Se chemical passivation and annealing treatment for GaAs Schottky diode

Abstract

A Se chemical passivation [(NH4)2S+Se] for GaAs Schottky diodes is presented. We have found that our (NH4)2S+Se passivated Schottky diodes have more than one order of magnitude higher forward current density than the (NH4)2Sx passivated ones. In rapid thermal annealing treatment, an initial decrease and then increase of forward current density for (NH4)2Sx passivated diodes is observed. For the (NH4)2S+Se and (NH4)OH treated diodes, a steady decrease of Schottky barrier height with increased annealing temperature is observed. With or without annealing treatment, the (NH4)2S+Se passivated diodes have the lowest barrier height.

Surface Chemistry of Prototypical Bulk II−VI and III−V Semiconductors and Implications for Chemical Sensing

“…Combined selenium and sulfur treatments have become popular, particularly use of SeS 2 , in an effort to exploit the beneficial effects of both kinds of atoms. ,− Kuruvilla et al identified a correlation between film thickness and PL efficiency, with the thinnest SeS 2 films producing the greatest PL intensities. − On the basis of AFM studies, they attribute this observation to the existence of a well-ordered (1 × 1) adlayer, with a lattice period of 3.8 Å on the GaAs (100) surface. This value is close to that of ∼4 Å for the unreconstructed surface, and the nearly matched lattice parameters may be related to energetic stabilization of the GaAs surface through surface structural modification.…”

Effects of swift heavy ion irradiation on the electrical characteristics of Au/n-GaAs Schottky diodes

“…Any mechanism that modifies the properties of the interface such as the introduction of an interfacial layer [1][2][3][4], annealing [5,6], irradiation with gamma rays [7,8], protons [9][10][11][12][13][14] and neutrons [14][15][16], ion implantation, [17][18][19] and high-energy ion beam irradiation [20][21][22][23][24][25][26] are found to alter the characteristics of the barrier. The Schottky barrier height (SBH) forms a very important parameter of the diode as it controls the electrical transport across the barrier.…”

The Influence of Annealing on Current-Voltage Characteristics of H2SeO3 Treated Al-nGaAs Schottky Contact

“…Chalcogenide passivation seems to be one of the most promising means to solve this problem. Presently, the most commonly used is wet chemical GaAs surface modification by sulfides (especially sodium (Na 2 S Á 9 H 2 O) or ammonium ((NH 4 ) 2 S, (NH 4 ) 2 S x ) sulfides [4,5,8,9,10,15]). GaAs surface chalcogenide treatment can be performed by using vacuum deposition techniques (physical deposition of monolayers of elemental chalkogenides, or treatment in H 2 Se or H 2 S [1, 2, 11, 19 to 22], or using wet chemical chalcogenide treatment methods [3, 4 to 10, 14 to 18].…”

“…Schottky barrier height control [1 to 11] and surface recombination rate reduction [3, 12 to 18] were obtained in this way. But more effective for GaAs surface passivation seems to be Se treatment, because of its possible higher thermal stability and resistivity against oxidation [7,8,9,17,22]. Presently, the most commonly used is wet chemical GaAs surface modification by sulfides (especially sodium (Na 2 S Á 9 H 2 O) or ammonium ((NH 4 ) 2 S, (NH 4 ) 2 S x ) sulfides [4,5,8,9,10,15]).…”

“…Despite numerous papers about the effect of sulphur or selenium passivation on the III±V characteristics of Al±GaAs Schottky contacts [1, 3, 5, 6, 8 to 10], there are only a few studies about the influence of annealing treatment on the electrical characteristics of Al±GaAs Schottky contacts, passivated by wet chemical selenium treatment. In some of these papers [8,9] a combination of selenium and sulphur (by (NH 4 ) 2 S + Se) treatment was used, and for similar Se treatment techniques different thermal stability was reported.…”