SIPLACE 80 F4_EN.pdf - 第29页

28 Description The Flip Ch ip component vision module extend s the c apability of processing Fine Pitch and Fl ip Chip components with extreme fine lead pitches. T his add-on modu le for the Fine Pitch component v i- sio…

Description

The Fine Pitch component vision

module operates according to a

sophisticated lighting technology

and utilizes diverse analysis algo-

rithms. Despite the great diversity

of components it boasts a very

high recognition reliability with all

SMD modules. Like all other vision

modules, this one is also con-

nected to the station’s vision

processor.

The components are illuminated

from three lighting planes whose

intensity can be adjusted in 256

increments. This enables an opti-

mal illumination of each compo-

nent. The gray-scale picture re-

corded is analyzed on the basis of

the algorithm best suited for the

package form.

ICs, Flip Chips and IC-sockets are

centered on the basis over the

leads or bumps. In the case of

chips, bare chips for subsequent

wire bonding and odd-shaped

components, centering is based

on the outside contour (outline

measurement).

A special inspection mode for the

critical IC lead ends (HALE) pre-

cisely determines the lateral lead

bend as well as pitch error and

lead offset. This greatly reduces

the risk of short circuits.

Beyond this, the rotational angle

deviation and the X-/Y-offset of the

component relative to the nozzle

center is ascertained and factored

in during placement. The X-/Y-

offset also results in the correction

of the pick-up position.

In order to have the vision module

center a component which it does

not yet know, it must first be de-

scribed geometrically in the pack-

age form (GF) file. The component

test makes it possible to check at

the station to determine whether

adjustments, in lighting for exam-

ple, are necessary. These adjust-

ments are automatically assigned

as a file to the pertinent package

form which represents a compo-

nent type. Hence they are valid for

all of the stations in a line. As the

final step, the GF number of the

component type is entered in the

component file.

Vision Sensor Technology:

Fine Pitch Component Vision Module for the

Pick & Place Head

Technical Data

Max. component size

32 x 32 mm (single measurement)

55 x 55 mm* (multiple measurement)

Component range

PLCC, LCCC, QFP, SO, BGA, Flip Chip

components with connections up to

55 x 55 mm (J-leads and gull-wings,

balls, bumps)

Camera’s field of view 38 x 38 mm

Illumination

Front light

(3 freely programmable planes)

Analysis algorithms Compare page 25

* Larger components available on request

Description

The Flip Chip component vision

module extends the capability of

processing Fine Pitch and Flip Chip

components with extreme fine

lead pitches. This add-on module

for the Fine Pitch component vi-

sion module offers a far higher

resolution. The lighting layout is

fundamentally changed in the pro-

cess. At optimal illumination, the

imaging of the bumps is as large

as possible and the orthogonal dis-

ruptive structures (e.g., chip

printed conductor tracks) are sup-

pressed. In the event of less pro-

nounced disruptive structures, the

intensity can be increased by

combined lighting. This results in a

high recognition reliability even

with usually square surfaces of

bumped Flip Chips in the conduc-

tive adhesive technology.

Special search algorithms are used

to recognize the bumps (balls) in

surroundings where fault condi-

tions usually prevail.

Vision Sensor Technology:

Flip Chip Component Vision Module for the

Pick & Place Head (Option)

Technical Data

Flip Chip size

with single measurement

with multiple measurement

1 x 1 mm

up to max. 7 x 9 mm

max. 20 x 20 mm

Dimensions < 3 x 6 mm

Special nozzle,

feeding tolerance < 0.2 mm edge length

Min. bump diameter 80 µm

Placement cycle

min. 2 s

(depending on number of bumps)

IC-pitch:

Lead pitch

Bump pitch

0.25 mm

0.15 mm

Camera’s field of view 9 x 11.5 mm

Illumination

Front light

(3 freely programmable planes)

Description

The optional coplanarity check fur-

ther enhances placement reliabil-

ity. This check is always con-

ducted right after the deviation of

position is ascertained with the

Fine Pitch vision module of the

Pick & Place head.

The coplanarity module is installed

next to the PCB conveyor along

with the Fine Pitch vision module

of the Pick & Place head.

One of the biggest problems in

Fine Pitch technology, the copla-

narity of leads, can be largely

eliminated by taking one additional

step during inspection. The copla-

narity module is employed to con-

duct a contactless, sequential ver-

tical scanning of the IC lead

structure on the basis of the laser

triangulation principle. The height

profile thus obtained for all of the

rows of leads is used to calculate

placement plane of the IC. The

programmed tolerance band based

on this placement plane then be-

comes effective.

If even one lead is outside this

placement area, the component is

excluded from the placement pro-

cess. It is gently placed back in the

Waffle Pack, entered on the repair

list and automatically repaired.

The component picked up by the

placement head may be crooked,

e.g., because one surface of the

package is not parallel to the row

of leads. The calculation of the

placement eliminates any influ-

ence this might have on

placement however.

As the result of extensive security

measures, the laser can only be

operated in the closed machine. It

then conforms to Safety Class 1

(not dangerous for eyes and skin).

Barring manipulation of the protec-

tive devices, the laser will not op-

erate outside the machine. Fol-

lowing impermissible tampering,

the laser complies with Class B.

On SIPLACE placement systems

the component which is picked up

is placed on the PCB immediately

after the coplanarity check. This

procedure ensures that no change

can occur after the check as the

result of any subsequent mechani-

cal influence. Unlike other designs,

with SIPLACE machines it is not

necessary to pick up the compo-

nent again or to transport it in a

special pick-up movement.

Vision Sensor Technology:

Coplanarity Module for the Pick & Place Head (Option)

Effects of coplanarity (lateral ben-

ding of leads) of a populated com-

ponent

Accuracy of the coplanarity module

Uncertainty of checking in case of real components

Dimensions

99.73

[µm]*

32 x 32 mm

55 x 55 mm

21.5

22.7

* Checking uncertainty of a single measurement with a confidence interval of 99.73%

(corresponds to 3

)