Development of corrugated thin metal structures for a MEMS-based fiber optic aligner

148 Pages·2015·4.06 MB·English

by  Jason Todd Iceman

Lehigh University
Lehigh Preserve
Theses and Dissertations
2006
Development of corrugated thin metal structures
for a MEMS-based fiber optic aligner
Jason Todd Iceman
Lehigh University
Follow this and additional works at:http://preserve.lehigh.edu/etd
Recommended Citation
Iceman, Jason Todd, "Development of corrugated thin metal structures for a MEMS-based fiber optic aligner" (2006).Theses and
Dissertations.Paper 939.
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Iceman, Jason
Todd
Development of
Corrugated Thin
Metal Structures
for a MEMS
based Fiber Optic
Aligner
May 2006
Development of
Corrugated Thin Metal
Structures for a MEMS-based
Fiber Optic Aligner
Jason Todd Iceman
Presented to the Graduate and Research Committee
ofLehigh University
in fulfillment ofthe
thesis requirement for the degree of
MasterofScience
m
Materials Science and Engineering
Lehigh University
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Acknowledgements
Iam indebted to Professor Ray Pearson for allowing me the opportunity to work on this
project. Several other faculty and staffhave been a part ofthe research team investigating the
fiberoptic aligner. Their help has been invaluable. Professors Rick Vinci, Svetlana Tatic-Lucic
and Walter Brown have provided guidance and constructive advice throughout the course ofthis
work. Seungmin Hyun and Weisong Wang provided assistance with SEM imagery and
modeling. Mehmet Sahin, Murat Ozturk and Professor Herman Nied developed the closed form
solution for the bucking ofa corrugated thin film structure. Mike Rogosky and John Mcintosh at
the Penn State University Nanofab were instrumental in the development of the grayscale
lithography work described in this thesis. Dr. Amir A. Saghiri ofHeidebcrg Instuments provided
greyscale lithography samplesand developmenttime to this project.
On a more personal note, Iwould also liketo thank W. Jeffrey Shakespeare, Ph.D. for his
unflagging support and enthusiasm without which Iwould not have had the courage to begin the
journey toward an advanced degree. My spouse, Lena Marie Iceman, and children Benjamin
Ryan Iceman and Sarah Elizabeth Iceman gave willingly oftheir time and love throughout the
research and writingrequired to completethis thesis.
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Table of Contents
Acknowledgements iii
TableofContents iv
ListofTables vi
ListofFigures vii
Abstract x
Chapter I Introduction I
I.I Purpose ofstudy I
1.2 Target Problem Description 2
1.3 The Solution 3
1.4 Overview ofthe Thesis 4
Chapter2Background 5
2.I Electrical versusoptical interconnects 5
2.2 Macroscopic Alignment Technologies 7
2.3 MEMS-based AlignmentTechnologies 12
Chapter3Engineeringofthe In-Package-Micro-Aligner 24
3.1 Device dimensions and materials 24
3.2 Device Operation 28
3.3 Possible Process Sequence 33
3.4 Device performance 36
Chapter4Novel design ofamicro-aligner 42
4.1 Refiningthe BoeingIPMA design 42
4.2 Concept for thin film based alignerwith integrated lockingmechanism .46
Chapter 5Fabrication and TestingofCorrugated Structures 51
5.1 Embossingacorrugatedthin film structurc 51
5.1.1 Fabrication oftools 52
5.1.2 Substrate infomlation 57
5.1.3 Embossingmethodology 58
IV
5.1.4 Metal depositionand imagingofembossed structures 63
5.2 Usinggrayscale lithographyto create3D structures 68
5.2.1 Grayscale substrate infonnation 69
5.2.2 Maskdesign and greyscale resistfabrication 70
5.2.3 Metal deposition and imagingofgrayscale structures 74
5.3 Testingresults ofcorrugated thin film structures 81
5.3.1 Design oftestingapparatus 81
5.3.2Testingprocedure 87
5.4 Results 91
5.5 Analysis and discussion 92
Chapter6Conclusions, Suggestions for FurtherResearch and References Cited 95
6.1 Summary 95
6.2 Suggestions for further research 95
6.3 References Cited 99
Appendix ALoad Cell Calibration l02
List of Tables
Table I -OverviewofMEMS optical alignmenttechnologies 13
Table2-Shipley 220-7 softbake schedule 70
Table 3-Polishingsteps for XC samplepreparation 74
Table 4-Area moment ofinertiafor samplestested 91
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List of Figures
Figure I -Awirebondingmachine makinghigh density interconnects 6
Figure 2-Alignmentoftwo optical waveguides4 8
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
Figure 3-Cross section ofconceptual optoelectronic transmitter package 9
Figure 4-A lensed fiber5••........••••.•...•.•..•.••.•••..•.••.....•.•..•.••.•••.••..•••....••••.•...••....•••....•.••...•.••••.•••..•.10
Figure 5-Power loss dueto misalignment5 10
Figure 6-Microlens aligned to optical fiber 11
Figure 7-Lateral toleranceofmicrolensalignment 11
Figure 8-Angulartoleranceofmicrolensalignment 12
Figure9- IPMA Alignerconceptl3 15
Figure 10-Electrostatic fiber alignmentdevice9 16
Figure II - Piezoelectricactuatorconceptl2 17
Figure 12- Thermoelectric actuatorsI5 18
Figure 13 -U-Shaped cantileveractuators17 19
Figure 14 -Silicon Micro XY stage20 20
Figure 15 -IlIustrationoflatchingoptical platforml5 21
Figure 16 -Detail oflatching mechanismI5 21
Figure 17 - Polymeractuatorconcept29 22
Figure 18 -XY stagedriven by polymeractuators29 22
Figure 19-SEM Picture ofadevice 24
Figure 20 -X-axis actuator 25
Figure 21 -Actuatordetail 25
Figure 22 - Plan vie\v ofactuator 26
Figure 23 - Heateretch detail 27
Figure 24 -Mask data 27
Figure 25 -IP~1A and franle 29
Figure 26 -IMPA compliant spring 29
Figure 27 - Diode and locking mechanism 30
Figure 28 - X. ''1' and Zactuators 30
Figure 29 -Unbiased actuator 31
Figure 30- Biasedactuator 31
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Figure 31 -Cross sectionofbimorph .32
Figure 32 - Deflected bimorph 32
Figure 33 - Process sequence .34
Figure 34 - Process sequence (cont'd) .35
Figure 35 -Displacement response .38
Figure 36 -Voltage response .39
Figure 37 - Force vs. displacement, measured and modeled .40
Figure 38 - Actuatormodeled in ANSYS 41
Figure 39 -Conceptual image ofcross section ofcorrugated structures .45
Figure 40 -Conceptual image ofisometric view ofacorrugated structure .45
Figure 41 - Plan viewofinchworm drive .46
Figure42 -Thecorrugated beams used in the inchworm drive .48
Figure 43 -Conceptual motion ofinchworm drive .49
Figure 44 -Concept image ofembossing process 52
Figure 45 -Machined mandrel print... 53
Figure46 -Top viewofwire-wound mandrel 54
Figure47 -Profileview ofwire-wound mandrel.. 54
Figure48 -Photo ofmandrel windingtool 55
Figure49 -Block diagram ofmandrel winding tool... 56
Figure 50 - Photoofmandrel duringwinding 57
Figure 51 -PhotoofBridgeport milling machine used for mechanicalembossing 59
Figure 52 -Conceptual diagram ofembossingfixturing 60
Figure 53 -Photo ofembossingfixturing 60
Figure 54 -Samples afterembossing 62
Figure 55 -Microscopic view ofembossed sample 63
Figure 56- Mask on top ofcorrugations 64
Figure 57 - After metal deposition 64
Figure 58 -Optical micrograph ofembossed sample afterdeposition 65
Figure 59- Cross-section ofembossed structure 66
Figure 60 -Micrograph data importedto CAD 66
Figure 61 - Lower magSEM Image ofembossedstructure 67
Figure 62 - Higher mag SEM imageofembossed structure 61\
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