This document discusses using atomic layer deposition to apply conformal optical coatings to complex 3D structures. Traditional optical coating methods have limitations in achieving conformality. The author details experiments applying tantalum pentoxide coatings to hemispherical domes using an ALD system. Thickness measurements show uniformity of less than 2% across the domes. Additional examples apply antireflective coatings and summarize results for 13 coating processes. The document promotes further discussion at a poster and booth during a conference.

1. Conformal optical coatings on
complex 3D-macrostructures
using atomic layer deposition
D.Sc. John Rönn
Advanced ALD, Beneq Oy
Paper: TC.4
john.ronn@beneq.com

2. 8/18/2022
Motivation
 Optics and optical sciences are widely used in everyday life
 Production of optical coatings is well-established with traditional fabrication technologies
 Low cost
 Low temperature
 High throughput
 Excellent uniformity

3. 8/18/2022
Motivation
 Optics and optical sciences are widely used in everyday life
 Production of optical coatings is well-established with traditional fabrication technologies
 Low cost
 Low temperature
 High throughput
 Excellent uniformity
 Conformality

4. 8/18/2022
Motivation
 Optics and optical sciences are widely used in everyday life
 Production of optical coatings is well-established with traditional fabrication technologies
 Low cost
 Low temperature
 High throughput
 Excellent uniformity
 Conformality

5. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Film growth studies on 3D-macrostructures
 Setup: P400A, 2x Monitor Hemispherical Domes, 1x Dummy Dome
150 mm

6. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Film growth studies on 3D-macrostructures
 Setup: P400A, 2x Monitor Hemispherical Domes, 1x Dummy Dome

7. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Film growth studies on 3D-macrostructures
 Setup: P400A, 2x Monitor Hemispherical Domes, 1x Dummy Dome

8. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Example: Ta2O5 at 150 °C

9. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Example: Ta2O5 at 150 °C
• Upper Dome

10. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Example: Ta2O5 at 150 °C
• Upper Dome
49.84
50.35
50.33
49.82
49.82 49.62
49.86
50.11
49.09
50.29
 Units [nm]
 Thickness non-uniformity 1.26 %

11. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Example: Ta2O5 at 150 °C
• Middle Dome

12. 8/18/2022
Conformal Optical Coatings with Beneq ALD
 Example: Ta2O5 at 150 °C
• Middle Dome
50.35
51.02
51.20
49.94
50.33 50.18
50.29
50.52
49.82
50.70
 Thickness non-uniformity 1.37 %
 Batch non-uniformity 2.10 %
 Units [nm]

13. 8/18/2022
 Summary of 13 developed processes
Conformal Optical Coatings with Beneq ALD
(𝐿max − 𝐿min)/2𝐿ave

14. 8/18/2022
 Anti-Reflective Coating on Fused Silica
• Nb2O5-SiO2 at 300 °C
• Central wavelength: 905 nm (e.g., for LIDAR applications)
Conformal Optical Coatings with Beneq ALD
• D2 = Middle Dome
• D3 = Upper Dome
• CX = Convex Side
• CV = Concave Side
AOI: 10°
2 3
4
5
1

15. 8/18/2022
 Anti-Reflective Coating on Fused Silica
• Nb2O5-SiO2 at 300 °C
• Central wavelength: 905 nm (e.g., for LIDAR applications)
Conformal Optical Coatings with Beneq ALD
AOI: 20°
• D2 = Middle Dome
• D3 = Upper Dome
• CX = Convex Side
• CV = Concave Side
2 3
4
5
1

16. 8/18/2022
 Anti-Reflective Coating on Fused Silica
• Nb2O5-SiO2 at 300 °C
• Central wavelength: 905 nm (e.g., for LIDAR applications)
Conformal Optical Coatings with Beneq ALD
AOI: 30°
• D2 = Middle Dome
• D3 = Upper Dome
• CX = Convex Side
• CV = Concave Side
2 3
4
5
1

17. 8/18/2022
Meet us
 See our poster TC.4
 Visit us at our booth #123

18. Beneq® is a leading supplier of production and research equipment for atomic layer deposition
(ALD), a provider of thin film coating services, and the world’s premier manufacturer of thin
film electroluminescent (TFEL and TASEL) displays.
www.beneq.com | www.lumineq.com
Tel. +358 9 7599 530
info@beneq.com | lumineq@beneq.com
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