The research leading to these results has received funding from the French Agence Nationale de la Recherche, grant ANR-15-CE40-0006 (CoMeDiC), the Brazilian Federal Agency of Support and Evaluation of Postgraduate Education (program CAPES/PVE: grant 064965/2014-01), Brazilian Federal Agency of Research (CNPq/Universal 421521/2016-3 and CNPq/PQ 307062/2016-3), Fundo de Amparo Pesquisa do Estado de Minas Gerais (FAPEMIG/PPM 00006-16), the Peruvian agency Consejo Nacional de Ciencia, Tecnológica CONCYTEC (contract N 101-2016-. FONDECYT-DE). The first author would like to thank Brazilian agencies CNPq and CAPES and Peruvian agency CONCYTEC for the financial support during his thesis.

We wish to thank Laurent Pham-Van (CEA/IRAMIS/SPEC/LEPO) for fruitful discussions on the tip etching process and Sylvain Foucquart (CEA/IRAMIS/NIMBE/LIONS) for his technical assistance. José Antonio Morán Meza would also like to acknowledge financial support from the Peru’s National Council of Science and Technology (Concytec), the Réseau Thématique de Recherche Avancée (RTRA-Triangle de la Physique), and the CEA/Direction des Relations Internationales (DRI).

This work received funding from FONDECYT-CONCYTEC (contract number 004-2016-FONDECYT), CAPES (PVE 125000/2014-00), FAPEMIG (PPM 00006-16), and CNPq (Universal 421521/2016-3 and PQ 307062/2016-3).

The fabrication of ultra-sharp tips from carbon fiber (CF), which are mounted on a qPlus probe for combined dynamic scanning tunneling microscopy (STM) and frequency modulation atomic force microscopy (FM-AFM) experiments, is reported. The carbon fiber tips were electrochemically etched in a KOH or NaOH solution, using different electronic devices. CF tips with an apex radius ∼10 nm, as deduced from the measured slopes of the Fowler–Nordheim plots (kR < 70 nm for k ∼ 6), were routinely obtained with a homemade electronic device that controls the intensity of the etching current. Then, these conductive CF tips were also characterized by imaging the 6H-SiC(0 0 0 1) surface covered by an epitaxial graphene layer in ultra-high vacuum (UHV). The lattice of the R30° reconstruction was regularly imaged by STM working either in non-oscillating mode or in dynamic mode, which also maps the ...