Escatec offers PoP as low volume option

Martin Muendlein, Escatec's engineering manager, commented: "Until now, PoP has only been used in high volume applications such as mobile phones, where it provides high density packaging, low power and high performance. We believe that we are one of the first contract manufacturers in Europe to offer this as a low volume option to customers." PoP enables one bga package, such as a memory chip, to be soldered on top of another bga, such as a processor. Escatec says the method is ideal for customers wanting to make portable devices that need high performance processors but where space is tight. The company has reportedly invested in a special dipping unit for their new Siplace assembly line to enable PoP. The dipping unit wets about 50% of each ball of the ball grid array with paste/flux. Before reflow, both components are stacked on each other and soldered in one process step. During the soldering the upper device sinks down so that, in the final assembly, there is virtually no gap between the two stacked chips. Verification of accurate bonding between the layers of the PoP stack is checked using x-ray inspection.