A Visit to Production Line

The production line in Fresscale is mainly about assembly and packaging.

So the concern of R&D is also about the wafer saw, wire bonding, molding

which is from front end to the back end.

This is the bunny suit that we have to wear in order to get into production line.

Basically this is the process chart from front to back end:

First Step: Wafer Mount

- Process of providing support to the wafer to facilitate processes from “Wafer Saw” to “Die Attach”

- Wafer and wafer frame attached on a film

- Things to be prevented:

Ø Wafer cracking

Ø Bubble trapping on adhesive side of tape

Ø Scratches on active side of wafer

Ø Non uniform tape tension

Step 2: Wafer Saw

- Process that cuts wafer into individual dies

Step 3: UV Cure

- Reduce the stickiness on the adhesive side of the tape

Step 4: Die Attach

- Processing of attaching the die to the die pad of the support structure

- Adhesive die attach is the process used using epoxy as the adhesive agent

Step 5: Curing

- To harden the epoxy to form a stronger bond hold with the die

- Done in an oven

Step 6: Wire Bonding

- Process that provides electrical connection between the silicone chip and external leads using bonding wires

- Wires are usually made of Gold (Au)

Step 7: Molding

- Is a process of encapsulating the device in a polymer material

Step 8: Post Curing

- The molded material is then sent for further curing in an oven

- Oven settings:

¡ About 5 hours curing time

¡ 175°C

Step 9: Marking

- Is the process of putting identification, traceability and distinguish marks on IC package (device name, company logo, date code, lot ID)

- Molded compounds are laser marked

Step 10: Cutting

- Leadframe goes through a series of shearing and displacement tools which acts to cut and separate the individual IC units

- LGA units are conventionally sawed to isolate the individual units

- Units are then punched out or picked and placed into their respective container slots

Step 11: Packing

- Lots are bubble wrapped and strapped together

- Depending on types of units/customer request, some units are dry vacuum packed

- Packed units are put into a shipment box

Step 12: Shipment

- Ready lots are shipped out to customers or other departments for further testing