1 / 17

Si WDM Modulator Array for FWH-OCDMA

OCDMA Review April 6 th , 2005. Si WDM Modulator Array for FWH-OCDMA. Sagi Mathai, Xin Sun Prof. Tsu-Jae King, Prof. Ming C. Wu EECS Department University of California, Berkeley. FWH-OCDMA All Si Transmitter. Wavelength Selective Microring Modulator Array. Multi-Wavelength Source Input.

carlucci
Download Presentation

Si WDM Modulator Array for FWH-OCDMA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. OCDMA Review April 6th, 2005 Si WDM Modulator Arrayfor FWH-OCDMA Sagi Mathai, Xin SunProf. Tsu-Jae King, Prof. Ming C. Wu EECS DepartmentUniversity of California, Berkeley

  2. FWH-OCDMA All Si Transmitter Wavelength Selective Microring Modulator Array Multi-Wavelength Source Input Encoded Output Drop Ports for Feedback Control

  3. Free-Carrier Plasma Effect Absorption Coefficient Change Refractive Index Change Holes Holes -n  (cm-1) Electrons Electrons Carrier Concentration (cm-3) Carrier Concentration (cm-3) Ref: Irace, et.al., Silicon Photonics, Topics in Appl Phys, vol 94, pp 361-392, 2004.

  4. Modulation Mechanism SCHEMATIC (TOP VIEW) OPTICAL FREQUENCY RESPONSE si st Modulated Output |st/si|2 n0 n=0  0 sd • Index of refraction can be tuned by injecting or depleting carriers in the microring optical waveguide • Shifting the index of refraction will shift the microring resonant frequency and thus its transfer curve • The resulting modulation in resonant frequency will cause intensity modulation on the optical carrier

  5. Wavelength Channel Distribution FREE SPECTRAL RANGE 4 WAVELENGTH CHANNELS 100 GHz FSR (GHz) FSR = 500 GHz Radius (µm) FSR = 500 GHz corresponds to R = 24 µm

  6. Quality Factor and RC Parasitic Limits QUALITY FACTOR LIMITED BANDWIDTH RC LIMITED BANDWIDTH f3dB (GHz) f3dB (GHz) 0=1.55 µm RL=50  Quality Factor Radius (µm) RC Parasitics do not limited the bandwidth 2.5 Gb/s switching speed requires Q = 80,000 10 Gh/s switching speed requires Q = 20,000

  7. Transfer Function at Resonance POWER TRANSMISSION si st 2 = 0.063  = 0.54 cm-1 sd Carrier Density (cm-3) Target 10 dB Extinction Ratio

  8. Carrier Transport Simulation SWITCHING DYNAMICS CARRIER CONCENTRATION

  9. Previous Results on Passive Si Microdisk Resonators • Microdisk resonators have been fabricated on Si • Optical performance characterized • Optical Q > 100,000 was demonstrated

  10. Si Microring Modulator Schematic P-type Regions Input Port Drop Port Transmit Port SOI N-type Region Add Port

  11. N-type Doping P-type Doping 0.45 m 0.2 m A B 0.05 m 0.45 m BOX Cross Section TOP VIEW C D B A A-B CROSS SECTION C-D CROSS SECTION P-type Doping N-type Doping C D BOX

  12. BPM Waveguide Simulations STRAIGHT WAVEGUIDE CURVED WAVEGUIDE Oxide Oxide Si Si Oxide Oxide Width = 0.45 m Rib height = 0.2 m Slab height = 0.05 m Radius = 24 m

  13. Mask Layout RF and DC Biasing Pads Input Port Transmit Port Microring Resonator 250 microns Drop Port Add Port

  14. Fabrication Process (1) Waveguide Dry Etching (2) Hydrogen Anneal (3) P+ Implant (5) Recrystallization/Dopant Activation Anneal (4) N+ Implant (6) Ni-Silicide (7) Passivation/Via (7) Contact Pads/Interconnect

  15. Complete 0.35μm CMOS on 6” wafers 0.35μm Deep UV Lithography: ASML 5500/90 Stepper Device group demonstrated FIN FET with 60 nm gate length (King, Hu, Bokor) Berkeley Microlab Capability

  16. Si-Modulator Testbed RF Source DC Voltage Source Bias-T DUT IR Camera PC ECTL EDFA VOA /2 Plate Polarizer Free-Space Optical Bench ESA OSA RF Amp BERT PD Oscilloscope Electrical Characterization

  17. Summary • Reviewed preliminary study on an all Si based microring modulator array • Exploit SOI technology and CMOS compatible fabrication process • Built testbed for device characterization • 1st generation device target • 2.5 Gb/s • Single wavelength channel • Free spectral range ~ 0.5 THz • Next generation device • 10 Gb/s • Q = 20,000 • 4 wavelength channels (100 GHz spacing) • Low power (~µW)

More Related