The XY Theta indexing table: a solution to restricted movement in wire bonding.

• Our assignment was to be able to carry out bumping on 125 mm diameter silicon wafers, while the original equipment working area did not enable the whole wafer surface to be covered.

• The solution we selected enabled the workpiece to be presented on line, without the operator having to move the substrate between programs. The solution was especially effective in avoiding vibration interference which might affect the stabilization time between movements.

To achieve this, we had to design a presentation system where the centre of gravity was constantly in the surface of the table in order to avoid overhang, at the same time ensuring the indexing the whole workpiece. of the part.

Our design is based on a three axis presentation system:

• An X axis,
• A Y axis,
• A Theta axis.

This design enables processing of the first half of the substrate, after a 180° rotation of the part, the second half.

The X axis is a classic design (recirculating ball screw an slider).
The Y axis is linear stepper motor.
The Theta axis is rotary stepper motor.

The results enable us to achieve our assigned objective with total precision.

This experience now enable us to offer new testing and pilot production opportunities for our customer's existing machines. In addition, we have adapted this innovation to other applications in order to be able to process substrates, with or without rotation, where the sizes exceed the capacity of the machines being used.

Creation of an automatic line for processing contactless smart cards (RFID, TAG)

Our assignment was to integrate and develop a turnkey production line for contactless smart card using wide tape.

The line include two main areas:

• Die bond & cure,
• Wire bond & encapsulation.

To create such line a close co-operation between four equipment suppliers was required :

• Die bonding machine,
• Wire bonding equipment,
• Encapsulation unit,
• UV cure station (manufactured by Caléo Engineering).

Caléo Engineering alsodeveloped the missing links in the line :

• Tape winders/unwinders,
•Indexers.
The overall integration of the various equipment.

As each equipment has different characteristic the Caléo Engineering items, and especially the indexers had to be designed for each machine in intimate co-operation with each of the other OEM's project engineers.

This contact demonstrated Caléo Engineering's ability to adapt to specific cases within reasonable deadlines. Thanks to this our customer retained that vital edge in response time required for placing its product on the market.

Substrate spool handling

The assignment was to able to manage substrate handling (35 mm smart card film) which comes in continuous lengths wound on spools as well as to ensure management of the separator strip.

The overall design broke was brokes down into two distinct blocks:

• The input arm
• The output arm

These two autonomous assemblies can either be mounted as part of the equipment or as a stand-alone station.

The Input Arm
Made up of two spool holding shafts.

• One curbed shaft to take the full spool for unwinding the film,
• One motorized shaft, slaved to a photo detector, to take an empty spool for winding on the separator strip.

The output arm
Made up of two spool holding shafts.

• One curbed shaft to take spool for unwinding the separator strip,
• One motorized shaft, slaved to a photo detector, to take an empty spool for winding on the film.

Originally designed to handle 35 mm smart card film, this concept has found another lease of life with the arrival of new contactless type substrates (RFID, TAG). This has lead to scale up of the original concept to cope with much larger spools in terms of both weight and size.

The range now extends to spools of up to 800 mm in diameter, and for films of 35 to 400 mm in width.

This solution has offered other customers the opportunity to use existing machines (retrofit) or new generations of a still developing technology.

Tape indexer

The assignment was to offer continuous handing and indexing subsystem for a range of substate widths.

The overall design breaks down into two distinct blocks :

• The static workholder,
• The mobile clamping mechanism

Both assemblies can be mounted on one single plate, or be completely separated depending on the quantities and constraints imposed by the equipment receiving this system.

The static workholder, based on a vacuum plate, holds the film in place during the process.

The mobile rigs, through its transverse clamp film halting system, enable film indexing. This assembly is mounted on a linear motor which can be programmed in accordance with the indexing pitch.

To cope with the problem of the differing film widths that can be processed on this subsystem, it is equipped with adjustable width front and rear guides.

Depending on the type of film used, the indexer assembly can be found in varying versions :

• Mobile workholder and static clamp,
• Transversal or lateral clamp.

The flexibility of the system has thus enabled us to offer a reliable solution to a wide range of customers.