Browse Prior Art Database

PREDETERMINED APERTURE THICKNESS, THIN FILM PRINTING

IP.com Disclosure Number: IPCOM000009772D
Original Publication Date: 2000-May-01
Included in the Prior Art Database: 2002-Sep-18
Document File: 1 page(s) / 60K

Publishing Venue

Motorola

Related People

Tan Seak Huat: AUTHOR [+3]

Abstract

Conventional solder paste printing requires stencils. A stencil serves as an interface to provide paste imaging on a circuit substrate such as a printed circuit board (PCB). The introduction of new products has increased the number of stencils fabricated. This creates a large amount of stencil fabrication and scrap cost. A new technique is disclosed to alleviate the need to fabricate conventional stencils.

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MOTOROLA

Technical Developments

PREDETERMINED APERTURE THICKNESS, THIN FILM PRINTING

by Tan Seak Huat, Anq Bee Bee and Nyo We Kok

INTRODUCTION

Conventional solder paste printing requires stencils. A stencil serves as an interface to provide paste imaging on a circuit substrate such as a printed circuit board (PCB). The introduction of new products has increased the number of stencils fabricated.

This creates a large amount of stencil fabrication and scrap cost. A new technique is disclosed to alleviate the need to fabricate conventional stencils.

OPERATION

1. A thin film with a predetermined thickness is attached to the surface of a PCB. Apertures are formed on the thin film when the PCB is subjected to photo imaging and etching processes. Each of the apertures will match directly to the PCB's pad stack with a 1:1 ratio.

Thin Film

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2. Solder paste is then applied on PCB covered with the thin film. Precise solder paste height and coverage can be obtained through tightly sealed contact printing.

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Motorola, Inc. 2000

3. The thin film is removed through a de-ionization process. A probe specially designed with vacuum suction will de-ionize the thin film and pick it up from the PCB without smearing the solder paste.

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ADVANTAGES

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