Using Carbon Dots or Tape
Carbon conductive adhesive in sheet, tape or dot form is available at Ted Pella, Inc. Here is a link;
Hints and Tips for Using Carbon Dots or Tape
This information is courtesy of superuser Jim Kruger
- Often too sticky for easy removal. This can be mediated by touching 10 gloved fingertips to the dot before mount the chip. This reduces the % adhesive between C grains, reducing the force required for removal. Change your gloves
- Removal is much easier if you heat the carrier + chip on a hot plate to 40 or 50 or 60 C. Use a razor blade or equivalent to gently apply force and be patient, plan ~ 1 minute for the chip to come loose.
- Acetone wipe to clean up carrier wafer and chip backside. Acetone soak works, but can leave C particles. Ultimate clean is O2 plasma if required.
- If mounting for use with e.g. laser endpoint (as at PQuest), place the carrier and chip in a place where you can see a reflection of the ceiling, line up the reflection of a straight line across the carrier + chip to insure the chip is parallel, in one or both axis.
- The C-dots are known to be good to 70 or 80C, use caution (and pre-tests?) for higher temperatures. For example, the HD-PCVD at 100C is too hot for the dots. This may be true of the PT-DSE tool as well.
- C-dots are made for surface science powder analysis so are much cleaner than e.g. Kapton tape. Still, minimize (or eliminate) the dot area exposed to plasma. Full coverage of the chip backside is not necessary, just a significant fraction of the area. This is because any solid material contact is much better that a vacuum interface, or even that a ~ 10 Torr He backside pressure.
- C-dots are convenient but will not be as good for thermal conduction as a much thinner bond of PMMA or resist