Corrosion of III–V compounds; a comparative study of GaAs and InP: II. Reaction scheme and influence of surface properties

The paper presents a detailed reaction model for the corrosion of III–V compounds which quantitatively represents the experimental data (mainly Tafel plots of current vs. band displacement), presented in Part I J. Electroanal. Chem. Such data allow the discrimination between different reaction schemes. From a physical point of view, the model shows clearly that the differences observed between GaAs and InP arise from their different electronic surface properties. From a chemical point of view, a chemical signature of the corrosion states of GaAs is proposed: the states EC −0.98 eV and EC −1.15 eV, previously derived from photocapacitance spectroscopy, Ber. Bunsenges. Phys. Chem. 92 (1988) 895, could be associated with As sites and Ga sites, respectively. An analogous description holds for InP, with different positions of states. Within the framework of these original data, corrosion can be described by a first hole capture process on the cation site which becomes an anion site by the liberation of the cation. A chemical reaction step occurs before the second hole capture proceeds to dissolve the anion-related defect. Such a description is predicted by thermodynamical data and is further sustained by experimental facts such as the well-known As enrichment of GaAs surface in acidic media

Corrosion of III-V compounds; a comparative study of GaAs and InP: Part I. Electrochemical characterization based on Tafel plot measurements

The kinetics and mechanism of corrosion of GaAs and InP have been investigated quantitatively by means of a combined experimental approach based principally on (i) Tafel plot measurements and (ii) the comparison of n- and p-type electrodes of the same material. In this work (Part I), the motivations and the limit of validity of this approach are discussed in detail along with the description of experimental results. It is shown that an extensive determination of the flat band potential under various electrochemical conditions (called in the following “Tafel plot recording” by analogy with metal substrates) is a very powerful technique, sensitive to a number of parameters of the contact such as (i) the pH of the solution, (ii) the doping density of the electrode, (iii) the type of electrode conduction (n-or p-type) and naturally (iv) the material itself. The present work brings new insight into electrochemical studies of the semiconductor/electrolyte junction and makes a parallel with the electrochemistry with metal electrodes. This part presents only the results. Part II will cover the discussion in relation to the surface electrochemical and chemical properties of GaAs and InP

Resistive switching study in HfO 2 based resistive memories by conductive atomic force microscopy in vacuum

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Pre-Breakdown Negative Differential Resistance in thin oxide film: Conductive-Atomic Force Microscopy observation and modelling

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Sign of the nonlinear dielectric susceptibility of amorphous and crystalline SrTiO 3 films

International audienc

Characterization of High-k Bilayer Gate Stack Breakdown Mechanisms at Nanometric Scale

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A nanoscale study of hafnium oxide resistive memory switching dynamics

International audienceAbstract This paper deals with the set and reset time measurements of a resistive memory consisting of a Ti/TiN/HfO 2 layer stack contacted with the tip of a conductive atomic force microscope in ultra high vacuum. We present measurements of the set and reset switching times in voltage pulse regime for different voltages and compliance currents. The experimental results are well reproduced by simulation. We derive analytical expressions for the set and reset times as function of experimental conditions. The effect of voltage and current on reset and set switching times is then discussed with the help of their analytical expressions, which are also applied on standard devices characteristics

Caractérisation des propriétés électriques a l'échelle nanométrique de diélectriques en couche mince par C-AFM sous UHV

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Nanoscale Characterization of High-K/IL Gate Stack TDDB Distributions After High-Field Prestress Pulses

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