Electrical characterization of nanocrystalline carbon–silicon heterojunctions

Abstract

Articles you may be interested inElectrical transport through heterojunctions of single-walled carbon/silicon carbide/carbon nanotubes Electrical conduction and electroluminescence in nanocrystalline silicon-based light emitting devices Band offsets and transport mechanisms of hydrogenated nanocrystalline silicon/crystalline silicon heterojunction diode: Key properties for device applications Nanocrystalline carbon ͑nc-C͒ films were grown by magnetron sputtering on n-type Si substrates at room temperature and at substrate bias voltage Ϫ200 V. The electrical transport properties of nc-C/n-Si heterojunctions are investigated by current-voltage measurements at various temperatures and capacitance-voltage measurements at room temperature. The results indicate that the forward conduction is determined by thermionic emission over a potential barrier of height 0.3 eV at temperatures above 180 K. At lower temperatures and low currents, multistep tunneling current dominates. At low reverse voltages, the reverse conduction is dominated by current generated within the depletion region, while at higher voltages the current is due to Poole-Frenkel emission.

Demonstration of an amorphous carbon tunnel diode

“…2͒. 5 From these analyses we understand that in addition to Schottky barrier emission, tunneling contributes to the total current, which depends on both b and t in the present devices, unlike what was previously suggested for DLC films ͑see Fig. 3͒.…”

“…5,6 Previously, by employing insulating DLC films or metallic graphitic films, heterojunctions have been created on crystalline silicon.…”

“…5,6 Previously, by employing insulating DLC films or metallic graphitic films, heterojunctions have been created on crystalline silicon. 6,7 However, charge accumulation at the interface or its leakage to the metal electrode without accumulation resulted due to the high defect density of states present in the films.…”

“…8 Hence, direct tunneling signatures in carbon MIS structures at low bias or strong charge inversion at high bias has not been reported. 5,[9][10][11][12][13][14][15] In practice, the well-known negative differential conductance in oxide based MIS tunnel diodes or transistors has been suppressed due to the contribution of a large density of interface trap states 16,17 and limits high frequency operation. We have recently demonstrated negative differential resistance in a-C quantum well structures.…”

Effect of gas pressure on current-voltage characteristics of amorphous carbon film/silicon heterojunction

“…͓DOI: 10.1063/1.2776017͔ Amorphous carbon ͑a-C͒ films have attracted considerable interest in the past few years due to their potential applications in the field emission, 1,2 microelectronic devices, 3,4 hard coating, 5,6 and gas sensors. The results show that the gas pressure has a large effect on the reverse bias I-V characteristics of the junctions.…”