US 5,635,767 A · Semiconductor device having built-in high frequency bypass capacitor

Abstract

A high frequency bypass capacitor (36, 36') is built into a thin-film portion (16, 16') of a polymer carrier substrate (15) of a PBGA (10). The carrier substrate (15) has both a stiffener (18) and a thin-film portion (16, 16') which has multiple metal layers (24, 28, 30, 32). The power supply planes (28, 30) of these metal layers are used to form built-in bypass capacitors (36, 36'), wherein the power supply planes are specifically designed to be adjacent and parallel layers. An ultra thin film laminate construction provides thin dielectric films (26) between the metal layers to allow the bypass capacitor to be placed very dose to the attached semiconductor die (12) to further reduce parasitic inductance and resistance between die connections (14) and the bypass capacitor. The built-in feature minimizes inherent parasitic series inductance and resistance, thus enabling the filtering of unwanted low pulse width glitches on a power plane connected to VLSI devices at operating frequencies at or above 100 MHz.

Claims14

Dependent claims

A semiconductor device comprising:

a thin-film substrate having a plurality of substantially parallel conductive layers, wherein every two adjacent conductive layers of the plurality of conductive layers are separated by an insulative layer and wherein the plurality of conductive layers comprises:
a signal layer;
a ground layer;
and
a power layer, wherein the ground layer and the power layer are adjacent conductive layers to form a capacitor region within the thin-film substrate to reduce noise in the semiconductor device;
a semiconductor die which is flip-chip mounted to the thin-film substrate;
a stiffening substrate that is thicker than the thin-film substrate, the stiffening substrate having a surface that is in intimate contact with and physically bonded to the thin-film substrate, the stiffening substrate having a plurality of conductive vias to maintain electrical contact with the semiconductor die that is mounted to the thin-film substrate;
and
a plurality of external electrical connections for the semiconductor device, the plurality of external electrical connections being electrically connected through the plurality of conductive vias in the stiffening substrate.

6 more elements

Dependencies are inferred from the claim text.

Semiconductor device having built-in high frequency bypass capacitor

Life of this patent

Semiconductor device having built-in high frequency bypass capacitor

Life of this patent

Abstract

Claims14