Field emission energy distribution and three-terminal current-voltage characteristics from planar graphene edges

Abstract

We demonstrate field emission from an integrated three-terminal device using a suspended planar graphene edge as the source of vacuum electrons. Energy spectra of the emitted electrons confirm the field-emission mechanism. The energy spectra produced by graphene grown by chemical vapor deposition and reduced graphene oxide are compared. The drain-source voltage required to produce a given drain current increases when negative voltages are applied to the gate, confirming field-effect transistor operation. The emission current rises exponentially with inverse voltage over the measured current range from 1 pA to 10 nA. The current-voltage characteristics are consistent with tunneling through barrier potentials calculated numerically from the device geometry.

Narrow energy distributions of electrons emitted from clean graphene edges

“…The tempera- ture reduction was estimated [40] to be only about 60 to 70 K due to poor thermal conductivity of our setup. Our spectra are ∼2-3 time narrower than a metallic emission peak, ∼15 time narrower than previous measurements on graphene [13], six times narrower than one of the theoretical value [19] and 3 time larger than the other [20], which is surprisingly narrow at ∼0.06 eV, to our knowledge only once achieved for FE in any experiment [43]. A final point is that our individual peaks all have the asymmetric form characteristic of tunneling from a metal through a triangular barrier which is not the case of the theoretical prediction whose peaks do not appear to have a high energy temperature edge.…”

“…In Ref. [13] peak widths of ∼2 eV were shown that shifted to lower energy with increasing applied field. On the theoretical side there is an increasing body of work on FE from graphene edges [19][20][21][22][23][24][25] and reference therein of which two predict the energy distribution [19,20].…”

“…Graphene, a subject of great interest for many domains of science and technology, has logically been considered for field emission (FE) sources simply because its single atomic edge has potentially nature's highest enhancement of electric field, thus opening perspectives for low voltage vacuum nanoelectronics. Though considerable work has been done [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] there is a dearth of measurements on well-characterized, individual single sheet graphene layers that can guide the community towards future developments. The published work is primarily on multiemitter films or individual multilayer emitters (see Ref.…”

“…The total energy distributions (TEDs) of the emitted electrons are of particular interest because they give access to the density of states near the Fermi level and thus of the graphene edge and corner states which is a very active research domain [17,18]. Only two measurements [12,13] of the energy distributions of emitted electrons from uncleaned edges covered with multilayer graphene have been reported. In Ref.…”

Ρεύματα Εντός Νανοηλεκτρονικών Αισθητήρων Και Νανοηλεκτρονικών Τρανζίστορ Κενού

“…1.6 Κατανομή ενέργειας εκπομπής πεδίου και χαρακτηριστικές ρεύματος-τάσης από επίπεδες ακμές γραφενίου Η εκπομπή πεδίου από τις ακμές του γραφενίου που κατασκευάζονται σε επίπεδα υποστρώματα μπορούν να χρησιμοποιηθούν ως πηγές ηλεκτρονίων για ηλεκτρονικές συσκευές κενού, με τη μεταφορά να γίνεται παράλληλα με την επιφάνεια του υποστρώματος. Αυτή η ομοιόμορφη αρχιτεκτονική που αναπτύχθηκε από την ομάδα των Jonathan L. Shaw , John B. Boos, Byoung Don Kong, Jeremy T. Robinson και Glenn G. Jernigan, όπου όλα τα ηλεκτρόδια είναι διαμορφωμένα σε ένα κοινό επίπεδο υπόστρωμα χρησιμοποιώντας απλή λιθογραφία, επιτρέπει την εύκολη ενσωμάτωση και επεκτασιμότητα παρόμοια με τις συσκευές στερεάς κατάστασης [11]. Το γραφένιο έχει εξαιρετικά υψηλή θερμική αγωγιμότητα, μηχανική αντοχή και χημική σταθερότητα, οι οποίες αποτελούν βασικές απαιτήσεις για μια επιτυχημένη πηγή εκπομπής πεδίου.…”