1.0  Introduction

The past few years have seen continued growth in the use of leadless components on ceramic circuit boards in military equipment. During this period, problems in system design and manufacturing have raised serious concerns about the inherent reliability and producibility of this packaging and interconnection technology. Solutions have been found for these problems, have been identified and are presented in this document.

1.1 OBJECTIVE AND SCOPE

This document provides best practices for the application, design, and manufacture of ceramic-based thick film multilayer interconnect boards (MIBs) and their assembly with leadless components. The scope has been limited to leadless components and ceramic substrates with either copper or noble metal (gold, platinum gold, palladium gold) thick film conductors. Excluded from consideration

• Cofired ceramic MIB technology
  
• Temperature-compensated polymer multilayer boards
  
• Surface-mounted leaded chip carriers (LDCC)
  
• Silver thick film conductors
  
• Thick film resistors
  

The leadless components themselves are not considered in detail except for those characteristics that affect assembly to the ceramic circuit board. The document addresses program management, design practices, and manufacturing practices. It is directed primarily to persons who are experienced with fabrication and use of thick film hybrid circuit and ceramic MIBs, but includes general information on the technology which will be of value to others. Many development programs in progress may throw new light on presently gray areas, but the procedures recommended here represent best practice at this time.

1.2 HOW THIS DOCUMENT WAS PREPARED

An industry-government task group was established with Navy support in April 1985 to draft these guidelines. This task group represents the major manufacturers of ceramic circuit boards and modules utilizing leadless components on ceramic circuit boards for use in Navy electronic equipment. The task group was cochaired by D. W. Cottle (Raytheon) and D. O. Patterson (RM&QA Directorate, Assistant Secretary of the Navy for Shipbuilding and Logistics). Task group secretary was E. P. Padgett (GE), and technical members included the following:

EXECUTIVE COMMITTEE

D.W. Cottle Raytheon
D.O. Patterson ASN(S&L)(RM&QA)
E.P. Padgett, Jr. GE
J.M. Gorres Sperry
R.F. Kolc RCA
A.J. McDonald McDonnell Douglas
J. Page Honeywell
A. Pfahnl AT&T Bell Laboratories
R.F. Redemske Teledyne Microelectronics
M. Schneider Hughes Aircraft

SUBCOMMITTEE ON DESIGN PRACTICES
A.J. McDonald McDonnell Douglas
S. Anderson Raytheon
S. Farran Naval Weapons Support Center
D.J. Pawlicki Sperry
R.F. Redemske Teledyne Microelectronics
J. Royston Hughes Aircraft
R. Schmidt Rockwell Autonetics
T. Webb McDonnell Douglas

SUBCOMMITTEE ON MATERIALS

R. F. Kolc RCA
J. Grier Raytheon
J. Henderson Naval Weapons Support Center
D. Lutz Honeywell
P. McDade GE
G. Mitchell Sperry
L. Sanchez McDonnell Douglas
C. Steddom Hughes Aircraft

SUBCOMMITTEE ON MIB FABRICATION

M. Schneider Hughes Aircraft
D. Bridges McDonnell Douglas
G. Hurst Tracor
C. Heslin Raytheon
G. Mitchell Naval Weapons Support Center
D. Palacheck Sperry
D. Pitkanen Honeywell
R. St. Pierre Boeing
J. Thompson General Dynamics

SUBCOMMITTEE ON MODULE ASSEMBLY

A. Pfahnl AT&T Bell Laboratories
S. Fenger Hughes Aircraft
L. Goldberg Ford Aerospace
R. Kraus Control Data
S. Livingston Litton Amecom
D. McMahon Sperry
B. Mulligan General Dynamics
L. Nash Naval Weapons Support Center
J. Prokop Texas Instruments
J. St. Jean Raytheon

SUBCOMMITTEE ON RELIABILITY ASSESSMENT

D.W. Cottle Raytheon
W. Beach McDonnell Douglas
J.P. Bradley Hughes Aircraft
A. Burnett Naval Wapons Support Center
K.B. Dalager Sperry
E. D. Pisacich Honeywell
S. Rapp Naval Weapons Support Center
P. Scher RCA
T. Schilsky RCA

RELIABILITY DATA CONTRIBUTORS

The following organizations contributed data to provide the basis for the reliability assessment:

Johns Hopkins University (Applied Physics Laboratory)
AT&T Bell Laboratories
Ford Aerospace
Honeywell
Hughes Aircraft
IBM
McDonnell Douglas
Naval Weapons Support Center
Raytheon
RCA
Reliability Analysis Center, RADC
Sperry
Texas Instruments