Method of disposing conductive bumps onto a semiconductor device and semiconductor devices so formed

Abstract

A method of forming conductive structures on the contact pads of a substrate, such as a semiconductor die or a printed circuit board. A solder mask is secured to an active surface of the substrate. Apertures through the solder mask are aligned with contact pads on the substrate. The apertures may be preformed or formed after a layer of the material of which the solder mask is comprised has been disposed on the substrate. Conductive material is disposed in and shaped by the apertures of the solder mask to form conductive structures in communication with the contact pads exposed to the apertures. Sides of the conductive structures are exposed through the solder mask, either by removing the solder mask from the substrate or by reducing the thickness of the solder mask. The present invention also includes semiconductor devices formed during different stages of the method of the present invention.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of application Ser. No. 09 / 736,795, filed Dec. 14, 2000, now U.S. Pat. No. 6,861,345, issued Mar. 1, 2005, which is a divisional of application Ser. No. 09 / 385,584, filed Aug. 27, 1999, pending.BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] The present invention relates to methods of disposing conductive structures, such as solder bumps, onto the surfaces of semiconductor devices. In particular, the present invention relates to methods of employing solder masks made of dielectric materials to substantially simultaneously dispose a plurality of solder bumps onto a semiconductor device. More specifically, the present invention relates to conductive structure disposition methods wherein the dielectric solder mask is removable from the semiconductor device or may otherwise be altered during or subsequent to forming the conductive structures to expose the sides, or peripheries, of the c...

AI Technical Summary

Benefits of technology

"The present invention provides a method for disposing solder bumps on a substrate, such as a bare or minimally packaged semiconductor device or a printed circuit board. The method involves using a solder mask made of dielectric material with apertures that align with contact pads of the substrate. The solder mask is placed on the substrate and conductive material, such as solder or conductive elastomers, is applied through the apertures to form conductive structures on the contact pads. The solder mask can then be removed or reduced in thickness to expose the sides of the conductive structures. The invention also includes semiconductor devices with the solder mask and conductive structures formed thereon. The technical effects of the invention include improved solder bump formation and reduced cost and complexity in semiconductor device manufacturing."

Problems solved by technology

Thus, the apertures of dry film and polymeric solder masks may not define the configuration of solder bumps; rather, dry film and polymeric solder masks are typically used to position spherical solder bumps on the contact pads of a substrate.

The use of such a carrier film is, however, somewhat undesirable since, during application of the film to the printed circuit board, air pockets may form between the film and the printed circuit board and a sufficient contact between one or more of the conductive bumps and their corresponding contact pads may not be established.

Thus, the conductive bumps may not secure sufficiently to their corresponding contact pads on the printed circuit board to establish an adequate electrical connection with the contact pads.

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