As we have to qualify the HBM/MM/CDM sensitivity levels for device(ICs) by using equipments which simulate real world discharging situation following ANSI/ESDA/JEDEC standards and each standard have instruction to use bandwidth 1G or 6G oscilloscope to measure signal, I wonder that what’s the characteristic of discharge signal of HBM, CDM, MM ? Have approximate value?
Characteristic includes: rise time, bandwidth, total discharging time and so on.
To my understanding, before we choose a meter to catch signal, we have to know signal’s nature.
One thing to mention is that MM is no longer required for module qualification. That standard practice has not been update for a while and is for reference only. HBM or CDM standards have the scope requirements and the required measurements to verify the waveform. They also include the test setup for verification. Is there something specific that is needed outside the standards?
The quick answer, 6 Gig might not be fast enough to capture a CDM event. The reason for 6 Gig and 1 Gig is cost. When the standard was first written, the cost of equipment was very high. The decision was what could be done with to ensure repeatability and reproducibility at a reasonable cost.
To tell you the truth, I’m not sure. I don’t think that anyone knows how fast the CDM waveform really is. I will see if I can find out the answer and post it later. I would also encourage you to attend the CDM and HBM virtual committee meetings. The schedule for the meetings is on the ESDA website. They are all virtual and open to anyone.
John
I just spotted your communicatin with John and thought I might give you an idea about the effect that a high-BW scope can have on the captured CDM waveform. I have captured CDM waveforms of a given CDM tester with a 1 GHz, a 6 GHz and a 12 GHz scope. While a 6 GHz scope reveals mainly larger amplitudes than a 1GHz scope, a 12 GHz scope may show you even the ringing superimposed by the given CDM test head over the waveform captured by the 1/6 GHz scopes and specified in the standard.
If you plan to do some research on CDM waveforms, I recommend to go for the highest BW you can affort. However, if you “only” plan to run CDM qualification tests of semiconductor devices, just use a 6 GHz scope.