Package substrate having embedded capacitor

Abstract

A package substrate having embedded capacitor is provided. The package substrate includes a first core circuit board, at least one embedded capacitor, a second core circuit board and a dielectric layer. At least one metal layer is disposed on a surface of the first core circuit board and at least one first conductive through hole of the first core circuit board is connected to the metal layer. The embedded capacitor is embedded in the first core circuit board and connected to the metal layer. A wiring layer is disposed on a surface of the second core circuit board and at least one second conductive through hole of the second core circuit board is connected to the wiring layer. The dielectric layer is laminated between the first and the second core circuit boards.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the priority benefit of Taiwan application serial no. 95141129, filed Nov. 7, 2006. All disclosure of the Taiwan application is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a package substrate, and more particularly to a package substrate having embedded capacitor.[0004]2. Description of Related Art[0005]Embedded capacitor can be integrated into a package substrate in the same fabrication process to enhance the efficiency of the active components inside an electronic package, improve electrical performance and lower assembling cost. Therefore, it has become the mainstream method for fabricating electronic carrier. At present, the development of embedded capacitor is mainly aiming toward small size ceramic capacitors. In general, ceramic capacitors can be classified into single layer ceramic capacitors (SLCC) and multi-layer ceramic ...

AI Technical Summary

Benefits of technology

[0008]Accordingly, the present invention directs to a package substrate having embedded capacitor for enhancing the space and degree of freedom of disposing the embedded capacitor.

[0009]The present invention also directs to a package substrate having embedded capacitor such that the performance of the package substrate is enhanced by using a dielectric material with high dielectric constant and low dielectric loss.

[0010]The present invention directs to a package substrate having embedded capacitor such that the embedded capacitor is protected from damage by covering it with a passivation layer.

[0018]Due to the improvement in the substrate structure, the embedded capacitor in the present invention can be disposed in a suitable location without having to avert the conductive through hole. Therefore, the space and degree of freedom for disposing the embedded capacitors is enhanced. In addition, capacitors fabricated using high dielectric constant and low dielectric loss material such as polymer-ceramic composite can be used instead of the conventional discrete capacitors so as to enhance the performance of the package substrate. Furthermore, the embedded capacitors of the present invention is covered with at least one passivation layer to prevent the embedded capacitors from receiving possible damage in the process of compressing the substrate. Hence, overall reliability of the package substrate is improved.

Problems solved by technology

However, because the capacitance of the conventional discrete capacitor is low and has a low dielectric constant, they could hardly enhance the performance of a conventional circuit substrate.

In the meantime, the discrete capacitors 130 are easily damaged or broken in the process of compressing the substrate.

Images