Leak Testing for Integrated Circuits
If integrated circuits are not packaged properly, they may be brittle and fail. Even shock-resistant circuits must work within a very narrow range of restrictions. In this article, we examine how the failure analysis technique would need to pay particular attention to whether and to what degree the electronic component packaging is affected. There are numerous ways to determine the loss of package integrity, and one test we use to do so is fine and gross leak detection.
By requiring specific environmental conditions, one of the techniques to ensure the integrity of chip operations can be used. Operations may be benefited or hindered by elements like humidity, dust, and the presence or absence of trace gases. This necessitates packaging the circuits in sealed containers. We’ve already seen that to access a package’s contents for testing, we occasionally need to open or decapsulate it.
We may need to evaluate the package’s effectiveness in keeping out dust and gases before decapsulation. This necessitates that we go forward without destroying it. There are several such methods, some of which are improved versions of the tests we often run. For instance, if we submerge an inflated bike tube and watch for bubbles, we know there is a leak. We can easily see the source of the leak thanks to the bubbles.
We employ a slightly modified version of this straightforward technique to find significant leakage in integrated circuit packages. For accuracy, a fluorocarbon compound is used in place of water.
But because helium has the unusual ability to pass through even the smallest cracks, we use it to detect incredibly minute leaks. Since the helium can become trapped in surface pockets and escape during the detection phase, leading to a false conclusion of a crack, the tests must be properly conducted. But if there is one, we may use a mass spectrometer to ionize the helium atoms, send them through a magnetic field, and collect them as they emerge to identify the minute amounts of helium that escape. The number of ions and the pace at which they escape can be used to estimate the size of the leak using a kind of electrical current.
Leak testing can be carried out in a variety of ways, including fine and gross leak testing. There are further approaches, which we’ll discuss in upcoming posts.
