This is how I did it with 100 micron Cu foil by recrystallizing top surface and used chemical hand polishing method to get very large area monolayer Gr.

1. Annealing 1050 / 1060 CAnnealing time = around 5 hr (Ramping up time = 30 min to 1 hr, Steady temp time = 5 hrs)Gas condition Ar:H2 :: 5:1

2. Chemical polishing:

• Take Cu etchant with different dilutation. At least 4-5 dilutation of Cu etchant with water
• High concentration Cu etchant will smooth up the Cu substrate, but it will oxidized the Cu substrate also
• Rub with diluted Cu etchant to remove the majority of oxide
• Rub with more diluted etchant to romve more oxide
• Reapet these procesess untill all of the Oxide removes and Substrate looks clean and shiny
• Rub with water at the end to remove CuCl3 from the substrate

After these you will get something like this attached image..Good luck..

you can try whit sulfuric acid and hydrogen peroxide (1:1) for a few seconds and after that a quick wash whit sulfuric acid at 10%, it can help you whit the roughness and will eliminate the oxides that could exist on the surface of your substrate and the graphene will grow only on metallic copper

İ Will try it. Thanks for yourself suggestion.

best regards

your welcome,  let know if works, please

We are submitting a work related to that issue. In fact, we found that no mater what treament you do with your copper foil, during the growth process of graphene, the morphology of copper surface will turn back to be rough (due to high temperature in CVD champer). However, it can be more regularily rough if you do specific treatment prior to growing graphene. So, my experience: no solution so far.

Electropolishing can help; Using a counter copper electrode, Phosphoric acid based electrolyte and used your foil as the other electrode. My experience with this technique is that special care should be taken to optimize the conditions not to form pits on the surface of the foil. 

Check out this article

http://csmres.co.uk/cs.public.upd/article-downloads/April-9th-3.pdf

thanks for your suggestion.

dear Javier,

your suggestion is not working vey well. sulfuric acid and hydrogen peroxide (1:1) is very agressive solution. I try it 2s, 5s, 10s, 30s, 60s. but there is very damaged surface.

best regards.

We use ammonium persulfate to etch the copper surface.

I use TCE -> APS -> DI -> Acetone -> IPA. with each followed by N2 drying

This is how I did it with 100 micron Cu foil by recrystallizing top surface and used chemical hand polishing method to get very large area monolayer Gr.

1. Annealing 1050 / 1060 CAnnealing time = around 5 hr (Ramping up time = 30 min to 1 hr, Steady temp time = 5 hrs)Gas condition Ar:H2 :: 5:1

2. Chemical polishing:

• Take Cu etchant with different dilutation. At least 4-5 dilutation of Cu etchant with water
• High concentration Cu etchant will smooth up the Cu substrate, but it will oxidized the Cu substrate also
• Rub with diluted Cu etchant to remove the majority of oxide
• Rub with more diluted etchant to romve more oxide
• Reapet these procesess untill all of the Oxide removes and Substrate looks clean and shiny
• Rub with water at the end to remove CuCl3 from the substrate

After these you will get something like this attached image..Good luck..

Removal of the native oxide from the Cu foil before annealing process (though H2 ambient annealing) will possibly help to improve the surface characteristics.