Today’s microelectronic manufacturing environments seem to be constantly changing. One day you are building up traditional “flat-land” ceramic substrates, the next you are laying wire down inside incredibly deep packages. Substrates can be very small for weeks or months, and then you are asked to bond a package that is 6-12 inches square. At times the package designers do not care about loop heights or repeatability. Then there is a need for super low loops, and the wire height and sway must be less than ½ wire diameter (or less.) Also, there must be capability of bonding Tailless or Planar BumpsTM, as well as forward and reverse bonded wires.
Those of us in the microelectronic packaging world must get used to this state of constant change. What one needs and must have is a wire bonder that is flexible, evoking a very large working envelope that allows for very deep access bonding, in addition to resolution and repeatability beyond day-to-day needs. The wire bonder must also be fast and always generate the highest possible reliability in interconnecting wires and bumps. These wire bonders are a rare breed.
Semiconductor vs. Complex Hybrid
The total available markets for first level interconnect are dominated by two main classes of packages. Many call these “semiconductor” and “complex hybrid” or MCM. Most semiconductor wire bonders focus on speed, speed, and speed. They are not good at dealing with changing environments, deep access, large packages, or even alternate dies—but they are fast. They live in the high volume/low mix environment. However, there is another class of bonders that lend themselves to complex hybrids, MCMs, and high-reliability devices. Palomar Technologies’ Model 8000 gold ball bonder/ball bumper lives in this complex market.
The Model 8000 has a very large working envelope, can use a 0.750” capillary allowing for ultra deep access, produces “laser loops” that do not sway or sag, and generates the highest reliability interconnect available. It can generate very repeatable ball bumps and traditional wire bonds in a single program using the same standard wire and capillary. The 8000 Wire Bonder can also use Stand-Off Stitch or security bonds and produce running chains (stitch-stitch), or a combination of all three.
In addition, wires as long as 500 mils can be generated and very large 1st to 2nd bond heights can be accommodated. We can heat the tool if we cannot heat the part—up to almost 150°C—or we can increase the ultrasonic frequency to allow for less than optimal bond site temperatures. Hot gas manifolds can preheat difficult packages prior to presenting them to the bonding envelope. The 8000 has a very small clean room floor footprint, and uses typical clean room facilities. A wide variety of materials handling systems are available; otherwise there are very few limits to the more traditional manually loaded and unloaded tooling systems.
Continuous Bonding Technology
If a program were to shift into a higher volume, lower mix situation the Model 8000 can use what is called “continuous bonding technology”. This is where the material handling system keeps materials presented to the bonder, either manually or fully automatically in such a fashion that the bond head never (or rarely) stops doing what it was designed for–non-stop wire bonding.
If your needs intersect the complex microelectronic market, chances are that a Model 8000 Wire Bonder could be necessary for your packaging requirements.
Regional Account Manager, Western Americas
Palomar Technologies, Inc.