| When the scale of semiconductor material was reduced to the nanometer range (1～100nm) at least one dimension, four nanoparticles-induced effects will be brought about- surface effect, quantum size effect, small size effect and macroscopic quantum tunneling effect. A variety of potential nano-device applications can be derivative from these new effects. One of the main tasks in early 21 century is to innovate the new generation of quantum electronic devices, which can satisfy to the 21 st century high-density information processing technology. Research and development of nano-devices have become a new research focus and an economic growth point of future new economic era.First, this thesis describes the preparation of Ag/SiNWs Schottky Barrier Diodes (Ag/SiNWs SBDs). Using a galvanic displacement method (ie, chemical etching), we had fabricated the vertically-aligned Silicon nanowires arrays. Silver particals are modified onto the surface of silicon nanowires via Electroless plating and used as the Schottky Contact. The Ohmic contact was formed by thermal evaporation Al on the other side of silicon and followed by and rapid thermal annealing (RTA). The morphology and crystal structure of the Ag/SiNWs were analyzed with SEM and X-ray diffraction.Secondly, the current-voltage-temperature properties (I-V-T) of Ag/SiNWs SBDs were studied. It is demonstrated that Ag and SiNWs formed a Schottky contact, with a clear rectifying behavior and the forward turning-on voltage～1 V. Comparing theⅠ-Ⅴcharacteristics of n- and p-type silicon substrate Ag/SiNWs Schottky diodes, we found that Ag/n-SiNWs SBDs had the better rectifying properties and the reverse cut-off characteristics. And the reverse breakdown voltage of Ag/n-SiNWs is more than 10V at least. The reverse current increases with temperature increasing with certain regularity. Relative to Ag/n-SiNWs SBD, the reverse breakdown voltage Ag/p-SiNWs SBD is lower. The change regularity of Ag/p-SiNWs SBD positive and negativeⅠ-Ⅴcharacteristics with temperature is not obvious.Finally, Ag/n-SiNWs SBDs had been chosen to study well the device characteristics and analyse the current transport mechanism and the temperature- sensitive properties in detail.1. Under room temperature (T=300K), the parameters of Ag/n-SiNWs SBDs had been extracted following Cheung's model and the barrier height, the series resistance, and the ideality factor obtained are 0.957eV,1157.6Ω,3.9, respectively. The forward current transport mechanism is not dominated by the ideal thermionic emission.2. Current transport mechanism of Ag/n-SiNWs SBD is analysed by 1stOpt Software which can fit the experimentalⅠ-Ⅴcurve with the theretical models. The modeling indicated that the current transport mechanisms are affected by a combination of thermionic emission, tunneling, generation- recombination and leakage current, in which thermionic electron emission mechanism play a leading role.3. The slope of ideality factor, n, versus T curve for Ag/n-SiNWs SBD is twice bigger than that of Ag/n-Si one. We can derive that Ag/n-SiNWs SBD prepared on SiNWs substrate has higher temperature-sensitive properties than Ag/n-Si SBD based on bulk silicon substrate.4. Under reverse bias, current through the Ag/SiNWs SBD increases with temperature increasing. Cuvre In|Js| vs.-1000/T is linear. When the reverse bias voltage is about 2.1V, the slope of the cuvre reaches a maximum 5.433. |
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