Method for preparing low cost substrates

Abstract

A mask is formed over a first conductive portion of a conductive layer to expose a second conductive portion of the conductive layer. An electrolytic process is performed to remove conductive material from a first region and a second region of the second conductive portion. The second region is aligned with the mask relative to an electric field applied by the electrolytic process. The second region separates the first region of the second conductive portion from the first conductive portion. The electrolytic process is concentrated relative to the second region such that removal occurs at a relatively higher rate in the second region than in the first region.

Description

Background technique [0001] The present invention relates to the packaging of microelectronic devices, and more particularly to the packaging of semiconductor devices. [0002] Microelectronic devices typically include a thin sheet of semiconductor material, such as silicon or gallium arsenide, which is often referred to as a die or semiconductor chip. Semiconductor chips are typically provided as individual pre-packaged units. In some cell designs, the semiconductor chip is mounted to a substrate or chip carrier, which in turn is mounted to a circuit panel, such as a printed circuit board. [0003] Active circuitry is fabricated in a first side (eg front side) of the semiconductor chip. To facilitate electrical connection to active circuitry, the chip is provided with bond pads on the same side. The bond pads are typically arranged in a regular array, either around the edges of the die or, for many memory devices, in the center of the die. Bond pads are typically made of ...

AI Technical Summary

Problems solved by technology

Complex portable devices require packing many chips into a small space

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