TR NWT 000930 : ISSUE 2

1 INTRODUCTION
1.1 Purpose
1.2 Definition
1.3 Scope
1.4 Approach
1.5 Application
1.5.1 Optoelectronic Modules
1.5.2 Document List
1.6 Changes from Previous Issue
1.6.1 CFC Elimination
1.6.2 Component Reliability Assurance Practices
1.6.3 New Bellcore Documents
1.7 Changes Foreseen in Future Issues
1.7.1 Multichip Modules
1.7.2 More Severe Operating Environments
1.8 Quality Levels
1.9 Requirements Terminology
2 GENERAL REQUIREMENTS
2.1 Safety
2.2 Reliability
2.3 Other Requirements
2.4 Non-Conformance
2.5 Administration
2.6 Numerical Values
2.7 Workmanship Standards
3 MATERIALS AND FINISH REQUIREMENTS
3.1 Substrates
3.1.1 Composition
3.1.2 Physical Characterization and Qualification
3.1.3 Lot-to-Lot Controls
3.1.4 Visual Imperfections
3.1.5 Dimensional Criteria
3.1.6 Camber
3.1.7 Surface Finish
3.1.8 Thermal Shock Resistance
3.1.9 Process Functionality
3.2 Thick Film Materials
3.2.1 Lot-to-Lot Controls
3.2.2 Total Solids
3.2.3 Viscosity
3.2.4 Printability
3.3 Thin Film Materials
3.3.1 Lot-to-Lot Controls
3.3.2 Material Analysis
3.4 Finishes and Coatings
3.4.1 Tin
3.4.2 Zinc and Cadmium
3.4.3 Silver
3.4.4 Plating on Brass
3.4.5 Plating on Steel
3.4.6 Plating on Solder
3.4.7 Silicones
3.5 Adhesives
3.5.1 Insulation Resistance
3.5.2 Reversion
3.6 Fluxes
3.6.1 Compliant
3.6.2 Non-compliant
4 FILM CIRCUIT REQUIREMENTS
4.1 General
4.1.1 Definitions
4.1.2 Applicability
4.1.3 Compatibility
4.1.4 Adhesion
4.1.5 Environmental Test Conditions
4.1.6 Test Patterns
4.2 Conductors
4.2.1 Qualification of Conductors
4.2.2 Lot-to-Lot Controls for Conductors
4.2.3 Visual Inspection
4.2.4 Solderability
4.2.5 Solder Leaching
4.2.6 Adhesion
4.2.7 Bondability
4.2.8 Sheet Resistance
4.2.9 Electromigration Resistance
4.3 Resistors
4.3.1 General
4.3.2 Qualification of Film Resistors
4.3.3 Lot-to-Lot Controls for Film Resistors
4.3.4 Visual Inspection
4.3.5 Trimming
4.3.6 Resistance Change
4.3.7 Temperature Coefficient of Resistance
4.3.8 Biased Humidity
4.3.9 Power Cycling
4.3.10 Voltage Coefficient of Resistance
4.4 Film Capacitors
4.4.1 General
4.4.2 Qualification of Film Capacitors
4.4.3 Lot-to-Lot Controls for Film Capacitors
4.4.4 Visual Inspection
4.4.5 Capacitance Change
4.4.6 Temperature Coefficient of Capacitance
4.4.7 Biased Humidity
4.4.8 Capacitor Leakage
4.5 Dielectric Crossovers
4.5.1 Design of Dielectric Crossovers
4.5.2 Qualification of Dielectric Crossovers
4.5.3 Lot-to-Lot Controls for Dielectric Crossovers
4.5.4 Visual Inspection
4.5.5 Dielectric Strength
4.5.6 Insulation Resistance
4.5.7 Biased Temperature and Humidity
4.6 Encapsulants and Overglazes
4.6.1 Visual Inspection
4.6.2 Functional
5 ATTACHED COMPONENTS
5.1 General
5.2 Qualification
5.2.1 Applicability
5.2.2 Packaged Components
5.2.3 Bare Semiconductor Die
5.2.4 Qualification by Similarity
5.2.5 Qualification Based on Usage History
5.2.6 Vendor-Supplied Data
5.2.7 Approved Parts List
5.2.8 Requalification
5.3 Lot-to-Lot Controls
5.3.1 Applicability
5.3.2 Packaged Components
5.3.3 Bare Semiconductor Die
5.3.4 Alternatives to Incoming Inspection
5.3.5 Vendor-Supplied Data
5.3.6 Quality Audits
5.3.7 Screening and Reliability Audits
6 ASSEMBLY REQUIREMENTS
6.1 Film Circuit Condition
6.1.1 Visual
6.1.2 Solderability
6.1.3 Bondability
6.1.4 Cleanliness of Film Circuits
6.2 Bare Die Attachment
6.2.1 Metallic Die Attach
6.2.2 Adhesive Die Attach
6.2.3 Wire Bonds
6.2.4 Beam Leads and Tape Carrier Bonding
6.3 Component Attachment
6.3.1 General
6.3.2 Component Forms
6.3.3 Solders
6.3.4 Reflow Process
6.3.5 Solder Joints
6.3.6 Mounting Pads
6.3.7 Shared Pads
6.3.8 Component Mis-Registration
6.4 Lead Frames
6.4.1 Misregistration
6.4.2 Terminal Tensile Strength
6.4.3 Terminal Fatigue Strength
6.5 Connectors
6.5.1 Performance
6.5.2 Mounting
6.6 Hermetic Packaging
6.6.1 Materials and Finishes
6.6.2 Glass Seal Integrity
6.6.3 Wire Bonds to Hermetic Packages
6.6.4 Hybrid Attachment
6.6.5 Terminal Strength
6.6.6 Marking
6.7 Conformal Coating
6.7.1 Compatibility
6.7.2 Flammability
6.7.3 Silicones
6.7.4 Insulation Resistance
6.7.5 Reversion
6.8 Protective Covers
6.8.1 Marking
6.8.2 Flammability
6.9 Cleanliness of Finished Hybrid Microcircuits
6.9.1 Solvent Extract Conductivity
7 FINISHED HYBRID REQUIREMENTS
7.1 Qualification
7.1.1 Qualification Tests
7.2 Lot-to-Lot Quality and Reliability Controls
7.2.1 Source Inspection/Incoming Inspection
7.3 Feedback and Corrective Action Program
7.3.1 Program Outline
7.4 Continuous Reliability Improvement Program
8 PRODUCT IDENTIFICATION and MARKING REQUIREMENTS
9 PACKING REQUIREMENTS
10 SPECIAL TESTS
10.1 Fire Resistance
10.2 Temperature-Humidity-Bias Testing
10.3 Silicone Extraction
10.4 Flux Corrosivity
10.5 Solvent Extract Conductivity
10.6 Electromigration Resistance
10.7 Wire Pull Adhesion
10.7.1 Summary of Test Procedure
11 REFERENCED DOCUMENTS
11.1 Referenced Bellcore Documents
11.2 Referenced Military Documents
11.3 Related IEC Documents
11.4 Referenced IPC Standards
11.5 Other Documents
12 GLOSSARY
12.1 Symbols, Acronyms and Units
12.2 Terms

Provides Bellcore's view of a minimum set of common practices and tests necessary to help to ensure the quality and reliability of hybrid microcircuits. The document includes requirements for materials, film circuitry, applied components and qualification procedures for finished hybrids.