PBGA electrical noise isolation of signal traces
US6825554B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 2003 |
| Grant date | Nov 30, 2004 |
| Priority date | — |
| Expiry date | Mar 11, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/3025
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for fabricating a semiconductor package having a 2-layer substrate, which includes an array of solder balls, is disclosed. The method includes patterning signal traces on a top layer of the substrate and identifying groups of signal traces to isolate. According to the present invention, a grounded isolation trace is then patterned adjacent to one of the groups of traces to isolate the signal traces, thereby providing noise shielding. In a preferred embodiment, the grounded isolation trace is provided with multiple vias, rather than only one. In a further aspect of the present invention a row of solder balls is connected together and to ground to create a bottom-layer isolating ground trace to further reduce noise. The bottom-layer isolating ground trace may be connected to the top-layer isolating ground trace using a via.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.