Lsi Logic Corporation

Rambus Inc.

Nitin Juneja

Aritharan Thurairajaratnam

Ming Chu Li

Shahram Nikoukary

Jonghyun Cho

Ely K Tsern

David A Secker

Wendemagegnehu Beyene

Disclosed is an integrated circuit die of a memory buffer integrated circuit that is placed aggregately closer to the solder balls that connect to the input (i.e., host command/address—C/A) signals than the output solder balls (i.e., memory device C/A) signals. This decreases the length of the host C/A signals from the memory controller to the memory buffer device when the memory module is placed in a system.

Packaged integrated device with memory buffer integrated circuit die and memory devices on module substrate

Disclosed is an integrated circuit die of a memory buffer integrated circuit that is placed aggregately closer to the solder balls that connect to the input (i.e., host command/address&#x2014;C/A) signals than the output solder balls (i.e., memory device C/A) signals. This decreases the length of the host C/A signals from the memory controller to the memory buffer device when the memory module is placed in a system.

Packaged integrated device having memory buffer integrated circuit asymmetrically positioned on substrate

Disclosed is a package-on-package (PoP) assembly comprises a two-tiered windowed ball grid array (BGA) and a system on a chip (SoC) package. Window openings in the two tiers of the BGA are of different sizes to allow for wirebond landing pads on the first tier. A DRAM die is mounted to the BGA flipped over (i.e., wirebond pads facing the BGA package.) The DRAM die is wirebonded through the window in the BGA. For multi-channel systems and higher memory capacity, the DRAM die will have low-cost through-silicon vias (TSVs) that connect to stacked DRAM die(s). The stacked DRAM dies may be offset or rotated to align active TSVs with passive TSVs thereby enabling unique connections to certain DRAM dies in the stack.

Stacked die package with aligned active and passive through-silicon vias

A BGA package wherein power is provided to the die through power (Vdd) balls which are located in an inner most row of solder balls. By arranging the power balls in an inner most row, it is possible to reduce the distance the electrical signal has to travel to reach a power ring. Preferably, ground is provided to the die through ground (Vss) balls which are dispersed in a ball field around the periphery of the inner most row of power balls. Preferably, the ground balls are paired together, because by pairing the ground balls, it is possible to use only one via for two ground balls on the system board. This reduces the number of layers needed on the system board to route all of the pins and may make it possible, for example, to route more traces on the system board.

Layout of Vdd and Vss balls in a four layer PBGA

A method of making a ball grid array package includes the steps of (a) laying out an even I/O pad row and an odd I/O pad row of m I/O pads each for a ball grid array package wherein m is a positive integer, (b) laying out an even via row of m&plus;1 vias directly below each odd I/O pad row, and (c) laying out an odd via row of m&minus;1 vias directly below each even I/O pad row. A ball grid array package includes an even I/O pad row and an odd I/O pad row of m I/O pads each wherein m is a positive integer, an even via row of m&plus;1 vias directly below each odd I/O pad row, and an odd via row of m&minus;1 vias directly below each even I/O pad row.

Method for increasing trace rows of a ball grid array

A semiconductor package is disclosed. According to one embodiment, the package comprises a substrate having a top surface with traces thereon and a bottom surface with solder balls thereon, the substrate comprising at least three material layers defining at least four substantially planar metal layers, wherein one of the metal layers comprises a reference layer that serves as a reference to both traces on a metal layer above the reference layer and traces on a metal layer below the reference layer. A semiconductor die is mounted to the substrate and bonding wires electrically connect the semiconductor die to the traces on the top surface of the substrate. The traces on the top surface of the substrate are electrically connect to the solder balls through vias and possibly through routing on another metal layer.

Growing community of inventors

Fremont, CA, United States of America

Nitin Juneja