Abstract
The design and proper selection of low-cost printed circuit board (PCB) is essential to the reliability and formation of solder joints for the fine-pitch solder-bumped flip-chip on board (FCOB) technology. By nature low-cost PCBs don't have the precision in patterns like the fine-pitch solder-bumped flip-chip technology. In this study, eutectic solder bumps (63Sn/37Pb) were electroplated on the test chips with various pad pitches and chip sizes. Several types of low-cost PCB designs were evaluated for the fine-pitch solder-bumped flip-chip. The effects of different PCB designs on the formation and shapes of solder joints were studied. The location and formation of voids in the underfill depend on the design and properties of the PCB. The alignment accuracy of the solder mask opening area and the copper pad on the PCB is very critical for the reliability of FCOB technology. The acceptable mis-registration on the low-cost PCB decreases as the chip size increases. Scanning acoustic microscope (SAM), X-ray imaging system, cross-sectioning, scanning electron microscopy (SEM) were used to evaluate and inspect the samples after the thermal cycling test and temperature-humidity test. The solder joint failure modes after thermal tests were studied.
| Original language | English |
|---|---|
| Pages (from-to) | 598-605 |
| Number of pages | 8 |
| Journal | Proceedings - Electronic Components and Technology Conference |
| Publication status | Published - 1 Jan 2001 |
| Externally published | Yes |
| Event | 51st Electronic Components and Technology Conference - Orlando, FL, United States Duration: 29 May 2001 → 1 Jun 2001 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering