QuikPak - Wafer Preparation, Unlimited Packing Solutions, Custom Assembly Services

Tech Tips

The following Tips are intended to help guide you through your assembly of Quik-Pak Open-Cavity products.

OCPP Product Storage

Packages must be kept in a dry atmosphere or wrapped in Silver Saver® paper or comparable product until ready to be bonded. This minimizes the formation of silver sulfides (tarnish) on the bonding surfaces. In controlled humidity desiccators, we recommend a nitrogen purge regulated to 4 - 8 SCFM, at a temperature of 68° Fahrenheit, less than 10% RH.

Die Attach

The Quik-Pak standard die attach material is QMI 529 HT. It is a highly silver filled conductive adhesive to provide high thermal conductivity and excellent electrical conductivity for attachment of Integrated circuits to metallic leadframes. Caution should be exercised to insure the epoxy does not bleed out and reach wire bond surfaces. The material should be used sparingly, with little or no fillet.

Quik-Pak does have experience with many other die attach materials, as well. Give us a call if you have a question on a specific material.

Wire Bonding

Quik-Pak open-cavity packages will accept both thermosonic gold and ultrasonic aluminum wire bonding. Wire bonder machine settings must be adjusted to optimize wire bonding quality and reliability. Below are recommended baseline settings for Quik-Pak Open-Cavity packages using 1 mil gold wire. You will have to adjust them according to your bonder and individual package/process requirements. For other wire diameters please call us.

Typical Automatic Bonder Settings

(ESEC 3088iP baseline settings)

1st Bond (die) Force 250 - 300 mN (25 - 30 grams)
   - Time 10 -13 ms
   - U/S power 18-23%
2nd Bond (leads) Force 350 - 700 mN (35 - 71 grams)
   - Time 19 ms
   - U/S power 21-25%

Typical Manual Bonder Settings

(K&S 4524AD baseline settings)

First (Die) Bond Power - 1.3 avg. (range 1 to 2)
First Bond Time - 2.0 avg. (range 1 to 5)
First Bond Force - 1.60 avg. (range 1 to 2)
Second (Lead) Bond Power - 2.95 avg. (range 2 to 3)
Second Bond Time - 3.45 avg. (range 3 to 7)
Second Bond Force - 3.3 avg. (range 2 to 6)

For gold ball bonding, the package temperature should be maintained between 140° to 160° Centigrade. Be sure to adjust your temperature offset allowing for heater block and package thermal resistance to insure the package is within the bonding temperature range.

Mechanical clamping is preferred; however, vacuum clamping can be used with the correct fixturing.

Encapsulation

The standard Quik-Pak encapsulation material is Loctite Hysol FP4653. Quik-Pak does have experience with many other encapsulant materials, including low-K and low stress materials. Again, give us a call if you have a question on a specific material.

Drying

If your product plans include surface mounting of our packages, we recommend that you dry-bake the package at 125° +5/-0° Centigrade for 24 hours prior to PCB assembly. For more information, see IPC/JEDEC Standard J-STD-033.

We understand our package is critical to your products’ success. Do not hesitate to call us if you experience any problems assembling our packages. Our number is 858.674.4676.