PCB surface finishes like Immersion silver (ImAg) are commonly used in Pb-free manufacturing environments following RoHS legislation. With this transition, however the numbers of field failures associated with electrochemical migration, copper sulphide corrosion, via barrel galvanic corrosion are on a steady rise. More often than not ImAg surfaces seem to assist these failing signatures. As computers penetrate into emerging markets with humid and industrialized environments there is a greater concern on the reliability and functionality of these electronic components.

Series capacitors, under certain conditions, within high speed differential pair signals were found to have negative effects on mother board functions inside a personal computer (PC). It was noted in one case study that three conditions affected capacitors with this type of application: capacitor aging, DC offset voltage, and cold temperatures. These conditions led to the decrease in capacitance which then disabled the network connection inside the PC. It was concluded that a strategically chosen capacitor type alleviates these conditions. The capacitor type primarily depends on the dielectric material.

Comprehensive in situ (designed-in) diagnostic capabilities have been incorporated into digital microelectronic systems for years, yet similar capabilities are not commonly incorporated into the design of analog microelectronics. And as feature sizes shrink and back end interconnect metallization becomes more complex, the need for effective diagnostics for analog circuits becomes ever more critical. This paper presents concepts for incorporating in situ diagnostic capability into analog circuit designs. Aspects of analog diagnostic system architecture are discussed as well as nodal measurement scenarios for common signal types. As microelectronic feature sizes continue to shrink, diagnostic capabilities such as those presented here will become essential to the process of fault localization in analog circuits.

The existing failure analysis (FA) tool used in the manufacturing was unable to support multiple input multiple output (MIMO) analysis and it has poor user interface capability. The tool used by hardware engineers and design engineers is capable for all radio frequency (RF) analysis including MIMO, but yet it is an extremely expensive tool with rigid interface due to the need for automation. Wireless advanced FA tool (WAFT) was then designed, developed, and deployed as a single solution to FA engineers to perform all the RF analysis including MIMO in a user friendly interface and affordable setup. This article provides information on design planning, application, validation, and deployment of WAFT as well as on transmit quality and receive quality evaluation. WAFT has been validated in providing accurate measurement by benchmarking with the existing tools. WAFT provides the interactive controllability and comprehensive signal analysis capability including MIMO needed for FA.