CHIP-SCALE TESTING LABORATORY
The TOAN testbed facility has recently expanded its photonic devices testing facility into a dedicated lab: the CIAN Chip-Scale Testing Laboratory (CST). The CST has the capability to characterize unpackaged passive and active photonic chips and is directly connected to TOAN testbed through single-mode fiber and gigabit-Ethernet. This connectivity enables the insertion and evaluation of the unpackaged photonic chips on the network as a system. Pictures of the CST laboratory and a list of its capabilities are described below.
The CST facility supports characterization of passive waveguide devices as well as active devices such as lasers, modulators, transmitters and receivers. Optical signals can be coupled on and off chip via lensed fibers, butt coupling, or other specialized means. Passive device characterization can be performed through all fiber-optic telecommunication bands. Active characterization includes S-parameter testing up to 67GHz, and BER and eye-diagram testing up to 32Gb/s.
For system-level testing, packet streams up to 40Gb/s can be flowed through the device, and the network’s ability to process the return streams with suitable latency, bit rates, and in accordance with the modulation schemes being run, can be evaluated.
Passive Testing Capabilities and Equipment
The passive testing area includes two fixed device characterization stations [Figure 2] with high resolution microscopes. Other equipment and capabilities include:
- High sensitivity IR-beam cameras
- Precision piezo-enabled 6-axis fiber-coupling stages and 6-axis controllers
- Vacuum pick/place and holding equipment for delicate chips, and TEC enabled chip holders
- Leica DMLM Multi Measure II Metrology Microscope (resolution down to 100s of nm)
- Starrett EZ200 commercial metrology microscope (resolution of few um, and onboard image processing to automatically recognize and measure larger features on chips)
- Agilent 86038B Photonic Dispersion and Loss Analyzer
- ANDO and Agilent Optical Spectrum Analyzers, Low Noise Tunable Lasers and Optical Power Meters (all Fiber-Optic Telecommunication Bands)
- Thermal Chamber for temperature and humidity controlled measurements
Figure 2. Passive Device Testing area of the CST Laboratory
Passive Measurements
- Spectral Insertion Loss, Spectral Cross Talk and Polarization Dependent Loss (All Fiber-Optic Telecom bands) [Figure 3]
- Material/Fiber Dispersion (S,C,L bands)
- Photonic Chip Physical Features (100nm to few microns)
Figure 3. Sample Passive Measurements
Active Testing Capabilities and Equipment
The active testing area has three device characterization stations [Figure 4]. Other equipment and capabilities include:
- 40 GHz RF probes in various finger combinations with 4-axis holders
- 50GHz and 67GHz 3-finger RF probes with 4-axis holders
- Various lower speed standard and differential probes with 3-axis holders
- 3 and 6-axis fiber-coupling stages
- Fiber-Optic Modulators and Receivers up to 50GHz analog bandwidth
- Agilent N4373D Lightwave Component Analyzer (measures up to 67 GHz)
- Agilent 86100A 53-63GHz , 4 channel Infiniium DCA Oscilloscope
- Anritsu MP1800A 32Gb/s BERT system (Up to two channels of 32Gb/s measurement)
- Yokogawa NX4000 40Gb/s Transport Analyzer
Figure 4. Active Device Testing Area of the CST Laboratory
Active Measurements
- BER and Eye-Diagram testing up to 32Gb/s
- Optoelectronic S-parameter measurements up to 67GHz
- Optical Transport System analysis up to 40Gb/s
Figure 5 shows examples of the active testing measurements.
Figure 5. Sample Active Measurements
SOFTWARE CAPABILITIES
In addition to the laboratory hardware, researchers have access to a variety of software packages to enable the design and analysis of photonic integrated circuits and integrated opto-electronics including:
- VPI: component maker, transmission maker
- Lumerical: FDTD, mode solutions, device and interconnect
- Fimmwave, optiBPM
- COMSOL multiphysics package
- HFSS: including high and low frequency simulations plus signal integrity
- ZEMAX
