Specific Process Knowledge/Thin film deposition/Temescal: Difference between revisions
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===2. ''Testing July/August 2019 by Evgeniy Shkondin and Patama Pholprasit''=== | ===2. ''Testing July/August 2019 by Evgeniy Shkondin and Patama Pholprasit''=== | ||
Deposition of Ti/Au revealed a big number of particles on the wafers. | Deposition of Ti/Au revealed a big number of particles on the wafers. The amount has been heavily reduced by optimizing deposition conditions and choosing the right crucible. | ||
The particles are in fact gold droplets of various size ejected from the melt. | The particles are in fact gold droplets of various size ejected from the melt. | ||
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*Use as pure Au target as possible. | *Use as pure Au target as possible. | ||
*Do not use ceramic crucible, put Au pellets directly into the dedicated Cu heart pocket. W-crucible can be considered (but so far we did not tested it). | *Do not use ceramic crucible, put Au pellets directly into the dedicated Cu heart pocket. W-crucible can be considered (but so far we did not tested it). | ||
*Sweep | *Sweep pattern needs to be optimized so it coveres the bigger area of the target but avoid getting the beam to close to the edges. | ||
*Optimize soak/rise powers and times. | *Optimize soak/rise powers and times. | ||
*Use deposition rate of | *Use deposition rate of 2 Å/s. Ensure that the rise2 power is adequate for that rate. | ||
*Ensure | *Ensure appropriate PID values, since the deposition rate has to be stable during the evaporation. | ||
The full results of the testing can be found here: [[:File:Au issues with Temescal.pptx]]. | The full results of the testing can be found here: [[:File:Au issues with Temescal.pptx]]. | ||