TA NWT 000983 : ISSUE 2

1 Introduction
1.1 Scope and Purpose
1.2 Failure Rate 'Goals'
1.3 Changes in the Document
1.3.1 Changes From Issue 1
1.3.2 Future Additions
1.4 Related Bellcore Documents
1.5 Terminology
1.5.1 Requirements Terminology
1.5.2 Device Terminology
1.5.3 Operating Environments
1.5.4 Other Terminology
1.6 Document Organization
2 Reliability Assurance - Overview and Philosophy
2.1 Overview of Reliability Assurance
2.2 Generic Requirements Philosophy
3 Common Requirements
3.1 Vendor and Device Qualification
3.1.1 Specification and Control
3.1.2 Vendor Approval
3.1.3 Common Criteria for Device Qualification
3.1.4 General Information for Qualification
3.1.5 Requalification
3.2 Lot-to-Lot Quality and Reliability Controls
3.2.1 Common Criteria for Lot Controls
3.2.2 General Information for Lot-to-Lot Controls
3.3 Standardized Test Procedures
3.4 Feedback and Corrective Action
3.5 Device Storage and Handling
3.5.1 Nonconforming Material
3.5.2 Material Review System
3.5.3 Stockroom Inventory Practices
3.5.4 ESD Precautions
3.6 Documentation and Test Data
3.6.1 Availability of Documentation
3.6.2 Availability of Other Information
3.7 Availability of Devices
4 Laser Reliability and Quality Criteria
4.1 Laser Diode Qualification
4.1.1 Characterization
4.1.2 Reliability Tests
4.2 Laser Diode Lot-To-Lot Controls
4.2.1 Visual Inspection
4.2.2 Optical and Electrical Testing
4.2.3 Screening
4.3 Laser Module Qualification
4.3.1 Characterization
4.3.2 Reliability Tests
4.4 Laser Modules Lot-To-Lot Controls
4.4.1 Visual Inspection
4.4.2 Optical and Electrical Testing
4.4.3 Screening
4.5 Integrated Laser Module Qualification
4.6 Integrated Laser Module Lot-To-Lot Controls
4.7 Qualification of Other Component Parts
4.8 Lot-To-Lot Controls of Other Component Parts
5 Special Procedures and Test Methods for Lasers
5.1 Wavelength & Spectral Width
5.2 Far-Field Pattern
5.3 Threshold Current
5.4 Threshold Current Temperature Sensitivity
5.5 Linearity of the L-I Curve
5.5.1 Overall Linearity
5.5.2 Saturation of Optical Output
5.5.3 Kinks
5.6 Voltage-Current Curve
5.7 Modulation Depth
5.8 Rise and Fall Times
5.9 Turn-On Delay
5.10 Cutoff Frequency
5.11 Self-Pulsation
5.12 Monitor Operation
5.12.1 Dark Current
5.12.2 Photocurrent
5.13 Thermoelectric Cooler and Temperature Sensor
              Checks
5.14 Coupling Efficiency
5.15 Front-To-Rear Tracking Ratio
5.15.1 Laser Diode
5.15.2 Laser Module
5.16 Front-To-Rear Tracking Error
5.17 Thermal Impedance
5.17.1 Threshold Current Method
5.17.2 Rollover L-I Method
5.17.3 Forward Voltage Method
5.18 Accelerated Aging
5.18.1 Analysis Methods
5.18.2 Activation Energy
5.19 Reliability Calculations
5.19.1 Median Life
5.19.2 Wear-Out Failure Rate
5.19.3 Random Failure Rate
5.19.4 Reporting of Results
5.20 Temperature Cycling
5.21 Damp Heat (Steady State)
5.22 ESD Threshold
5.23 Cyclic Moisture Resistance
6 LED Reliability and Quality Requirements
6.1 LED Qualification
6.1.1 Characterization
6.1.2 Reliability Tests
6.2 LED Lot-To-Lot Controls
6.2.1 Visual Inspection
6.2.2 Optical and Electrical Testing
6.2.3 Screening
6.3 LED Module Qualification
6.3.1 Characterization
6.3.2 Reliability Tests
6.4 LED Module Lot-To-Lot Controls
6.4.1 Visual Inspection
6.4.2 Optical and Electrical Testing
6.4.3 Screening
6.5 Integrated LED Module Qualification
6.6 Integrated LED Module Lot-To-Lot Controls
6.7 Qualification of Other Component Parts
6.8 Lot-To-Lot Controls of Other Component Parts
7 Special Procedures and Test Methods for LEDS
7.1 Wavelength & Spectral Width
7.2 LED Light-Current Curve
7.3 Modulation Depth
7.4 Rise and Fall Times
7.5 Turn-On Delay
7.6 Cutoff Frequency
7.7 Thermoelectric Cooler and Temperature Sensor Checks
7.8 Accelerated Aging
7.8.1 Analysis Method
7.8.2 Activation Energy
7.9 Temperature Cycling
7.10 Damp Heat (Steady State)
7.11 Cyclic Moisture Resistance
7.12 Endurance Tests for Other Components
7.13 Reliability Calculations
7.14 ESD Threshold
8 Photodetectors Reliability and Quality
              Requirements
8.1 Photodiode Qualification
8.1.1 Characterization
8.1.2 Reliability Tests
8.2 Photodiode Lot-To-Lot Controls
8.2.1 Visual Inspection
8.2.2 Optical and Electrical Testing
8.2.3 Screening
8.3 Detector Module Qualification
8.3.1 Characterization
8.3.2 Reliability Tests
8.4 Detector Module Lot-To-Lot Controls
8.4.1 Visual Inspection
8.4.2 Optical and Electrical Testing
8.4.3 Screening
8.5 Integrated Detector Module Qualification
8.6 Integrated Detector Module Lot-To-Lot Controls
8.7 Qualification of Other Component Parts
8.8 Lot-To-Lot Controls of Other Component Parts
9 Special Procedures and Test Methods for
              Photodetectors
9.1 Responsivity of Photodetectors
9.2 Photodetector Quantum Efficiency
9.3 Photodetector Linearity and Gain
9.4 Dark Current
9.5 Capacitance
9.6 Breakdown Voltage
9.7 Excess Noise Factor
9.8 Cutoff Frequency
9.9 Thermoelectric Cooler and Temperature Sensor
              Checks
9.10 Thermal Impedance
9.11 Accelerated Aging Life Test (Photodiodes and
              Detector Modules)
9.11.1 Analysis Method
9.11.2 Activation Energy
9.12 Temperature Cycling
9.13 Damp Heat (Steady State)
9.14 Cyclic Moisture Resistance
9.15 Endurance Tests for Other Components
9.16 Reliability Calculations
9.17 ESD Threshold
10 References
11 Glossary
11.1 Symbols, Acronyms and Units
11.2 Terms
Appendix A - Lot Tolerance Percent Defective (LTPD) Table
Appendix B - Alignment with TR-NWT-000468
LIST OF FIGURES
Figure 1-1 Examples of Optoelectronic Device Module Designs
Figure 1-2 Schematic of a Common Laser Module Design
Figure 2-1 Elements of a Comprehensive Reliability Assurance
              Program
Figure 5-1 Example of a Single-Mode Laser Optical Spectrum
Figure 5-2 Laser Far Field Pattern Measurement
Figure 5-3 Example of L-I and dL/dI Curves With a Kink
Figure 5-4 Measurement of Rise and Fall Times
Figure 5-5 Measurement of Turn-On Delay
Figure 5-6 Example of a Lognormal Probability Plot
Figure 5-7 Goldthwaite Curves
Figure 5-8 Nomograph for Calculating Random Failure Rates
Figurd 9-1 Example of Photodetector Linearity
Figure 9-2 Example of an APD Gain Profile

Presents Bellcore's preliminary view of proposed generic reliability assurance practices for optoelectronic devices used in loop applications, including laser diodes (LD's), light emitting diodes (LED's), and photodiodes (PD's). Such devices are critical to the reliability and performance of fiber-in-the-loop (FITL) systems and other major network elements (NEs).