Key role of nanocrystalline feature in porous polycrystalline silicon diodes for efficient ballistic electron emission

Abstract

Annealing effects on the operation stability of ballistic electron emission from electrochemically oxidized nanocrystalline silicon diodes Efficient and ballistic cold electron emission from porous polycrystalline silicon diodes with a porosity multilayer structure J.The cold electron emission characteristics of nanocrystalline porous polysilicon ͑PPS͒ diodes have been investigated for two PPS diodes prepared under different conditions. The origin of the difference in the emission efficiency and electron energy distribution between the two samples is analyzed in relation to the respective photoluminescence properties. The photoluminescence spectrum in the efficient electron emitter consists of red and blue emission bands corresponding to nanocrystalline silicon and interfacial oxide, respectively, while that in the low-efficiency emitter consists only of a blue band. Too much oxidation results in a reduction of the emission efficiency due to increased electron scattering. It is evident that both the formation of nanocrystalline silicon and its appropriate surface oxidation are key issues for obtaining efficient ballistic emission. These results are consistent with the emission model that electrons are accelerated in the PPS layer by multiple tunneling through interfacial oxide barriers between interconnected silicon nanocrystallites.

Photoluminescence, Composition and Microstructure of Porous Silicon Prepared by Different Substrates

“…In Ref. 24, the porous poly-crystalline silicon can emit strong visible light in the full visible light region. When the etched current density increased, the poly nano-crystalline silicon and amorphous crystalline silicon also increased in same time.…”

Annealing effects on the operation stability of ballistic electron emission from electrochemically oxidized nanocrystalline silicon diodes

“…4 The most important issue for fabrication of an efficient BSD is the arrangement of nc-Si chains interconnected via thin oxide films. Based on our previous studies on photoluminescence of partially oxidized nanocrystalline porous silicon, 5 we have suggested that there should be a definite correlation between the electron emission characteristics and the interfacial properties of interconnected nc-Si dots. 6,7 It is important to reduce these interfacial defects for promoting ballistic transport.…”

Direct excitation of xenon by ballistic electrons emitted from nanocrystalline‐silicon planar cathode and vacuum‐ultraviolet light emission

“…Energetic electrons are generated via multiple-tunnel transport through a chain of nc-Si dots interconnected with thin oxide films. [1][2][3][4] The mean energy of emitted electrons is strongly affected by the nanostructure in the device where chainlike nc-Si structures are produced along columnar poly-Si grains. In the well-controlled device, the current-voltage (I-V) curves behave in the way expected from the tunneling mode with little scattering energy losses.…”