Browse Prior Art Database

Structure and Method of Manufacturing Fine Pitch Pre-Placed Vias

IP.com Disclosure Number: IPCOM000238078D
Publication Date: 2014-Jul-31
Document File: 5 page(s) / 193K

Publishing Venue

The IP.com Prior Art Database

Abstract

This document describes a method of manufacturing fine pitch vias that can later be placed into a microelectronics package to form a series of electrical connections through the body of a microelectronics package. These fine pitch via arrays can replace existing processing technologies for Through Package Vias (TPV’s) which require a drilling process through the package, followed by filling the dilled via with a conductive paste that is subsequently cured. Existing pre-placed vias typically utilize a single conductive pillar. Though effective in forming an electronic connection through the body of the microelectronics package, the TPV or pre-placed conductive pillar, will generally require a minimum 300um diameter area. The method described within this document will enable arrays of fine pitch vias (<25um diameter) to be placed in the same foot print of a single TPV or pre-placed conductor, thereby creating a multitude of through package interconnects without significant usage of available package space. These fine pitch via arrays can be used in the manufacture of Fan-out Wafer Level Packages (FOWLP), Multi-chip Modules (MCM) or similar microelectronics packages that require a large number of through package interconnects.

This text was extracted from a Microsoft Word document.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 52% of the total text.

Structure and Method of Manufacturing Fine Pitch Pre-Placed Vias

ABSTRACT

            This document describes a method of manufacturing fine pitch vias that can later be placed into a microelectronics package to form a series of electrical connections through the body of a microelectronics package. These fine pitch via arrays can replace existing processing technologies for Through Package Vias (TPV’s) which require a drilling process through the package, followed by filling the dilled via with a conductive paste that is subsequently cured. Existing pre-placed vias typically utilize a single conductive pillar. Though effective in forming an electronic connection through the body of the microelectronics package, the TPV or pre-placed conductive pillar, will generally require a minimum 300um diameter area. The method described within this document will enable arrays of fine pitch vias (<25um diameter) to be placed in the same foot print of a single TPV or pre-placed conductor, thereby creating a multitude of through package interconnects without significant usage of available package space. These fine pitch via arrays can be used in the manufacture of Fan-out Wafer Level Packages (FOWLP), Multi-chip Modules (MCM) or similar microelectronics packages that require a large number of through package interconnects.

METHOD

            This manufacturing method begins in a manner very similar to the manufacture of a microelectronics package such as a quad flat no lead package (QFN) or MAPBGA  wherein a Wire Bond Diagram and Package Outline drawings are created. The wire bond diagram defines a substrate, wire type, wire bond locations, and wire loop heights. The package outline drawing defines the final package dimensions – length, width and height.    In forming the fine pitch via arrays, the substrate is sacrificial and can be a lead frame, a FR4 substrate or any material simply able to support a wire-bondable metal film and withstand the typical wire bond parameters for example, heat and force. Referring to Figure 1, wire bonds are formed on the sacrificial substrate as defined by the bond diagram and may have the same loop height to form parallel arrays or of alternating loop heights to form staggered arrays.

 

            Figure 1: Wire arrays bonded to sacrificial substrate

Once the wire bonds are formed, the substrate and wires are overm...