The temperature forcing probe is a washing machine sized box with an adjustable arm extending from it. At the end of the arm is a small test chamber. The machine can generate a temperature controlled stream of air, with temperatures ranging from -65ºC up to 185ºC. The test chamber is placed over the part, and the air is used to either heat or cool the part. Then we can measure the parts performance at a given temperature. And it has an auxiliary thermocouple that can be placed on the part to precisely control the actual part temperature.
We do this for several reasons. When a new part comes out, we characterize its performance over the intended temperature range. Not only does this confirm the correct operation of the part, it also provides feedback for our design models. We also use the probe when we need to test production parts at temperature and do not have a temperature handler capable of working with a specific package. And finally, we use the probe for failure analysis when a customer reports a problem at a specific temperature.
One issue with the probe is that it will also heat the tester that holds the part. We have learned that the best solution is to use a small extender cable so that the part under test is not directly on the tester. In those cases, where the part must be on the tester, we use sheets of thermal rubber as a top insulator, and then put multiple layers of cardboard under that to protect the tester from overheating. We tried ceramic tiles at one point for the underlying insulation, under the belief that if they worked for the space shuttle, then they would work for us as well. But they did not work as well as the cardboard, and so that is what we use.
The temperature forcing probe is a strong asset allowing us to provide a superior product for our customers.