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J. Majhi

Bio: J. Majhi is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Silicon & X-ray photoelectron spectroscopy. The author has an hindex of 2, co-authored 4 publications receiving 16 citations.

Papers
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Journal ArticleDOI
TL;DR: Using X-ray photoelectron spectroscopy, the chemical state of a silicon surface treated with hydrofluoric acid and the resulting contaminant species (fluorine, carbon and oxygen) were studied as a function of the etchant concentration.

12 citations

Journal ArticleDOI
TL;DR: In this article, the authors used variable illumination current-voltage measurements on semi-transparent metal gate metal-insulator-semiconductor diodes to study the open-circuit voltage, shortcircuit current, ideality factor and reverse saturation current.

3 citations

Journal ArticleDOI
TL;DR: In this article, the flat-band voltages were estimated as a function of the a-Si:H film thickness and the density of states around the midgap NF was also estimated following the theory put forward by Harm et al.

1 citations

Journal ArticleDOI
TL;DR: In this article, the I-V and C-V characteristics of MIS diodes fabricated on silicon surfaces treated with 5% HF were investigated and it was observed that the ideality factor n = 1.25, density of interface states Dit = 9 × 1011/ cm-2 eV-1, effective barrier height Vb = 0.74 V, open-circuit voltage Voc =0.28 V, and density of fixed oxide charges Q 0~1011 cm 2 of 5%HF treated dioded are lower than those of untreated devices
Abstract: Our earlier XPS and UPS studies have shown that etching a silicon surface with 5% HF concentration produces a stable surface with minimum contamination and low density of surface states. This has prompted us to study the I-V and C-V characteristics of MIS diodes fabricated on silicon surfaces treated with 5% HF. Tunnel oxides of ~20 A are grown on p-type (100) surfaces by a high-pressure (2 atm) and low-temperature (250 °C) method. Aluminum dots are vacuum evaporated through metal masks onto the oxide to fabricate MIS diodes. For photovoltaic measurements the gate electrode is made semitransparent by reducing its thickness to ~120 A. From the variable-illumination current-voltage characteristics it is observed that the ideality factor n = 1.25, density of interface states Dit = 9 × 1011/ cm-2 eV-1, effective barrier height Vb = 0.74 V, open-circuit voltage Voc = 0.28 V and density of fixed oxide charges Q0~1011 cm-2 of 5% HF treated diodes are lower than those of untreated devices where n = 1.54, Dit = 2 × 1012 cm-2 eV-1, Vb = 0.78 V, Voc = 0.42 V and Q0~1012 cm-2. This is attributed to the removal of the native oxide and passivation of silicon dangling bonds by HF treatment. C-V characteristics of the MIS diodes also confirmed the reduction in barrier height on HF treatment. An increase in negative charges with increasing HF concentration, possibly due to excess of fluorine ions which may be responsible for the reduction in barrier height, is found in the interfacial layer.

Cited by
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Journal ArticleDOI
TL;DR: In this paper, the surface films formed under these dynamic heat-transfer conditions are characterized with the use of X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) is also used for the study and characterization of the surface film formed.
Abstract: Carboxylic acids are found to adsorb weakly to the native oxide surface of aluminum. Under heat exchange conditions, synergistic carboxylate combinations provide superior high-temperature aluminum corrosion protection and show excellent heat-transfer characteristics. The surface films formed under these dynamic heat-transfer conditions are characterized with the use of X-ray photoelectron spectroscopy (XPS). Fourier transform infrared (FT-IR) is also used for the study and characterization of the surface films formed. The results are compared with the FT-IR data of the pure Al-carboxylate complexes. The combination of these results reveals that, under heat transfer conditions, carboxylates are chemically bonded to the aluminum surface. This molecular film shows excellent inhibition properties for aluminum.

46 citations

Patent
11 Sep 1984
TL;DR: In this article, a catalyst comprising an inorganic refractory oxide support containing at least one of tungsten oxide and molybdenum oxide and a promoting amount of at least a methylating agent under conditions suitable for the methylating agents to promote the activity of the oxides for the disproportionation reaction.
Abstract: Olefins are converted into other olefins having different numbers of carbon atoms by contact with a catalyst comprising an inorganic refractory oxide support containing at least one of tungsten oxide and molybdenum oxide and a promoting amount of at least one methylating agent under conditions suitable for the methylating agent compounds to promote the activity of tungsten and molybdenum oxides for the disproportionation reaction.

26 citations

Journal ArticleDOI
TL;DR: In this paper, a combination of conventional, angle-resolved and depth profiling X-ray photoelectron spectroscopy (XPS) was used to characterize the Niobic acid monolayer.

21 citations

Journal ArticleDOI
TL;DR: Using X-ray photoelectron spectroscopy, the chemical state of a silicon surface treated with hydrofluoric acid and the resulting contaminant species (fluorine, carbon and oxygen) were studied as a function of the etchant concentration.

12 citations

Journal ArticleDOI
TL;DR: In this paper, a model support consisting of a thin layer of SiO2 on a Silicon single crystal has been used to study the [W]n+/SiO2/Si (100) model catalyst precursor prepared by a controlled reaction of π-C5H5W(CO)3Cl with the SiO 2 surface.

11 citations