InP/InGaAs pin-Photodiode Arrays

256 Pages·2008·13.92 MB·English

ETH Library
InP/InGaAs pin-photodiode arrays
for parallel optical interconnects
and monolithic InP/InGaAs pin/
HBT optical receivers for 10-Gb/s
and 40-Gb/s
Doctoral Thesis
Author(s):
Bitter, Martin
Publication date:
2000
Permanent link:
https://doi.org/10.3929/ethz-a-004147994
Rights / license:
In Copyright - Non-Commercial Use Permitted
This page was generated automatically upon download from the ETH Zurich Research Collection.
For more information, please consult the Terms of use.
DISS. ETH No. 13948
InP/InGaAs pin-Photodiode Arrays
for Parallel Optical Interconnects
and
Monolithic InP/InGaAs pin/HBT Optical
Receivers for 10-Gb/s and 40-Gb/s
A dissertation submitted to the
SWISS FEDERAL INSTITUTE OF TECHNOLOGY ZUERICH
for the degree of
Doctor of Technical Sciences
presented by
Martin Bitter
Dipl. El.-Ing. ETH-Z
bom January 17, 1967
citizen of4323 Wallbach, Switzerland
Accepted on the recommendation of
Prof. Dr. Hans Melchior, examiner
Prof. Dr. Heinz Jäckel. co-examiner
November 2000
n
Where will it end? Thirty years ago, it was
impossible to predict what today we take
for granted. History has clearly demonstrat¬
ed that as long scientists and engineers
around the globe continue to invent the
technology to transmit information at a
lower cost per bit, creative people will find
a reason to send proportionally more bits.
This cycle is the driving force that will en¬
sure a future full of light.
Donald B. Kecka
a' Donald B. Keck is vice president and technology director ofOptical Physics at Coming Inc.,
NY. He is co-inventor of the low-loss silica-glass Optical fiber back in 1970. The above
mentioned citation can be found in [KEC00].

TABLE OF CONTENTS
ABSTRACT
KURZFASSUNG
INTRODUCTION 5
I-1 Short Overview of Lightwave Communication Systems 5
1-2 Subject ofthis Thesis 8
1-3 Parallel Optical Interconnects 8
1-4 Monolithic InP/InGaAs pin/HBT Optical Receiver Front-End Modules 9
1-5 Organization of this Thesis 11
PART 1 InP/InGaAs PIN-PHOTODIODE ARRAYS FOR PARALLEL
OPTICAL INTERCONNECTS 13
Chapter 1 Top-Illuminated InPAnGaAs Mesa pin-Photodiodes 15
1-1 Introduction 15
1-2 Design of Top-Illuminated InP/InGaAs Mesa pin-Photodiodes 1 8
1-3 Electrical Characteristics of InP/InGaAs Mesa pin-Photodiodes 19
1-4 Responsiviry and Quantum Efficiency 24
1-5 Speed of Response 30
Chapter 2 Fabrication and Characterization of InP/InGaAs
pin-Photodiodes for Optical Interconnects 41
2-1 Introduction 41
2-2 Design of InP/InGaAs Pin-Photodiode Arrays for Optical Interconnects 44
2-3 Fabrication 48
2-4 Electrical and Optical Characterization 52
2-5 Discussion of Impact of Fabrication Process on Device Performance 60
2-6 Conclusions 66
V
VI TABLE OF CONTENTS
PART 11 MONOLITHIC InP/InGaAs PIN/HBT OPTICAL RECEIVERS
FOR 10-Gb/s AND 40-Gb/s 67
Chapter 3 Monolithic InP/InGaAs pin/HBT Technology for
Optical Receivers 69
3- 1 Introduction 69
3-2 Monolithic InP/InGaAs pin/HBT Technology 72
3-3 Monolithic Photodiodes for Improved Optical Receiver Sensitivity 93
3-4 Conclusions 96
Chapter 4 Design of High Performance 10-Gb/s Optical Receiver
Front-Ends 97
4-1 Introduction and Overview of General Design Considerations 97
4-2 Design of Transimpedance Amplifiers with CE-CC Input-Stages 103
4-3 Layout and Mounting Considerations 118
4-4 Conclusions 121
Chapter 5 Highly-Sensitive 10-Gb/s Optical Receiver
Front-End Modules 123
5- 1 Introduction 123
5-2 CE-A: Single-Ended Receiver 125
5-3 CE-B: Single-Ended Receiver with Improved Optical Overload 137
5-4 CE-C: Single-Ended Receiver with Power-Supply Voltage of 3.3V 139
5-5 CE-D: Fully-Differential Receiver 141
5-6 Conclusions 148
Chapter 6 Design and Implementation of Broadband Optical
Receiver Modules Operating up to 40-Gb/s 151
6- 1 Introduction 151
6-2 Broadband Amplifier Design Considerations 153
6-3 Resistive Darlington Feedback Amplifiers 155
6-4 Darlington Feedback Amplifier Optical Receiver Front-End for 40Gb/s 161
6-5 Optical Receiver with Modified Darlington Feedback Amplifier 172
6-6 Conclusions 177
TABLE OF CONTENTS VH
CONCLUSIONS AND FUTURE DIRECTIONS 179
APPENDICES 185
Appendix A Properties of Relevant Materials for InP/InGaAs Photodetectors
and InP-HBT Optical Receivers 187
Appendix B Calculation And Measurement of Receiver Noise For Sensitivity
Estimation 191
Appendix C Mounting and Packaging Technology for Optical Receiver
Modules 203
Appendix D Thin-Film Bias-Tee Mounting Substrate Technology 215
Appendix E Frequency Response Measurement of Photodetectors and
Optical Receivers Utilizing Second-Harmonic Generation
in MZI-Modulators 223
REFERENCES 227
ACKNOWLEDGEMENTS 247
CURRICULUM VITAE 249
PUBLICATION LIST 251
ABSTRACT
Optical receiver front-end modules are key components in every lightwave communi¬
cation system. They are used for the conversion ofmodulated Optical power into elec¬
trical voltage signals for further processing in subsequent data regeneration circuits. To
keep step with the steadily increasing demand for transmission bandwidth, the devel¬
opment of devices capable of handling data-rates of lOGb/s and even 40Gb/s is of
prime importance. Simultaneously, parallel Optical interconnects become more and
more important for interfacing telecom equipment such as digital routers or cross-con¬
nects because they offer large data pay-loads at a low cost per bit.
As a contribution to high throughput parallel Optical interconnects, we have developed
and fabricated top-illuminated 1x12 InP/InGaAs mesa pin-photodiode arrays for use as
Optical-to-electrical converters in receiver assemblies. The pin-photodiodes with a di¬
ameter oflight-sensitive area of 70jLim obtained a responsivity of 0.85A/W and a band¬
width of 4GHz in a 50Q setup at a wavelength of 1300nm. In combination with a
silicon bipolar 1x12 receiver amplifier array, a total data-throughput of up to 30Gb/s
was achieved.
As a contribution to the advancement ofhigh bit-rate Optical communication, we have
developed fully-packaged Optical receiver front-end modules for direct application in
SDH/SONET systems. To do so, the developed optical receiver circuits were incorpo¬
rated into metal housings with electrical connectors and attached Single-mode silica
fibers for light coupling. Special emphasis was set on the development of an assembly
technique capable of handling electrical high-speed signals. The monolithically inte¬
grated Optical receiver circuits (photodetector/electrical preamplifier combination)
were realized with an InP/InGaAs pin-photodiode/single-heterojunction bipolar tran¬
sistor (pin/HBT) fabrication technology. The top-illuminated monolithic pin-photodi¬
odes were formed with the base-collector epitaxial layer structure of a heterojunction
bipolar transistor device and obtained a responsivity of 0.53A/W and a bandwidth in
excess of 30GHz measured in a 50£1 setup at a wavelength of 1553nm. The bipolar
transistors obtained a maximum current gain rut-off frequency fj of 70GHz and a
small-signal current gain hfe of 20. Optical receiver modules containing pin/HBT re¬
ceiver chips optimized for low-noise Performance achieved state-of-the-art sensitivity
values for pin-photodiode based implementations as low as -20dBm at a data-rate of
lOGb/s and a wavelength of 1553nm.
A broadband Optical receiver module with a bandwidth of 30GHz obtained clear eye
opening at 40Gb/s with a sensitivity better than -lOdBm at a wavelength of 1553nm.
1
2 ABSTRACT
To the best of our knowledge, this result represents the first demonstration of a 40Gb/s
Optical receiver module assembled with a monolithic pin/HBT receiver circuit.