You are given a task to solder the chip to a printed circuit board (PCB). In this case, you need to produce a connection between the chip and the PCB to satisfy a couple of criteria. One is to make connections such that the chip is fixed at a given location on the PCB. The second is to enable both heat and electricity to pass through the connection. In this example, we are mainly interested in the thermal quantities, so that if the chip gets heated due to computational efforts, the heat is transferred to the PCB. This thermal analysis is important to understand the performance of the chip and the overall board. To connect these two components, we use a soldering process in which a metal prong on the chip is fitted into a slot on the PCB made of a second metal. We melt a third, filler metal (the solder) so that it flows into the slot and creates a solid connection between the prong and the slot when the solder cools and hardens. For this, the filler metal has a relatively low melting point compared to the other two metals.
In this lesson, we will discuss the thermal contacts that need to be made between different components.
Here are the accompanying handout slides for this lesson.