When analyzing the various things which can go wrong with an Integrated circuit, we can classify them in two ways. This classification helps in gaining a more comprehensive overview of the inner workings of a chip and the methods used to analyze it. The first way of classification is by the type of IC defect. For example, the problem can lie with the construction of the chip. Presence of voids, improper soldering and cracks in the material are some of the many ways a chip can be defective. These problems can arise at the time of manufacture or they can occur afterwards. Chips can also fail due to electrical defects. Some of these defects can be caused by the first type of error, but it need not be that way. Electrical defects are difficult to find and isolate due to the mind numbing complexity of the circuitry on an IC.

Next, we can have defects based on the purity or impurity of the material comprising the chip itself. The operating conditions of an integrated circuit are very delicate and the purity of the materials is of paramount importance. A deviation by even a fraction of a percent can skew the operating parameters and lead to an IC defect.

Classification of Methods

Failure analysis methods can also be classified based on the type of techniques used. For example, emission spectroscopy covers a wide range of techniques which can be used to discover a host of facts about the specimen in question. Using spectrograph techniques, we can analyze the composition of a wide range of materials and get truly sensitive measurements. This can even be used to obtain certifications to declare that the materials are free from hazardous substances as per the ROHS directive.

X-Ray and Infrared imaging allows us to view the chip from a variety of angles and perspectives to give us pictures we don't see with the naked eye. For example, we can detect minute hot spots which tell us about deviant electrical activity or look inside the chip to detect its workings.

Finally, we classify techniques by whether they destroy the chip or not. Destructive techniques involve opening up the package to expose its innards and get visual confirmation of a suspected flaw if such a thing is possible. Sometimes it's the only way to expose a flaw when all other methods fail. It's a last resort because we'd rather not destroy the chip.

There are some of the ways we can classify an IC defect depending on the type of error or on the type of method used to detect it.

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