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Dear BACON participants,

Motivated by discussion among PI's and the aim to help research
progress, we are organizing a monthly graphene fabrication meeting at
MIT and Harvard. This meeting will be run by students and postdocs who
share common concerns regarding issues in graphene nanodevice
fabrication.

Participants are welcome to share their experience or volunteer to
study some of the problems and come back with results. In order to
make the effort most useful and accessible to everybody, the results
presented must be supported by facts. i.e. more quantitatively than
qualitatively.

This Friday, after the BACON meeting, we will gather briefly (most
likely in the same room as Bacon) to discuss more about the format of
this meeting and lay down the issues to be studied in the future
meeting.

Suggested topics for Graphene Fabrication Meetings:

1) Decreasing contact resistance:

Right e-beam dose to minimize residue after development.
-Development times. Test: AFM before spinning and after development.
Pumping before evaporation: Heating? How long? Outgassing issues?
Is UV ozone before evaporation good? Does it damage graphene? What
parameters (direct UV exposure, dark exposure, time, etc)?
What metals work best? Under what conditions?

2) Suspending graphene and gates:

CPD or not?
Electrode thickness and metals?
How to prevent rippling (best geometry)?

3) Graphene quality:

Are different sources of graphite equally good?
Substrate cleaning recipes
Deposition strategies
Current and/or heat annealing? Recipes and parameters.
CVD versus exfoliated graphene

4) Etching and nanoribbon formation O2 or Ar plasma? PMMA, HSQ, and other masks
Catalytic methods (Ni and other nanoparticles, etc)

5) Dielectrics (substrates, ALD, e-beam deposited, etc)
How to improve SiO2?

How to get ALD to work reliably (NO2 functionalization? thin oxide seed?)?
Does high-K really improve mobility?

6) Lift-off issues and after-lift-off cleaning

Best lift-off recipes, best solvent? (warm/cold acetone, other
resist strippers?)
After lift-off cleaning: annealing in forming gas, what temperature,
how long? What happens to contacts?

Looking forward to seeing you this Friday.

Best regards,
Joel I-Jan Wang