Fabrication of Anti-reflection Film with Sub- wavelength Structures Using Roll-to-Roll imprinting...

Fabrication of Anti-reflection Film with Sub-wavelength Structures Using Roll-to-Roll imprinting

Reporter Po-Hsiang Wang﹕ (王柏翔 )Advisor ： Deng-Maw LU (盧燈茂 ) Cheng-Hsin Chuang (莊承鑫 )

Department of Mechanical Engineering, Southern Taiwan University of Science and Technology, Tainan, Taiwan

Date: 2015/05/13

運用滾對滾轉印技術製作具次波長結構之抗反射膜

Outline

2

Introduction

Experimental setup and results

Anti-reflection film measurement

Conclusions

Porous Anodic Alumina Oxide (AAO) Template

R2R Nanoimprinting process

The transmittance and reflectance measurement results

Motivation

Types of Anti-reflection film

Outline

3

Introduction



Conclusions




Motivation


4

Motivation

Reflection

Low contrast

Low contrastDecreased conversion efficiency

Low transmittance

Disadvantages of light reflection

n=1.5

Air n=1 Air n=1

n=1.5

n=1.1~1.4

10%

5

Antireflective coating technology – Multilayer coating

Antireflective structure – Sub-wavelength structure

(SWSs)

Protective filmAntireflection

layerSubstrate with

hard coatingAdhesive layer

SeparatorThe refractive index of multilayer (Ladder)

High-cost facilities


6


Antireflective structure - Sub-wavelength structure (SWSs) Moth eye structures

The reflective index of cylindrical SWSsThe reflective index of cone-shape SWSs

Information source : FINETECH JAPAN 2011

Multilayer coating

The lowest reflection and broadband

Sub-wavelength Structures(SWSs)

The best optical characteristicNanoImprinting processLow-cost

How to achieve broadband and omnidirectional antireflection with low cost

process?

7

Types of Sub-wavelength structures (SWSs)SWSs

AAO Template

Traditional Homemade

Disadvantages• Complex• High-end facilities• Costly• Small size

Advantages Low-cost nano- scale mold Simple process The best optical characteristic Large area

book edited by Xihong Peng, ISBN 978-953-51-0898-6,

Published: December 19, 2012 under CC BY 3.0 license

http://creativecommons.org/licenses/by/3.0/

Outline

8

Introduction



Conclusions




Motivation


9

Idea of Fabricating the Sub-wavelength Structures(SWSs)

Anodization Aluminum Oxide (AAO) Technique

R2R UV curing process Anti-reflection (AR) film

Mold fabrication

Fabrication

Pattern transformation Optical measurement

9

Nano imprinting lithography

10

Experimental setup – Large area anodization process

Facilities for anodization

Advantages

Maintain at the low temperature state

Large area AAO template can be

done

O

I 40V 1A

DC Power supply

11

Experimental – Fabrication of AAO template

Procedures

Pure aluminum substrate

1st anodization process

Removed anodic oxide layer by acid

2nd anodization process

1st anodization process

Applied voltage(V)

Electrolyte (Oxalic acid)

Time(min)

Temperature( )℃

40 0.3M 30 4

2nd anodization process

Applied voltage(V)

Electrolyte(Oxalic acid)

Temperature( )℃

Widening time(min)

40 0.3M 32 10

Anodizing + etchig = 1 time (1st cycle)

Anodizing + etchig = 1 time (2nd cycle)

12

Experimental result – Different 2nd anodization time Top view Widening time 10min, repetition times N=5

Cross section view 297

mm

Ø90 mm

Experimental result – Different 2nd widening time

10min 10、 8、 6、 4、 2min

Outline

14

Introduction



Conclusions




Motivation


Experimental process – R2R Nanoimprinting process

Roll to roll for replicating sub-wavelength on PET

UV light

AAOtemplat

e

Strain Control System

Scraper

Coating system

PET film

UV resin

Pre-heat system

SWSs

Outline

16

Introduction



Conclusions




Motivation


17

Optical measurements results – Transmittance (%)

Transmittance and of the PET plate with/without SWSs

SWSs (aspect ratio 1:2.2)

89%

92%

SWSs (aspect ratio 1:1)

SWSs (aspect ratio 1:0.5)

18

Optical measurements results – Reflectance (%)

Reflectance and of the PET with/without the SWSs

1%

5%4.2%

4.6%

Incident light angles

4.2% 4.2%

6.4%

Outline

19

Introduction



Conclusions




Motivation


20

Conclusions

本實驗成功利用不同的陽極處理時間及擴孔時間循環得到不同深款比的尖錐狀孔洞之陽極氧化鋁模板。

成功控制不同擴孔時間製作具多孔性尖錐狀陽極氧化鋁模板。

成功利用低成本的奈米滾印技術製作大面積具次波長之抗反射光學膜。

此抗反射光學膜穿透率有效提升 3%;反射率從 5%下降至1%。

未來將完成高純度鋁靶材滾筒製作具次波長結構之抗反射光學膜及使用 H-PDMS製做抗反射玻璃。

21

Thanks for your attention !!

STUST

[email protected]

Fabrication of Anti-reflection Film with Sub- wavelength Structures Using Roll-to-Roll imprinting...

Documents

Transcript of Fabrication of Anti-reflection Film with Sub- wavelength Structures Using Roll-to-Roll imprinting...