Unlock instant, AI-driven research and patent intelligence for your innovation.

Wire bonding capillary tool having multiple outer steps

a capillary tool and wire bonding technology, which is applied in the direction of manufacturing tools, soldering devices, auxillary welding devices, etc., can solve the problems of cratering, low thermal conductivity, and poor mechanical properties of materials with such sensitive metallization, and failure of the device or equipment in which the faulty connection is mad

Inactive Publication Date: 2009-12-17
SMALL PRECISION TOOLS
View PDF1 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0014]In one aspect, the present invention provides a bonding tool for bonding a fine wire to a substrate. The bonding tool comprises an at least substantially cylindrical portion having a concentric capillary therein through which the fine wire runs; and a working tip portion formed at an end of the cylindrical portion being tapered towards the tip thereof, said working

Problems solved by technology

An improper or faulty electrical connection between the electrical component and the PCB is likely to result in the functional failure of the device or equipment in which the faulty connection occurs.
The most common reason for insufficient inter-diffusion is the presence of foreign materials or contaminants on the surface of the bond pad, such as oxides, unetched glass, silicon saw dust, and process residues, for example.
Generally, materials with such sensitive metallization have poor mechanical properties, low thermal conductivity and are more susceptible to metal peel-off, cratering and oxide cracks during wire bonding.
Bonding tools, where the amount of combined mechanical stress from the applied ultrasonic energy, impedance and the impact force of said bonding tool on the bond pad may result in serious damage occurring to the bond pads with sensitive metallization.
Furthermore, such conventional bonding tools may not be able to form bonds reliable enough for carrying out ‘bonding over active circuitry’.
Typically, when a conventional bonding tool, such as that described in the aforesaid U.S. Pat. No. 6,910,612, is used in conjunction with a substrate of a low K value, the ultrasonic energy delivered at the working tip of conventional bonding tools is usually insufficient to bond low K bond pads through metallization.
However, if a higher ultrasonic energy is supplied, it tends to further aggravate the above-mentioned problems of metal peel-off, cratering and oxide cracks.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Wire bonding capillary tool having multiple outer steps
  • Wire bonding capillary tool having multiple outer steps
  • Wire bonding capillary tool having multiple outer steps

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

[0037]Accordingly, in the first embodiment, a diametric decrease takes place at a distance of about 7.10 mm and about 2.65 mm. Since the diametric decreases takes place consecutively in the direction of the working tip, the diameter prior to the first discrete interval, D1 (about 1.587 mm), is greater than the diameter, D2 (about 1.20 mm) thereafter. Accordingly, it follows that the diameter, D2, prior to the second discrete interval is about 1.20 mm and the diameter, D3, thereafter is about 0.82 mm. Therefore, in this embodiment, the diameter decreases in fixed amounts at each discrete interval. That is, at the first discrete interval, the diameter decreases from about 1.587 mm to about 1.20 mm and subsequently, at the second discrete interval, from about 1.20 mm to about 0.82 mm. Two discrete intervals create three distinct diameters over the length of the bonding tool of the first exemplary embodiment.

[0038]In a second exemplary embodiment where the bonding tool has three discret...

second embodiment

[0054]FIG. 3 shows the bonding tool 300 according to the present invention having three discrete intervals 303, 306, 309 along the entire length of the capillary 302. The diameter of the bonding tool 300 is initially 1.587 mm at 301. After the first discrete interval at 303, the diameter of the bonding tool 300 decreases to 1.331 mm at 304. Subsequently, after the second discrete interval at 306, the diameter of the bonding tool 300 decreases to 1.076 mm at 305. Finally, after the third discrete interval 309, the diameter decreases again to 0.82 mm at 307.

[0055]FIG. 4 shows a third embodiment 400 of the bonding tool according to the present invention. The bonding tool 400 has four discrete intervals 403, 406, 408 and 409 along the entire length of the capillary 402. The diameter of the bonding tool 400 is initially at about 1.587 mm at 401. After the first discrete interval at 403, the diameter of the bonding tool 400 decreases to about 1.395 mm at 404. Subsequently, after the secon...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Angleaaaaaaaaaa
Angleaaaaaaaaaa
Diameteraaaaaaaaaa
Login to View More

Abstract

A bonding tool for bonding a fine wire to a substrate, said bonding tool comprising an at least substantially cylindrical portion having a concentric capillary therein through which the fine wire runs; a working tip portion formed at an end of the cylindrical portion being tapered towards the tip thereof, said working tip portion having an annular chamfer at the tip thereof; wherein the concentric capillary opens into the annular chamfer of the working tip, and wherein the diameter of the cylindrical portion decreases consecutively at a plurality of discrete intervals along the length of the cylindrical portion towards the working tip portion.

Description

STATEMENT OF RELATED APPLICATION(S)[0001]This is a continuation of U.S. patent application Ser. No. 11 / 400,927 filed on Apr. 10, 2006. The disclosure of the foregoing application is hereby incorporated by reference herein in its entirety, for all purposes, and the priority such application is hereby claimed under the provisions of 35 U.S.C. § 120.FIELD OF THE INVENTION[0002]The present invention relates to the field of wire bonding capillary tools for bonding a fine wire to a substrate, and more specifically, to a wire bonding capillary tool having a high impedance values and being optimized for ultrasonic energy transfer compliancy.DESCRIPTION OF THE RELATED ART[0003]Printed circuit boards (PCB) are commonly used in the manufacture of digital devices, automated testing equipment (ATE) and in a range of general electronic equipment. Each PCB has a variety of electronic components mounted thereon. Examples of such components include semiconductor chips, integrated circuits (IC), resi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B23K20/10B23K37/00
CPCB23K20/004B23K2201/32H01L24/45H01L24/78H01L24/85H01L2224/05624H01L2224/45015H01L2224/45124H01L2224/45144H01L2224/45147H01L2224/48463H01L2224/48624H01L2224/48724H01L2224/48824H01L2224/78302H01L2224/85205H01L2924/01013H01L2924/01014H01L2924/01027H01L2924/01028H01L2924/01029H01L2924/01042H01L2924/01058H01L2924/01074H01L2924/01079H01L2924/01082H01L2924/01327H01L2924/04941H01L2924/14H01L2924/19041H01L2924/19043H01L2924/20751H01L2924/20752H01L2924/20753H01L2924/20754H01L2924/20755H01L2924/20756H01L2924/20757H01L2924/20758H01L2924/20759H01L2924/3011H01L2924/01006H01L2924/01019H01L2924/01033H01L2224/48451H01L2924/00014H01L2924/00B23K2101/32H01L24/48H01L2924/00015
Inventor CASTANEDA, JAIMEGOH, KAY SOON
Owner SMALL PRECISION TOOLS