Specific Process Knowledge/Etch/DRIE-Pegasus/picoscope: Difference between revisions
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# What happens if the cycle duration is lowered in order produce smaller scallops? | # What happens if the cycle duration is lowered in order produce smaller scallops? | ||
# How do we know if something that is very brief happens? For instance, spikes in reflected power can be rather short lived as indicated by the one point spikes of reflected coil power above. | # How do we know if something that is very brief happens? For instance, spikes in reflected power can be rather short lived as indicated by the one point spikes of reflected coil power above. | ||
In both cases, the sampling rate 2 samples per second is simply not high enough - we need to increase this. The SPTS Pro software can only lower this. However, realizing that all | In both cases, the sampling rate 2 samples per second is simply not high enough - we need to increase this. The SPTS Pro software can only lower this. However, realizing that all the devices (mass flow controllers, pressure gauges, RF generators etc.) responsible for the parameters in the plot above are producing output measurements in real time, we can sample these parameters by probing them with some external device. Enter the | ||
[https://www.picotech.com/oscilloscope/4824/8-channel-oscilloscope Picoscope oscilloscope] with 8 analog channels that enable us sample up to 8 outputs, usually a DC voltage, at almost any sampling rate. Unlike the old oscilloscopes, the Picoscope is fully operated by a software that produces a vast amount of data and nice plots. We therefore have to decide which process parameters are the most important to monitor and then go through the electrical diagrams to find an appropriate place to pick up the signal. This set of parameters is chosen as shown in the plots above. | [https://www.picotech.com/oscilloscope/4824/8-channel-oscilloscope Picoscope oscilloscope] with 8 analog channels that enable us sample up to 8 outputs, usually a DC voltage, at almost any sampling rate. Unlike the old oscilloscopes, the Picoscope is fully operated by a software that produces a vast amount of data and nice plots. We therefore have to decide which process parameters are the most important to monitor and then go through the electrical diagrams to find an appropriate place to pick up the signal. This set of parameters is chosen as shown in the plots above. | ||