We have developed, tested and used advanced surface mounting technologies

SMT Technologies

POP assembly consists of two or more fine-pitch ball grid arrays (BGAs) stacked one atop another. In a two-piece assembly, the bottom package is usually a high-density logic device, while the top package is a high-capacity memory device. Both devices can contain more than one die. To accommodate the upper package, a thin layer of mold compound is applied to the center of the lower package, just to cover the die and wire bonds. Solder balls on the bottom of the upper package connect with I/O pads on the top of the lower package.

POP assemblies are produced using the standard surface-mount process-with an extra hitch. The BGAs are fed from tape or trays. First, solder paste for the lower BGA is deposited on the board with a stencil printer, and the BGA is placed onto the board. Next, the second BGA is picked up and-here’s the hitch-dipped into a film of specially formulated “tacky” flux or solder paste just far enough to wet the balls. The second BGA is then placed atop the first one, and the entire board is reflowed as normal, preferably in a convection oven with a nitrogen atmosphere.

Microwave boards with metal base

Metal core PCB (MCPCB) is designed to allot the heat from some extremely heating elements of electronic devices, where typical thick copper foil and cooler solutions won’t give the desired effect.

What is metal base PCB

The structure has two general elements – pcb and metal base. ELFARO can supply materials that have either aluminium or copper backing ranging in thickness from 0.4mm to 6.0 mm. Circuits can also be made from any of the available microwave laminates and post bonded to prefabricated metal structures using either electrically conductive or non-conductive sheet adhesives. Laminates can be standard FR-4 materials or special laminates like Rogers Ro4000 series. As a gluing layer we offer standard prepreg (FR-4 class) or bond ply with acrylic adhesion. The most complex model is to use adhesive layers containing silver paste which provide the best thermo- and electro-conductive connection between pcb and metal base.