μm/h)

80

3.85 ± 0.23

2.85 ± 0.17

85

4.22 ± 0.30

2.97 ± 0.21

90

4.37 ± 0.29

2.91 ± 0.19

95

5.16 ± 0.33

3.27 ± 0.21

100

5.17 ± 0.38

3.10 ± 0.23

105

5.88 ± 0.44

3.36 ± 0.25

110

6.22 ± 0.40

3.39 ± 0.22

115

6.80 ± 0.44

3.54 ± 0.23

120

6.68 ± 0.42

3.34 ± 0.21

125

6.78 ± 0.44

3.26 ± 0.21

130

7.12 ± 0.54

3.28 ± 0.25

135

7.39 ± 0.47

3.28 ± 0.21