Experimental investigation and simulation of hybrid organic/inorganic Schottky diodes

Abstract

We have investigated electronic transport in hybrid organic/inorganic Schottky diodes. In order to derive from basic principles the transport properties of the organic semiconductors, we have use a two-dimensional drift-diffusion simulator which properly accounts for transport in both organic and inorganic layers. We have calculated the I-V characteristics of Ag/PTCDA/GaAs Schottky diodes as a function of PTCDA thickness and compared the results with experimental in situ measurements. The interplay between barrier height, PTCDA thickness, space-charge-limited current, and image charge is outlined.

Laterally inhomogeneous barrier analysis of the methyl violet/p-Si organic/inorganic hybrid Schottky structures

“…The case may be ascribed to an organic interlayer modifying the effective barrier height by influencing the space charge region of the inorganic substrate [23,54]. Thereby, it is known that the organic film forms a physical barrier between the metal and the Si substrate, preventing the metal from directly contacting the Si surface [17,18,[21][22][23][24][25][26]54]. The methyl violet organic layer appears to cause a significant modification of interface states even though the organic/inorganic interface becomes abrupt and unreactive [17,18,[21][22][23][24][25][26]54].…”

“…Namely, many devices using the polymeric [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] and nonpolymeric organic materials [17][18][19][20][21][22][23][24][25][26][27][28][29] have been fabricated including light emitting diodes and Schottky (Metal/Semiconductor = MS) type devices like an inorganic semiconductor/ organic semiconductor material or a metal/organic semiconductor material, and their electrical and photoelectrical properties have been investigated for more than three decades.…”

“…By means of the choice of the organic molecule and the interlayer thickness, the device can be designed to exhibit the desired properties. Thereby, the inclusion of thin films of organic semiconductors with nanometer thickness in inorganic Schottky diodes introduces a method to control the fundamental device parameters [13,[23][24][25][26]. Methyl violet with molecular formula C 25 H 30 ClN 3 used in this work is a typical aromatic azo compound.…”

Electronic parameters of MIS Schottky diodes with DNA biopolymer interlayer

“…The DNA organic interlayer appears to cause a significant modification of interface states even though the organic-inorganic interface becomes abrupt and unreactive [14,47]. Thus, the change in barrier height can qualitatively be explained by an interface dipole induced by the organic layer passivation [12,15]. Kampen et al [12] have observed by photoemission spectroscopy investigations that the sulphur passivation reduces the surface band bending on n-type doped GaAs, whereas the band bending on the surfaces of p-type doped GaAs increases.…”

“…For example, many devices using polymeric [1][2][3][4][5][6][7] and nonpolymeric organic materials [8][9][10][11][12][13][14][15], including light emitting diodes and devices, such as an inorganic/organic and a metal/organic heterostructures, have been fabricated. Attractive features of these materials offer the possibility for device processing, compatibility with flexible substrates, and low materials consumption for ultra thin molecular films, all of which give the prospect of cheaper photovoltaic energy generation [16].…”