Description of a solder pulse generator for the single step formation of ball grid arrays
- Sandia National Labs., Albuquerque, NM (United States). Materials and Process Sciences Center
The traditional geometry for surface mount devices is the peripheral array where the leads are on the edges of the device. As the technology drives towards high input/output (I/O) count (increasing number of leads) and smaller packages with finer pitch (less distance between peripheral leads), limitations on peripheral surface mount devices arise. The leads on these fine pitch devices are fragile and can be easily bent. It becomes increasingly difficult to deliver solder past to leads spaced as little as 0.012 inch apart. Too much solder mass can result in bridging between leads while too little solder can contribute to the loss of mechanical and electrical continuity. A solution is to shift the leads from the periphery of the device to the area under the device. This scheme is called areal array packaging and is exemplified by the ball grid array (BGA) package. A system has been designed and constructed to deposit an entire array of several hundred uniform solder droplets onto a printed circuit board in a fraction of a second. The solder droplets wet to the interconnect lands on a pc board and forms a basis for later application of a BGA device. The system consists of a piezoelectric solder pulse unit, heater controls, an inert gas chamber and an analog power supply/pulse unit.
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 446381
- Report Number(s):
- SAND-97-0001; ON: DE97004346; TRN: AHC29706%%87
- Resource Relation:
- Other Information: PBD: Feb 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Method and apparatus for jetting, manufacturing and attaching uniform solder balls
Method and apparatus for jetting, manufacturing and attaching uniform solder balls