PMID- 20110580
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20100525
LR  - 20100208
IS  - 1361-6528 (Electronic)
IS  - 0957-4484 (Linking)
VI  - 21
IP  - 9
DP  - 2010 Mar 5
TI  - Investigations of niobium carbide contact for carbon-nanotube-based devices.
PG  - 095201
LID - 10.1088/0957-4484/21/9/095201 [doi]
AB  - Single-walled carbon nanotube (SWCNT) field effect transistors (FETs) with Nb 
      contacts have been fabricated and upon annealing in vacuum at 700 degrees C for 1 
      h, niobium carbide (Nb(2)C) is formed at the Nb/SWCNT interface. The Nb(2)C/SWCNT 
      contacts demonstrate a very small Schottky barrier height of approximately 18 meV 
      (decreased by > 80% relative to that of pristine Nb/SWCNT contact of 
      approximately 98 meV) to p-type transport. This is attributed to the higher work 
      function of Nb(2)C (approximately 5.2 eV) than Nb (approximately 4.3 eV) and 
      better bonding between Nb(2)C and SWCNTs. The performance of Nb(2)C-contacted 
      SWCNT FETs is as follows: the p-channel ON current is as high as 0.5 microA at 
      V(DS) = 0.1 V, the I(ON)/I(OFF) ratio is up to approximately 10(5) and the 
      subthreshold slope is approximately 550 mV/dec, which is as good as that of 
      titanium carbide (TiC-) and Pd-contacted SWCNT FETs. Compared with TiC, Nb(2)C 
      contacts yield more unipolar p-type SWCNT FETs, as a result of the Nb(2)Cs higher 
      work function. More importantly, Nb(2)C contacts can form near-ohmic contacts to 
      both large-(>or=1.6 nm) and small-diameter (approximately 1 nm) SWCNTs, while Pd 
      can only form near-ohmic contacts for large-diameter SWCNTs. Moreover, the Nb(2)C 
      contacts demonstrate good stability in air.
FAU - Huang, L
AU  - Huang L
AD  - Centre for Optoelectronics, Department of Electrical and Computer Engineering, 
      National University of Singapore, Singapore, Singapore. g0403704@nus.edu.sg
FAU - Chor, E F
AU  - Chor EF
FAU - Wu, Y
AU  - Wu Y
FAU - Guo, Z
AU  - Guo Z
LA  - eng
PT  - Journal Article
DEP - 20100129
PL  - England
TA  - Nanotechnology
JT  - Nanotechnology
JID - 101241272
EDAT- 2010/01/30 06:00
MHDA- 2010/01/30 06:01
CRDT- 2010/01/30 06:00
PHST- 2010/01/30 06:00 [entrez]
PHST- 2010/01/30 06:00 [pubmed]
PHST- 2010/01/30 06:01 [medline]
AID - S0957-4484(10)35865-X [pii]
AID - 10.1088/0957-4484/21/9/095201 [doi]
PST - ppublish
SO  - Nanotechnology. 2010 Mar 5;21(9):095201. doi: 10.1088/0957-4484/21/9/095201. Epub 
      2010 Jan 29.