Schottky barrier

About: Schottky barrier is a research topic. Over the lifetime, 22570 publications have been published within this topic receiving 427746 citations. The topic is also known as: Schottky barrier junction.

Low-Temperature Ohmic Contact to Monolayer MoS2 by van der Waals Bonded Co/h-BN Electrodes

Abstract: Monolayer MoS2, among many other transition metal dichalcogenides, holds great promise for future applications in nanoelectronics and optoelectronics due to its ultrathin nature, flexibility, sizable band gap, and unique spin-valley coupled physics. However, careful study of these properties at low temperature has been hindered by an inability to achieve low-temperature Ohmic contacts to monolayer MoS2, particularly at low carrier densities. In this work, we report a new contact scheme that utilizes cobalt (Co) with a monolayer of hexagonal boron nitride (h-BN) that has the following two functions: modifies the work function of Co and acts as a tunneling barrier. We measure a flat-band Schottky barrier of 16 meV, which makes thin tunnel barriers upon doping the channels, and thus achieve low-T contact resistance of 3 kΩ.μm at a carrier density of 5.3 × 1012/cm2. This further allows us to observe Shubnikov–de Haas oscillations in monolayer MoS2 at much lower carrier densities compared to previous work.

Barrier height inhomogeneities of epitaxial CoSi2 Schottky contacts on n-Si (100) and (111)

Abstract: The forward current–voltage characteristics of epitaxial CoSi 2 contacts grown by Ti-interlayer mediated epitaxy (TIME) scheme on n-type Si substrates of both (100) and (111) orientations are studied in the temperature range from 80 to 300 K At high temperatures (>220 K), the I–V characteristics obey the ideal thermionic emission model The Schottky barrier heights stay ∼061 eV and the ideality factors are close to unity At low temperatures, a change in the characteristics is observed around 10 −4 A/cm 2 , which is more significant for the contacts on Si (111) than for those on Si (100) Above this current, the I–V curves can also be fitted by the equation based on the thermionic emission theory, but the apparent barrier heights decrease and the ideality factors increase with decreasing temperature This abnormal behavior, as well as the curved Richardson plots, are interpreted by the assumption of a Gaussian distribution of barrier heights, which is in agreement with the statistical distribution obtained directly from ballistic electron emission microscopy (BEEM) measurements The excess current at small bias region is explained by coexistence of some small patches of reduced barrier height with the pinch-off model The CoSi 2 contacts on Si (111) contain more patches with larger parameter values than those on Si (100), which causes a significant difference in the I–V characteristics at low temperature

Metal-semiconductor-metal photodetectors based on graphene/p-type silicon Schottky junctions

Abstract: Metal-semiconductor-metal (MSM) photodetectors based on graphene/p-type Si Schottky junctions are fabricated and characterized Thermionic emission dominates the transport across the junctions above 260 K with a zero-bias barrier height of 048 eV The reverse-bias dependence of the barrier height is found to result mostly from the Fermi level shift in graphene MSM photodetectors exhibit a responsivity of 011 A/W and a normalized photocurrent-to-dark current ratio of 455 × 104 mW−1, which are larger than those previously obtained for similar detectors based on carbon nanotubes These results are important for the integration of transparent, conductive graphene electrodes into existing silicon technologies