Is he ever going to quit? 1 High power, high speed and high - - PowerPoint PPT Presentation

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Is he ever going to quit?

High power, high speed and high linearity photodiode for NextGen-VLA antenna project

Qinglong Li, Andreas Beling, Joe C. Campbell

University of Virginia, Charlottesville, VA 22904

• High power photodiode in analog link
• Normal incidence high power photodiode
• 3 bands: 10 ~ 40 GHz, 40 ~ 65 GHz, 75 ~ 110 GHz
• Evanescently coupled waveguide photodiode
• High linearity photodiode
• Summary

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Outline

Photodiode

Solar cell Laser or LED diode Photodetector

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• Signal transmission

– Video distribution in CATV – Antennas – Radio-over-Fiber (RoF) for wireless communication

Analog optic link

• Signal processing

– MMW/THz signal generation – Optical beam-forming network in phased array radar

Our Research interests

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Why high power?

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Link gain Spurious-free dynamic range Noise figure

Photocurrent

Link gain Spurious-free dynamic range Noise figure

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Photodiode Saturation Behavior

• High carrier concentration in

depletion region

• E-field collapses
• Carrier transport disrupted
• RF output power compressed

Carrier distribution Electric field collapse

Space charge effect

Carrier velocities

Thermal effect

Heat sink Layer parameters Bias voltage

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Photodiode Speed

• High Speed

– Carrier transit time

• Reduce carrier travel distance

– RC time constant

• Smaller device surface area
• Thicker device depletion region
• Introduce an inductor (high impedance transmission line)

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hν P N

Transit time

Photodiode model Rp Cpd Rs Iphoto L Z0 >> ZL ZL

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Uni-Traveling Carrier (UTC) Photodiodes

Vdrift,e

PIN UTC

Ishibashi etal (IEICE Trans. Electron. 2000)

• P+ absorber + transparent

collection I-layer

• Quasi-field accelerates

electron transport

• Holes relax fast within

dielectric relaxation time

• Only electron traveling

benefits bandwidth

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diamond

undepleted InGaAs absorber InP drift layer InP cliff layer depleted InGaAs absorber

Charge-Compensated Modified UTC with “Cliff” Layer

• 1. Charge compensated collector
• 3. “Cliff” layer to maintain high field in depleted

absorber at high current

• 2. Partially depleted absorber
• i. high e-field at heterjunction
• ii. Increase responsivity without sacrificing BW

E

Dark Field High Current Field E Dark Field High Current Field

UTC CC-UTC

• 4. Flip-chip bonding for surface normal PDs

e Absorber Collector “Cliff” layer Transition layers

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Normal Incidence Photodiodes: RF Output Power and Saturation Current versus Frequency

diamond

• 15. X. Wang, et al., IEEE Photon. Technol. Lett., vol. 19, no. 16, pp. 1272–1274,

2007.

• 16. M. Chtioui, et al., IEEE Photon. Technol. Lett., vol. 20, no. 3, pp. 202–204, 2008.
• 17. Z. Li, et al., IEEE J. Quantum Electronics, vol. 46, no. 5, 2010.
• 18. N. Li, et al., IEEE Photon. Technol. Lett., vol. 16, no. 3, pp. 864-866, 2004.
• 19. M. Chtioui, et al., IEEE Photon. Technol. Lett., vol.24, no.4, pp.318-320, 2012.
• 20. X. Xie et al., Optica, vol. 1, no. 6, pp. 429 – 436, 2014.
• 21. Q. Zhou et al., IEEE Photonics Tech. Lett., vol. 25 ,No. 10 , pp. 907-909, 2013.
• 22. Y.-S. Wu et al. 2008
• 9. X. Li, S. Demiguel, et al., Electron. Lett., vol. 39, no. 20, Oct. 2003.
• 10. Z. Li, et al., Proc. 37th Europ. Conf. Optical Commun. (ECOC

2011), Geneva, Switzerland, Sept. 2011.

• 11. N. Duan, et al., 19th Annu. Meeting IEEE Lasers Electro-Optics

Soc.(LEOS 2006), Oct. 2002, pp. 52-53, paper WD2.3.

• 12. K. Sakai, et al., IEEE Trans. Microwave Theory Tech., vol. 58, no.

11, pp. 3154-3160, 2010.

• 13. N. Shimizu, et al., Electron. Lett., vol. 36, no. 8, pp. 750-751, April

2000.

• 14. D. A. Tulchinsky, et al., J. Lightwave Tech.., vol. 26, no. 4, pp. 408-

416, 2008.

Flip-chip bonded MUTC

R = 0.75 A/W R = 0.45 A/W R = 0.17 A/W 9

10 GHz ~ 40 GHz Design

InP, semi-insulating substrate, Double side polished InP, n+, Si, 1.0x1019, 900nm InP, n+, Si, 1.0x1018, 100nm Drift layer InP, n-, Si, 1x1016, 700nm Cliff layer InP, n-, Si, 1.4x1017, 50nm Grading InGaAsP,Q1.1, n-, Si, 1x1016, 15nm Grading InGaAsP, Q1.4, n-, Si, 1x1016, 15nm Depleted absorber InGaAs, n-, Si, 1x1016, 350nm Un-depleted absorber InGaAs, p+, Zn, 5x1017, 250nm Un-depleted absorber InGaAs, p+, Zn, 8x1017, 200nm Un-depleted absorber InGaAs, p+, Zn, 1.2x1018, 150nm Un-depleted absorber InGaAs, p+, Zn, 2x1018, 100nm Grading InGaAsP,Q1.4, p+, Zn, 5x1018, 15nm Grading InGaAsP,Q1.1, p+, Zn, 5x1018, 15nm InP, p+, Zn, 2x1018, 100nm Contact layer InGaAs, p+, Zn, 2x1019, 50nm

• 24-µm diameter MUTC-K device exhibits 40 GHz

bandwidth with inductive peaking

• CPW design: W:30 µm, G: 200 µm, L: 90 µm
• The estimated transit-time bandwidth is 47 GHz (9 ps

transit time).

• Estimated R: 0.97 A/W (with AR coating and top

metal mirror with backside illumination) RC and transit time RC time limited BW

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40 GHz ~ 65 GHz device design

InP, semi-insulating substrate, Double side polished InP, n+, Si, 1.0x1019, 900nm InP, n+, Si, 1.0x1018, 100nm Drift layer InP, n-, Si, 1x1016, 400nm Cliff layer InP, n-, Si, 1.4x1017, 50nm Grading InGaAsP,Q1.1, n-, Si, 1x1016, 15nm Grading InGaAsP, Q1.4, n-, Si, 1x1016, 15nm Depleted absorber InGaAs, n-, Si, 1x1016, 250nm Un-depleted absorber InGaAs, p+, Zn, 8x1017, 150nm Un-depleted absorber InGaAs, p+, Zn, 1.2x1018, 150nm Un-depleted absorber InGaAs, p+, Zn, 2x1018, 100nm Grading InGaAsP,Q1.4, p+, Zn, 5x1018, 15nm Grading InGaAsP,Q1.1, p+, Zn, 5x1018, 15nm InP, p+, Zn, 2x1018, 100nm Contact layer InGaAs, p+, Zn, 2x1019, 50nm

• 18-µm diameter MUTC-V device exhibits 65 GHz

bandwidth with inductive peaking

• CPW design: W:25 µm, G: 220 µm, L: 140 µm
• The estimated transit-time bandwidth is 72 GHz (6 ps

transit time).

• Estimated R: 0.76 A/W (with AR coating and top metal

mirror with backside illumination) RC and transit time RC time limited BW

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75 GHz ~ 110 GHz

• 10-µm diameter MUTC-W device exhibits 110 GHz

bandwidth with inductive peaking

• CPW design: W:30 µm, G: 200 µm, L: 100 µm
• The estimated transit-time bandwidth is 117 GHz (3.8

ps transit time).

• Estimated R: 0.41 A/W (with AR coating and top

metal mirror with backside illumination)

InP, semi-insulating substrate, Double side polished InP, n+, Si, 1.0x1019, 1000nm InP, n+, Si, 1.0x1018, 100nm Drift layer InP, n-, Si, 1x1016, 280nm Cliff layer InP, n-, Si, 3x1017, 30nm Grading InGaAsP,Q1.1, n-, Si, 1x1016, 10nm Grading InGaAsP, Q1.4, n-, Si, 1x1016, 10nm Depleted absorber InGaAs, n-, Si, 1x1016, 150nm Un-depleted absorber InGaAs, p+, Zn, 5x1017, 50nm Un-depleted absorber InGaAs, p+, Zn, 1x1018, 50nm Un-depleted absorber InGaAs, p+, Zn, 2x1018, 50nm Grading InGaAsP,Q1.4, p+, Zn, 2x1018, 10nm Grading InGaAsP,Q1.1, p+, Zn, 2x1018, 10nm InP, p+, Zn, 2x1018, 100nm Contact layer InGaAs, p+, Zn, 2x1019, 50nm

RC and transit time RC time limited BW

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Design Summary

÷ ÷ ø ö ç ç è æ - ´ ÷ ÷ ø ö ç ç è æ + +

• =

wt wt w w w j j R R C j C L I I

S L PD PD total

) exp( 1 ) ( 1 1 ) ( ) (

2

RC Transit time

) 1 )( 1 (

2

thickness

d surface ideal in ph

e R R P I R

a

• =

=

PD size (Φ: µm) Band (GHz) Responsivity (A/W) Projected Isat (mA) Projected PRF (dBm) 24 10 ~ 40 0.97 126 23 @ 40 GHz 18 40 ~ 65 0.76 82 19 @ 65 GHz 10 75 ~ 110 0.41 53 14 @ 110 GHz

Bandwidth estimation: Responsivity estimation:

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Normal Incidence Photodiodes: RF Output Power and Saturation Current versus Frequency

diamond

• 15. X. Wang, et al., IEEE Photon. Technol. Lett., vol. 19, no. 16, pp. 1272–1274,

2007.

• 16. M. Chtioui, et al., IEEE Photon. Technol. Lett., vol. 20, no. 3, pp. 202–204, 2008.
• 17. Z. Li, et al., IEEE J. Quantum Electronics, vol. 46, no. 5, 2010.
• 18. N. Li, et al., IEEE Photon. Technol. Lett., vol. 16, no. 3, pp. 864-866, 2004.
• 19. M. Chtioui, et al., IEEE Photon. Technol. Lett., vol.24, no.4, pp.318-320, 2012.
• 20. X. Xie et al., Optica, vol. 1, no. 6, pp. 429 – 436, 2014.
• 21. Q. Zhou et al., IEEE Photonics Tech. Lett., vol. 25 ,No. 10 , pp. 907-909, 2013.
• 22. Y.-S. Wu et al. 2008
• 9. X. Li, S. Demiguel, et al., Electron. Lett., vol. 39, no. 20, Oct. 2003.
• 10. Z. Li, et al., Proc. 37th Europ. Conf. Optical Commun. (ECOC

2011), Geneva, Switzerland, Sept. 2011.

• 11. N. Duan, et al., 19th Annu. Meeting IEEE Lasers Electro-Optics

Soc.(LEOS 2006), Oct. 2002, pp. 52-53, paper WD2.3.

• 12. K. Sakai, et al., IEEE Trans. Microwave Theory Tech., vol. 58, no.

11, pp. 3154-3160, 2010.

• 13. N. Shimizu, et al., Electron. Lett., vol. 36, no. 8, pp. 750-751, April

2000.

• 14. D. A. Tulchinsky, et al., J. Lightwave Tech.., vol. 26, no. 4, pp. 408-

416, 2008.

Flip-chip bonded MUTC

R = 0.75 A/W R = 0.45 A/W R = 0.17 A/W

0.97 A/W 0.76 A/W 0.41 A/W

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Normal incidence Bandwidth-Efficiency Trade Off

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10 100 1000 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1 2 3

Quantum Efficiency Absorption thickness (µm) Transit time Bandwidth(GHz)

) 1 (

thickness

d i

e

a

h

• =

d v ftr p 2 5 . 3 =

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MUTC Waveguide Photodiodes

Optical Intensity distribution

Evanescently coupled MUTC PD

Optical input

P N WG

Iph

Absorber Drift layer Absorber

WG

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Frequency Response Simulation

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Size (µm2) Responsivity (A/W) Bandwidth (GHz) 24 0.40 129 35 0.48 120 50 0.67 110

63% efficiency improvement compared with surface normal

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Linearity-3rd Order Intermodulation Distortion

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• Fundamental power

Pf: slope =1

• Intermodulation distortion

PIMD3: slope=3

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High Linearity Graded Bandgap Structure

40 μm diameter, 14 V bias MUTC-9 with high, fl

e Absorber Collector “Cliff” layer Transition layers

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MUTC9 MUTC9_R4

High doping: Reduce the self- induced electric field in un- depleted absorption layers and thus lower AM-PM. Increase doping: Enhance the electrical filed.

InP, semi-insulating substrate, Double side polished InP, n+, Si, 1.0x1019, 1000nm InP, n+, Si, 1.0x1018, 100nm Drift layer InP, n-, Si, 1x1016, 400nm Cliff layer InP, n-, Si, 3x1017, 50nm Grading InGaAsP,Q1.1, n-, Si, 1x1016, 15nm Grading InGaAsP, Q1.4, n-, Si, 1x1016, 15nm Un-depleted absorber InGaAs, p+, Zn, 5x1018, 100nm Grading InGaAsP,Q1.4, p+, Zn, 1x1017, 15nm Grading InGaAsP,Q1.1, p+, Zn, 1x1017, 15nm InP, p+, Zn, 1x1018, 100nm Contact layer InGaAs, p+, Zn, 2x1019, 50nm Un-depleted absorber InGaAs, p+, Zn , 5x1018, 100nm Un-depleted absorber InGaAs, p+, Zn , 5x1018, 100nm Depleted absorber InGaAsP, Q 1.58, n-, Si, 3x1016, 120nm Depleted absorber InGaAsP, Q 1.62, n-, Si, 3x1016, 120nm Depleted absorber InGaAs, n-, Si, 3x1016, 80nm

Decrease thickness

InP, semi-insulating substrate, Double side polished InP, n+, Si, 1.0x1019, 1000nm InP, n+, Si, 1.0x1018, 100nm Drift layer InP, n-, Si, 1x1016, 400nm Cliff layer InP, n-, Si, 3x1017, 50nm Grading InGaAsP,Q1.1, n-, Si, 1x1016, 15nm Grading InGaAsP, Q1.4, n-, Si, 1x1016, 15nm Depleted absorber InGaAsP, Q 1.58, n-, Si, 1x1016, 120nm Depleted absorber InGaAsP, Q 1.62, n-, Si, 1x1016, 120nm Depleted absorber InGaAs, n-, Si, 1x1016, 80nm Un-depleted absorber InGaAs, p+, Zn, 5x1017, 200nm Un-depleted absorber InGaAs, p+, Zn, 1x1018, 200nm Grading InGaAsP,Q1.4, p+, Zn, 5x1018, 15nm Grading InGaAsP,Q1.1, p+, Zn, 5x1018, 15nm InP, p+, Zn, 2x1018, 100nm Contact layer InGaAs, p+, Zn, 2x1019, 50nm Un-depleted absorber InGaAs, p+, Zn, 2x1018, 200nm

High Linearity Photodiodes

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MUTC9_R4

High Linearity Photodiodes

Op#mized MUTC9 MUTC9

Op#mized MUTC9 MUTC9

Simulated phase of new MUTC Measured phase of MUTC9 Simulated AM-PM of new MUTC Measured AM-PM of MUTC9

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Summary

• High RF output with optimized normal incidence

MUTC photodiode within 3 bands

• 23 dBm @ 40 GHz, 19 dBm @ 65 and 14 dBm @ 110

GHz expected

• Higher responsivity with MUTC waveguide

photodiode design

• Modified MUTC design expected to improve

linearity

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Thank you! Q/A

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