Computers used to take up entire rooms to perform what we would consider today rather rudimentary calculations. As computing power increased, the size of the computers decreased. What was once an easily spotted blown tube transistor became very difficult to see electron leakage through a PNP junction.
Enter the world of microelectronics. Every mobile electronic device today is powered by microelectronics. They need to be small, fast and reliable. They also need to be durable. When things go wrong with them, we want to know what caused the failure and how it can be fixed to make our electronics as reliable as possible.
What Are Microelectronics?
An understanding of where microelectronics might fail begins with an understanding of what microelectronics are. In short, microelectronics are circuits that are constructed at the micrometer-scale, perhaps even smaller.
The heart of every computer is the transistor. An easy way to think of it is the more computing power you wish your computer to have, the more transistors you need in its CPU. This means that in order to make a more powerful computer but keep the size of the computer the same, there is a need to figure out a way to make transistors smaller and smaller; enter semiconductor devices.
How We Make Transistors From Semiconductors
As computers advanced and the demand for computing power increased, it became necessary to figure out a way to create a transistor out of something that could be very small. Engineers were able to figure out a way to create the effect of a transistor by using a combination of metals and semiconductor materials.
Transistors created using this method are the foundation of the integrated circuitry controlling all of our electronic devices today. They are made using complex fabrication techniques that allow engineers to make transistors so small they cannot be seen by the naked eye.
When Things Go Wrong
Inevitably, as with any production method, things can go wrong. When this happens, chips and devices fail. This is where the need for accurate failure analysis comes in to play. In order for engineers to understand the causes of the circuit failure, special equipment and experts in using that equipment are needed to do a detailed analysis of the broken part.
There are quite a few places that microelectronics can fail:
- Fabrication Process Failures – these are generally defects that exist when the circuit is created. Complex chemical and electrical processes are used to create microelectronics on a small scale. Small impurities in the materials, the wrong concentration of etching or cleaning chemicals, or plasma etching process issues- all of these can contribute to manufacturing problems which cause IC and device failure.
- Operational Parameter Issues – Issues like this could be design flaws that allow voltages or currents too high for ICs to handle. Things like high operating temperatures or shock damage that exceeds what the IC can withstand are other examples of operational parameters. Evidence of all of these can be seen using the right analysis techniques.
- Design Flaws – These are issues with the circuit itself not performing up to specification due to an improper layout.
- Knowing how to look is a skill. Labs who are experienced with microelectronic failure analysis have a feel as to where in the circuit to begin their investigation. This can save time and money on the device manufacturer’s part as the flaw will be spotted sooner. This means using the right equipment to do the imaging, using the right processes to take a cross-section of devices if needed, and how to interpret the results.
- Knowing where to look is as important as knowing how to look. Experienced technicians will be able to have a feel where inside the IC that these types of failures can occur and look in the right spots sooner than less experienced labs.
Imaging and Failure Analysis
Once the device fails, the investigation into what caused the failure begins. This is where the experts come into play. Choosing a lab that has both the necessary equipment and expertise in the area can be the difference between spotting a flaw and fixing it, or having to scrap a design and go back to the drawing board.
Failure Analysis on the micro scale is not something that is done easily. Remember, these devices are small- so small that even regular microscopes are not able to see them in some cases. This means two things:
As you can see, microelectronics can be complicated devices. When trying to determine the root causes of failure, failure analysis experience is key. Choose an electronics failure analysis lab that has the right equipment and experience in the field. Spirit Electronics is here to help you decipher what is needed to solve your problem.