Storage Reliability of Chip and Bond Wire Electronic Devices. Volume 1. Data Analysis
Abstract
Storage reliability and parameter drift rates were measured on 10,027 Minuteman chip and bond wire Resistor-Transistor Logic (RTL) devices, which have been in storage since mid-1967 (eight years). Three parts failed as a result of the eight years of storage. Analysis of the failed parts showed all three were caused by oxide defects which allowed the deposited aluminum metalization to contact the active silicon of the die and short to ground. The 90% confidence level values for Failure Rate and Mean Time Between Failure are 9.5 x 10 to the -9th power failures/part-hr and 105 million part-hrs/failure, respectively. After eight years of storage, none of the parts experienced a single bond wire failure, no external leads were corroded or broken and there were no package problems. This is evidence of the high storage reliability that can be achieved with proper design, manufacturing and test procedures. Parameter drift measurements showed the resistor elements virtually unchanged after 8 years of storage. However, the transistor elements showed a significant degradation in gain characteristics. The gain changes are attributed to migration of contaminants (which are always present in minute amounts), and/or to changes in the gold doping process used in the manufacture of the parts. The strong correlation between original measured performance and drift rate suggests that storage life can be enhanced significantly by rejecting parts that fall below the -1 sigma level during acceptance testing.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 08, 1975
- Accession Number
- ADA077485
Entities
Organizations
- Boeing