Design for flip chip joint pad/LGA pad
US5811883A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1996 |
| Grant date | Sep 22, 1998 |
| Priority date | — |
| Expiry date | Sep 30, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K2201/09936
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A substrate for an integrated circuit package is provided. The substrate includes a first dielectric layer with a first coefficient of thermal expansion. The first dielectric layer has a bottom surface and an inner side surface. The inner side surface defines a first aperture. The substrate also includes a conductive pad having a bottom surface and a side surface. The side surface of the conductive pad engages the inner side surface of the first dielectric layer. The substrate further includes a second dielectric layer having a second coefficient of thermal expansion closely matching the first coefficient of thermal expansion. The second dielectric layer is deposited upon the bottom surface of the first dielectric layer and upon a first portion of the bottom surface of the conductive pad. The first portion of the bottom surface of the conductive pad is adjacent to the side surface of the conductive pad.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.