1. Diffractive Optical Element
Design Tools and
Fabrication Process
Kyunghwan Oh,
Department of Physics
Yonsei University

2. Contents
Available DOE design CAD
- DECAD
- DOE-CAD-W
- DiffacMOD
- Optis
- VirtualLab
2. DOE Fabrication Process
- Jena Photonics Fabrication Network (JPFN)
- Institute of Applied Physics, Fredrich Schiller U.

3. Available DOE design CAD
More than 6 commercially available CADs
- DECAD
- DOE-CAD-W
- DiffacMOD
- Optis
- VirtualLab
Probably VirtualLab might be
the most recent and and most efficient one.

4. Available DOE design CAD
DECAD
Free Download
Latest Version 2.44, May
Linux OS
Used by Samsung, Sony, Toshiba
Chalmers University e-beam writter file format only.
Other output file formats will be added
“DECAD ( Diffractive Element Computer Assisted Design ) is a powerful and versatile software developed by Dr. Olivier MAGNIN for diffractive optics design. DECAD both allows synthesis of diffracting phase functions and accurate simulation of their performances. The simulation engine relies on various selectable propagators (Angular Spectrum, Rayleigh-Sommerfeld, Kirchhoff,... ) that are used by the designer for in-depth analysis of the light diffracted by the DOE aperture.”

5. Available DOE design CAD
DECAD
Gaussian to Flat-Top
Analytic Phase Function

6. Available DOE design CAD
DECAD

7. Available DOE design CAD
DECAD
Simulation of Diffraction including High Orders
Investigation of Fabrication Tolerance

8. Available DOE design CAD
DECAD
Master fabricated by e-beam lithography

9. Available DOE design CAD
DECAD
Experimental Assessment

10. Available DOE design CAD
DOE-CAD-W
HOLO/OR makes DOE as well as DOE-CAD-W
MS-Window based
One of earliest pioneer
Compatible to Optics Tool, Zemax, Oslo, CodeV,
along with various outputs
“DOE-CAD for windows, masks generation and performance modeling, for diffractive optical elements
DOE-CAD-W is a software package designed to transform phase function specified by
user into the set of mask files for generating multi-level or gray level DOEs.”

11. Available DOE design CAD
DOE-CAD-W

12. Available DOE design CAD
DOE-CAD-W
Functions available in DOE-CAD-W
Mask files in industrial formats: GDS-II, PostScript, Linework, Bitmap
Mask preview with zoom and cursor
Multiplication of DOE into array of elements with 100% full field factor
Generation of off-center part of the DOE-mask.
Numerical simulation of focal intensity distribution
Estimation of efficiency, accuracy of DOE performance

13. Available DOE design CAD
DOE-CAD-W
Functional advantages
· 2-D nonsymmetrical DOEs supported
· Computer simulation of DOE performance
· Simulation pictures in standard TIFF image format
Production management advantages
· Mask files placed at any directory on hard disk
· Production management support: printing of
production form with overview of all DOE
specification, with date, serial number, model, quantity etc.
· Inventory of DOE masks inputs.

14. Available DOE design CAD
DiffacMOD
A module of Optical Simulation Package,
Rsoft Passive Device Suite
DiffractMOD™ is a general design and simulation tool for diffractive optical structures such as diffractive optical elements, subwavelength periodic structures, and photonic bandgap crystals. It is based on the Rigorous Coupled Wave Analysis (RCWA) technique which has been implemented using advanced algorithms including fast Fourier factorization and generalized transmission line formulation.
Already a market leader, the tool has extensive applications in a broad range of areas including semiconductor manufacturing and wave optics.

15. Available DOE design CAD
DiffacMOD

16. Available DOE design CAD
Optis
LSP lab from the University of Strasbourg, France,
Gerchberg-Saxton algorithm.
Bitmap Image input/output
demo evaluation version or quotation :
“There are a lot of DOE simulation tools, but every feature developed in DOEs simulation tool as been though with tolerancing issues in mind. As a consequence, the final purpose of DOEs simulation tool is to allow every even unskilled user to see the evolution of the reconstructed image quality when changing source or DOE parameters.”

17. Available DOE design CAD
Optis
Step 1 : just define you laser beam
Step 2 : define your target with a BMP editor software
Step 3 : choose DOE parameters you want to build : sampling, number of phase level, near
field or far field optimization
Step 4 : just press « Start » to see the evolution of your result during the optimization. It will
automatically stop when finished
Step 5 : here is your result : you can see quality, uniformity of the generated DOE, and you
obtain a file that represents it: each pixel value (gray level) corresponds to a phase level.
This result can be exported as a bitmap or a formatted text file for industrial manufacturing.

18. Available DOE design CAD
Optis

19. Available DOE design CAD
VirtualLab
Jena, Germany
Version 3.0 October
General Optical Simulation CAD including DOE
Institute of Applied Physics, Fredrich Schiller University
Fraunhofer Institute of Applied Optics
Fabrication service available by
Jena Photonics Fabrication Network™

20. Available DOE design CAD
VirtualLab
VirtualLab™ - Your Benefit
The electromagnetic field kernel and the generalized spread sheet concept Flexopas™ constitute the fundament of VirtualLab™.
Your most essential benefits can be stated in:
Light Source Models
Definition of System Quality Measures
Adjustment of Field Propagation Techniques
Rapid System Investigation
Wave-Optical Design

22. Available DOE design CAD
VirtualLab
Two Movies for DOE Design

23. DOE Fabrication Process

24. DOE Fabrication Process

25. DOE Fabrication Process

26. DOE Fabrication Process

27. DOE Fabrication Process

28. DOE Fabrication Process

29. DOE Fabrication Process

30. DOE Fabrication Process

31. DOE Fabrication Process

32. DOE Fabrication Process

33. DOE Fabrication Process

34. DOE Fabrication Process

35. DOE Fabrication Process

36. DOE Fabrication Process

37. DOE Fabrication Process

38. Hot Embossing Microfabrication
Hot Embossing is a technique of imprinting microstructures on a substrate (polymer) using a master mold (silicon tool).

39. Steps in Hot Embossing
Heating Silicon & Polymer above glass transition temperature (Tg).
Applying load by pressing the silicon tool on polymer at certain embossing pressure.
Cooling the silicon tool and polymer assembly below Tg and de-embossing the tool.
Master/Mold
from Femto-
Second Laser
Heat the substrate
and mold to just
above Tg of the
substrate
Apply embossing
force on the
substrate via the
mold under vacuum
Cool the
below Tg
De-embossing
of the mold and

40. Advantages of Hot Embossing System
Cost effective – Easy manufacturability.
Time efficient – Fast process.
Fabrication of high aspect ratio features.
Bio-Compatible surfaces – Polymer substrates used.
Disposable – Low cost for volume production.

41. Applications of Hot Embossing
BioMEMS/Bio-Sensors
Micro-Fluidic Devices
Micro-Optics
m-TAS (Micro Total Analysis Systems)

42. Hot Embossing v/s Other MEMS Fabrication Processes
Characteristics
LIGA
Surface Micro-machining
Hot Embossing
Number of layers 1
3-5
Minimum feature size
5 microns
1 micron
Aspect ratio 20
N/A 10
Cost
High
Moderate
Low
Productivity
Residual Stress
Very Low

43. Schematic Representation of Hot Embossing Setup

44. Hot Embossing Conceptual Solid Models

45. Mini-Vacuum Chamber
Mini vacuum chamber used to provide a clean and moisture free environment during embossing.
Mini vacuum chamber can accommodate an 8” substrate.