During the last year, the importance of semiconductors and the fragile balance between supply and demand became clear. Chip shortages are propelling manufacturers to make new investments in the semiconductor failure analysis process, so they can accelerate yield learnings and process improvements, and better meet demand.
As companies install new instruments and technologies in their labs and fabs, it is important they also minimize environmental interference and other factors that may result in suboptimal instrument performance.
Vibration, created by internal and external sources can stem from HVAC equipment, construction, or even foot traffic. Acoustic noise sources can include air handling systems and people talking. EMI can find its way into systems from transformers, subways, and other electric sources in the area.
Case study: when environmental interference causes image distortion
While many companies consider the implications of floor vibrations in the site preparation process, it is also important to consider acoustics, electromagnetic interference (EMI) and other vibration sources.
Environmental factors can negatively impact semiconductor failure analysis productivity, as outlined in a real-world case study from Thermo Fisher Scientific.
Approximately five years ago, while working with customers at our NanoPort in Hillsboro, Oregon, we noticed significant image distortions in our Helios 4 FX DualBeam system.
In fact, the images were of such poor quality that we were unable to perform accurate analysis, and it forced us to suspend the work we were doing with our customer.
This major inconvenience caused a full investigation to get to the root cause of the issue.
Working with our Site Preparation Services team, we initiated a comprehensive site survey of our NanoPort and the surrounding area.
We performed vibration, acoustic and electromagnetic interference (EMI) measurements, as well as a beam analysis to match the frequencies to their source and quickly determined it was a vibration issue.
Our investigation led us here, where we identified the source as environmental interference:
Mitigation solutions to enhance the semiconductor failure analysis process
Since we couldn’t stop the construction, nor could we move our lab, we focused on targeted mitigation steps to allow us to resume our work.
First, we performed our work during “off” hours. In conducting our site preparation survey, we discovered the construction work ended each day at 5:00 p.m. and the vibration issues disappeared. Employing this step allowed us to resume work while we planned our long-term fix.
Then, we engaged with TMC, a global supplier of vibration isolation products, to develop a custom, active vibration isolation platform —the TMC SEM-Base LP for Thermo Fisher. Once installed, the vibration issue was resolved, and we were able to quickly get our system back in action.
Planning ahead for environmental interference
Vibration, acoustics, and EMI can all affect semiconductor failure analysis instrument performance.
These environmental interference sources can cause a variety of negative effects on the semiconductor failure analysis process, including image distortion, a loss of resolution and data, and zero loss peak instability—making it virtually impossible to perform critical failure analysis work. System downtime can negatively impact failure analysis, yield learning and process monitoring work.
For those building new or redesigning existing labs and fabs, the best time to mitigate environmental interference is before the build or redesign of a lab or fab, or before the installation of an instrument. Conducting a thorough site preparation survey can identify several actions you can take to mitigate the impact of environmental factors before they disrupt operations.
Visit our Site Preparation Services webpage for additional information.
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David Akerson is a Senior Global Market Development Manager for semiconductors at Thermo Fisher Scientific.
shine_Chung says
Hi,
I have questions about using SEM in semiconductor failure analyses.
(1) If a silicided poly misses part of all the silicided on top, can this defect be detected by SEM? The poly has W/L=0.18/0.9um.
(2) If a copper interconnect in 12nm (W=32nm) have copper missing inside the liner/cap so that there would be a sagging. Can the SEM detect this?
Thx.
Shine