Forming ohmic Ag/SnO2 contacts

Electrical characteristics of interfacial barriers at metal—TiO2 contacts

“…Considering the up todate studies, metal contacts on oxide materials appear to be attracting important and continuously increasing research attention. Various metals on various oxide materials have been assessed, and focused methods have been introduced aiming at both the development of reliable contacts [27] and an understanding of the formation mechanism [28,29]. Moreover, important advances in understanding the nature of metal/oxide (electrolyte) contacts are also being made in the field of RRAM cells, revealing the interesting nanobattery effect [30] and highlighting the role redox processes [31] of interfacial layers [32] and moisture [33].…”

A Study of Visible-Blind Properties of a SnO2’s Nanowires Network Photodetector

“…In other words, the electrical response we observe is the randomly percolation pathway chosen by the current to flow from one The devices were manufactured in an MSM structure [10], in which Ag paste was used for the electrical contacts. The fabrication process with Ag paste was chosen due to its high quality mechanical adhesion, not only to the nanowires, because it can penetrate into the nanowire network, inset in Figure 3a, but also to the external electrical circuit, simplifying the assembly of an integrated circuit [18,19]. Before starting a discussion about the visible-blind photodetector and photoconductivity effect in SnO 2 nanowire networks, some details should be discussed.…”

Diffusion Bonding of Metal Wires Directly to the Functional Metal Oxide Semiconductors for Forming Reliable Electrical Contacts

“…The metallic contact is then stabilized by thermal annealing. Metal wires connecting the device to the external circuitry are subsequently bonded to these metallic electrodes. − The complexity of this multistep process is detrimental to the reproducibility of the fabrication and the effective life span of the fabricated devices and increases the overall cost. In the devices operating at elevated temperatures, particularly, the gradual field-assisted migration of the metal electrodes into the functioning oxide and the substrate ,, necessitates the deposition of costly micron-thick noble metal electrodes.…”

“…The quality of the produced metal/metal oxide electric contacts are tested by forming a counter contact on the oxide layer with a much larger effective contact area. The I – V characteristics of such an asymmetric metal/metal oxide/metal structure would depict the quality of the smaller (test) contact. , The counter electrode is a vacuum deposited Au thin film circularly surrounding the test electrode which is formed through the diffusion bonding of a metal wire to the oxide layer (see Figure a). The I – V characteristics of an Au/SnO 2 /Au sample in the temperature range of 35–500 °C are shown in Figure b.…”

“…The method is successful in producing gold, platinum, silver, copper, and aluminum contacts to SnO 2 , ZnO, and TiO 2 films. The ohmicity of the produced contacts, however, would depend on the natures of the involved metal oxide and metal. , Generally, the optimum bonding temperature is lower for the oxide layers of finer grain structure. This is, particularly, clear in the results obtained for the SnO 2 layers of different nanostructures produced by USP depositions carried out at different substrate temperatures.…”