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Article
Publication date: 1 November 1944

William S. Murray

IT is particularly appropriate to discuss Indium at a meeting of the Institute of the Aeronautical Sciences for it is in the aviation industry that Indium has received its…

Abstract

IT is particularly appropriate to discuss Indium at a meeting of the Institute of the Aeronautical Sciences for it is in the aviation industry that Indium has received its greatest acclaim and has contributed so materially to the perfection of vital war machines. Indium in aviation is a reality and has long since passed the experimental stage and has become a vital factor in both power plants and airscrews.

Details

Aircraft Engineering and Aerospace Technology, vol. 16 no. 11
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 February 1991

M. Plötner, G. Sadowski, S. Rzepka and G. Blasek

Indium solders are frequently used for interconnections in cooled systems because of their high ductility down to very low temperatures. Very fine contact pitches are required for…

Abstract

Indium solders are frequently used for interconnections in cooled systems because of their high ductility down to very low temperatures. Very fine contact pitches are required for hybrid mosaic radiation sensors compared with those for conventional flip‐chip technology. This paper presents solutions for bumping and bonding indium bumps based on the measured properties of indium solders in relation to the requirements of, and possibilities for, manufacture of fine pitch solder bump features.

Details

Microelectronics International, vol. 8 no. 2
Type: Research Article
ISSN: 1356-5362

Article
Publication date: 10 June 2022

Nur Atiqah Hamzah, Mohd Ann Amirul Zulffiqal Md Sahar, Aik Kwan Tan, Mohd Anas Ahmad, Muhammad Fadhirul Izwan Abdul Malik, Chin Chyi Loo, Wei Sea Chang and Sha Shiong Ng

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN…

Abstract

Purpose

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN) heterostructures.

Design/methodology/approach

The InGaN/GaN heterostructures were grown on flat sapphire substrates using a metal-organic chemical vapour deposition reactor with a trimethylindium flow rate of 368  sccm. The indium composition of the InGaN epilayers was controlled by applying different substrate temperatures. The surface morphology and topography were observed using field emission scanning electron microscope (F.E.I. Nova NanoSEM 450) and atomic force microscopy (Bruker Dimension Edge) with a scanning area of 10 µm × 10 µm, respectively. The compositional analysis was done by Energy Dispersive X-Ray Analysis. Finally, the ultraviolet-visible (UV-Vis) spectrophotometer (Agilent Technology Cary Series UV-Vis-near-infrared spectrometer) was measured from 200 nm to 1500 nm to investigate the optical properties of the samples.

Findings

The InGaN/GaN thin films have been successfully grown at three different substrate temperatures. The indium composition reduced as the temperature increased. At 760 C, the highest indium composition was obtained, 21.17%. This result was acquired from the simulation fitting of ω−2θ scan on (0002) plane using LEPTOS software by Bruker D8 Discover. The InGaN/GaN shows significantly different surface morphologies and topographies as the indium composition increases. The thickness of InGaN epilayers of the structure was ∼300 nm estimated from the field emission scanning electron microscopy. The energy bandgap of the InGaN was 2.54 eV – 2.79 eV measured by UV-Vis measurements.

Originality/value

It can be seen from this work that changes in substrate temperature can affect the indium composition. From all the results obtained, this work can be helpful towards efficiency improvement in solar cell applications.

Details

Microelectronics International, vol. 40 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 August 1970

R.W. Wilson and E.B. Shone

AN OVERLAY bearing is a bearing with a precision electroplated overlay of lead‐tin or lead‐indium alloy, 20 to 40µ thick. This lead‐alloy overlay is generally applied to a…

Abstract

AN OVERLAY bearing is a bearing with a precision electroplated overlay of lead‐tin or lead‐indium alloy, 20 to 40µ thick. This lead‐alloy overlay is generally applied to a copper‐lead or lead‐bronze substrate, which is itself bonded to a steel backing. Bearings of this construction are probably the most extensively used type of engine bearings; many millions are manufactured annually. The main functions of the overlay are to provide a seizure‐resistant surface, to increase the tolerance of the bearing for dirt and wear‐debris, and to protect the lead in the underlying copper‐lead or lead‐bronze alloy from corrosion by oxidized oil. When mineral oils are exposed to air oxidation for prolonged periods at elevated temperatures, weak organic acids are formed which can dissolve pure lead. The lead in copper‐lead or lead‐bronze is present as a separate, unalloyed phase, very susceptible to corrosion by weak organic acids. However, it has been known for some time that if lead is alloyed with indium or tin it is not corroded in this way. Most bearing manufacturers incorporate at least 4%w indium or 8%w tin in overlays to make them resistant to corrosion, but precise information on the amounts of alloying element required is not available.

Details

Anti-Corrosion Methods and Materials, vol. 17 no. 8
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 7 January 2022

Madhuri Chandrashekhar Deshpande, Rajesh Chaudhari, Ramesh Narayanan and Harishwar Kale

This study aims to develop indium-based solders for cryogenic applications.

Abstract

Purpose

This study aims to develop indium-based solders for cryogenic applications.

Design/methodology/approach

This paper aims to investigate mechanical properties of indium-based solder formulations at room temperature (RT, 27 °C) as well as at cryogenic temperature (CT, −196 °C) and subsequently to find out their suitability for cryogenic applications. After developing these alloys, mechanical properties such as tensile and impact strength were measured as per American Society for Testing and Materials standards at RT and at CT. Charpy impact test results were used to find out ductile to brittle transition temperature (DBTT). These properties were also evaluated after thermal cycling (TC) to find out effect of thermal stress. Scanning electron microscope analysis was performed to understand fracture mechanism. Results indicate that amongst the solder alloys that have been studied in this work, In-34Bi solder alloy has the best all-round mechanical properties at RT, CT and after TC.

Findings

It can be concluded from the results of this work that In-34Bi solder alloy has best all-round mechanical properties at RT, CT and after TC and therefore is the most appropriate solder alloy amongst the alloys that have been studied in this work for cryogenic applications

Originality/value

DBTT of indium-based solder alloys has not been found out in the work done so far in this category. DBTT is necessary to decide safe working temperature range of the alloy. Also the effect of TC, which is one of the major reasons of failure, was not studied so far. These parameters are studied in this work.

Details

Soldering & Surface Mount Technology, vol. 34 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 19 July 2021

Mohd Ann Amirul Zulffiqal Md Sahar, Zainuriah Hassan, Sha Shiong Ng, Way Foong Lim, Khai Shenn Lau, Ezzah Azimah Alias, Mohd Anas Ahmad, Nur Atiqah Hamzah and Rahil Izzati Mohd Asri

The aims of this paper is to study the effects of the V/III ratio of indium gallium nitride (InGaN) quantum wells (QWs) on the structural, optical and electrical properties of…

Abstract

Purpose

The aims of this paper is to study the effects of the V/III ratio of indium gallium nitride (InGaN) quantum wells (QWs) on the structural, optical and electrical properties of near-ultraviolet light-emitting diode (NUV-LED).

Design/methodology/approach

InGaN-based NUV-LED is successfully grown on the c-plane patterned sapphire substrate at atmospheric pressure using metal organic chemical vapor deposition.

Findings

The indium composition and thickness of InGaN QWs increased as the V/III ratio increased from 20871 to 11824, according to high-resolution X-ray diffraction. The V/III ratio was also found to have an important effect on the surface morphology of the InGaN QWs and thus the surface morphology of the subsequent layers. Apart from that, the electroluminescence measurement revealed that the V/III ratio had a major impact on the light output power (LOP) and the emission peak wavelength of the NUV-LED. The LOP increased by up to 53% at 100 mA, and the emission peak wavelength of the NUV-LED changed to a longer wavelength as the V/III ratio decreased from 20871 to 11824.

Originality/value

This study discovered a relation between the V/III ratio and the properties of QWs, which resulted in the LOP enhancement of the NUV-LED. High TMIn flow rates, which produced a low V/III ratio, contribute to the increased LOP of NUV-LED.

Details

Microelectronics International, vol. 38 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 October 2001

J. Mathiyarasu, L.C. Nehru, P. Subramanian, N. Palaniswamy and N.S. Rengaswamy

Aluminium alloys are being employed very widely as galvanic anodes for cathodic protection. Aluminium‐zinc‐mercury and aluminium‐zinc‐indium are the popular alloys that are used…

Abstract

Aluminium alloys are being employed very widely as galvanic anodes for cathodic protection. Aluminium‐zinc‐mercury and aluminium‐zinc‐indium are the popular alloys that are used as anodes. In general, the alloying ingredients activate aluminium and maintain uniform dissolution. In the present investigation, the role of addition of gallium in the ternary alloy of aluminium‐zinc‐indium has been studied by making use of polarisation studies, capacity measurements and galvanic current measurements.

Details

Anti-Corrosion Methods and Materials, vol. 48 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 June 1990

I.D. Massey, N.A. MacQuarrie and D.R. Eastham

Modern highly loaded engines, particularly long life diesel engines, require main and connecting‐rod bearings that combine fatigue and wear resistance with an ability to absorb…

Abstract

Modern highly loaded engines, particularly long life diesel engines, require main and connecting‐rod bearings that combine fatigue and wear resistance with an ability to absorb dirt and cater for slight misalignment. With the extended oil drain intervals, corrosion resistance is also ever important.

Details

Industrial Lubrication and Tribology, vol. 42 no. 6
Type: Research Article
ISSN: 0036-8792

Article
Publication date: 8 July 2021

Ahmad Sauffi Yusof, Zainuriah Hassan, Sidi Ould Saad Hamady, Sha Shiong Ng, Mohd Anas Ahmad, Way Foong Lim, Muhd Azi Che Seliman, Christyves Chevallier and Nicolas Fressengeas

The purpose of this paper is to investigate the effect of growth temperature on the evolution of indium incorporation and the growth process of InGaN/GaN heterostructures.

Abstract

Purpose

The purpose of this paper is to investigate the effect of growth temperature on the evolution of indium incorporation and the growth process of InGaN/GaN heterostructures.

Design/methodology/approach

To examine this effect, the InGaN/GaN heterostructures were grown using Taiyo Nippon Sanso Corporation metal-organic chemical vapor deposition (MOCVD) SR4000-HT system. The InGaN/GaN heterostructures were epitaxially grown on 3.4 µm undoped-GaN (ud-GaN) and GaN nucleation layer, respectively, over a commercial 2” c-plane flat sapphire substrate. The InGaN layers were grown at different temperature settings ranging from 860°C to 820°C in a step of 20°C. The details of structural, surface morphology and optical properties were investigated using X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), atomic force microscopy and ultraviolet-visible (UV-Vis) spectrophotometer, respectively.

Findings

InGaN/GaN heterostructure with indium composition up to 10.9% has been successfully grown using the MOCVD technique without any phase separation detected within the sensitivity of the instrument. Indium compositions were estimated through simulation fitting of the XRD curve and calculation of Vegard’s law from UV-Vis measurement. The thickness of the structures was determined using the Swanepoel method and the FE-SEM cross-section image.

Originality/value

This paper report on the effect of MOCVD growth temperature on the growth process of InGaN/GaN heterostructure, which is of interest in solid-state lighting technology, especially in light-emitting diodes and solar cell application.

Details

Microelectronics International, vol. 38 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 13 September 2013

Si Chen

The transferred carbon nanofibers (CNFs) can be applied in flip chip package as interconnect material, as an alternative to the conventional solder and conductive adhesive (CA…

Abstract

Purpose

The transferred carbon nanofibers (CNFs) can be applied in flip chip package as interconnect material, as an alternative to the conventional solder and conductive adhesive (CA) materials.

Design/methodology/approach

The structure of CNFs was confirmed by transmission electron microscopy (TEM). The electrical performance of the vertically aligned carbon nanofibers (VACNFs) joint was measured by four points probe method and compared to conventional lead‐free solder Sn3.0Ag0.5Cu, pure indium and silver CA. A shear test was carried out in order to evaluate the mechanical performance of VACNFs joint. After the shear test, the fracture surface was analyzed by scanning electron microscopy and energy dispersive spectroscopy (SEM‐EDS).

Findings

The results showed a high success rate in the transfer of VACNFs from growth chip to target chip. The Au‐coated CNF can be wetted well with melted indium during the transfer and bonding process. In‐Au intermetallic compound (IMC) formed on the surface of CNF. The electrical and mechanical performance of VACNFs is comparable to that of the traditional interconnect materials. The fracture surface is located at the interface between VACNFs and chips. The stacked‐cone structure of CNF can be confirmed from a cross‐section of the break CNF by TEM.

Originality/value

Ultra‐short VACNFs were grown and first successfully transferred to the target chip using a process which required little pressure, low temperature and short time.

Details

Soldering & Surface Mount Technology, vol. 25 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

1 – 10 of 623