• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.12S
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• pp.1187-1194
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• 2003

A BCl$_3$/Ne plasma chemistry was used to etch Ga-based (GaAs, AIGaAs, GaSb) and In-based (InGaP, InP, InAs and InGaAsP) compound semiconductors in a Planar Inductively Coupled Plasma (ICP) reactor. The addition of the Ne instead of Ar can minimize electrical and optical damage during dry etching of III-V semiconductors due to its light mass compared to that of Ar All of the materials exhibited a maximum etch rate at BCl$_3$ to Ne ratios of 0.25-0.5. Under all conditions, the Ga-based materials etched at significantly higher rates than the In-based materials, due to relatively high volatilities of their trichloride etch products (boiling point CaCl$_3$ : 201 $^{\circ}C$, AsCl$_3$ : 130 $^{\circ}C$, PCl$_3$: 76 $^{\circ}C$) compared to InCl$_3$ (boiling point : 600 $^{\circ}C$). We obtained low root-mean-square(RMS) roughness of the etched sulfate of both AIGaAs and GaAs, which is quite comparable to the unetched control samples. Excellent etch anisotropy ( > 85$^{\circ}$) of the GaAs and AIGaAs in our PICP BCl$_3$/Ne etching relies on some degree of sidewall passivation by redeposition of etch products and photoresist from the mask. However, the surfaces of In-based materials are somewhat degraded during the BCl$_3$/Ne etching due to the low volatility of InCl$_{x}$./.

• Advances in nano research
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• v.2 no.4
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• pp.211-217
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• 2014

The self-assembled strain-induced sub-micrometric islands and nanostructures are grown from In-As-Sb-P quaternary liquid phase on InAs (100) substrates in Stranski-Krastanow growth mode. Two samples are under consideration. The first sample consists of unencapsulated islands and lens-shape quantum dots (QDs) grown from expressly inhomogeneous liquid phase. The second sample is an n-InAs/p-InAsSbP heterostructure with QDs embedded in the p-n junction interface. The morphology, size and shape of the structures are investigated by high-resolution scanning electron (SEM) and transmission electron (TEM) microscopy. It is shown that islands, as they decrease in size, undergo shape transitions. Particularly, as the volume decreases, the following succession of shape transitions are detected: sub-micrometric truncated pyramid, {111} facetted pyramid, {111} and partially {105} facetted pyramid, completely unfacetted "pre-pyramid", hemisphere, lens-shaped QD, which then evolves again to nano-pyramid. A critical size of $5{\pm}2nm$ for the shape transformation of InAsSbP-based lens-shaped QD to nano-pyramid is experimentally measured and theoretically evaluated.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.2
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• pp.2-11
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• 2000

Technologies for high-speed transistors, active devices essential to the fabrication of millimeter wave circuits have developed drastically with the design and processing techniques. The high frequency transistors, made of GaAs or InP related compound semiconductors mainly, are in the form of MODFETs and HBTs. Other than traditional III-V compound semiconductor materials, SiGe and GaN technologies are emerging as viable candidates of millimeter-wave devices. In this paper, basis and applications of millimeter-wave transistors are introduced.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.973-976
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• 2004

The results of numerous studies in III-V semiconductors show that sulfur treatment improves the electrical parameters of III-V compound devices. In this article, we examine the effects of sulfidation of HgCdTe surface on the interfacial characteristics of metal-ZnS-HgCdTe structures. Different from sulfidation in III-V material, S can not be act as an impurity because II-S compounds (ZnS, CdS) generally used as passivant for HgCdTe. Our studies of sulfur-treatment on HgCdTe surface show that sulfur agent forms the S- S, II-S bonds at the surface layer. These bonds are very effective to improve the electrical properties of ZnS layer on HgCdTe by reducing the possibility of native oxides formation. After the sulfidation process, MIS capacitors of HgCdTe show great improvement in electrical properties, such as low density of fixed charge and reduced hystereisis width.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.533-534
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• 2012

Colloidal III-V semiconductor nanocrystal quantum dots (NQDs) have attracted attention as they can be applied in various areas such as LED, solar cell, biological imaging, and so on because they have decreased ionic lattices, lager exciton diameter, and reduced toxicity compared with II-VI compounds. However, the study and application of III-V semiconductor nanocrystals is limited by difficulties in control nucleation because the molecular bonds in III-V semiconductors are highly covalent compared to II-VI compounds. There is a need for a method that provides rapid and scalable production of highly quality nanoparticles. We present a new synthetic scheme for the preparation of InP nanocrystal quantum dots using new phosphorus precursor, P(SiMe2tbu)3. InP nanocrystals from 530nm to 600nm have been synthesized via the reaction of In(Ac)3 and new phosphorus precursor in noncoordinating solvent, ODE. This opens the way for the large-scale production of high quality Cd-free nanocrystal quantum dots.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.353-355
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• 1988

The properites of Zn-diffusion in III-V ternary alloy semiconductor $In_{1-x}Ga_{x}p$, which was grown by the temperature gradient solution (TGS) method, have been investigated. The composition, x, dependence of the Zn-diffusion coefficient at $850^{\circ}C$ and the activation energy for Zn-diffusion into $In_{1-x}Ga_{x}p$ were found to be $D850^{\circ}C$(x)= $3.935{\times}10^{-8}exp(-6.84{\cdot}x)$, and $E_{A}(x)=1,28+2,38{\cdot}x$, respectively. From this study, we confirm that the Zn-diffusion in $In_{1-x}Ga_{x}p$ was explainable with the diffusion mechanisms of the interstitial-substitutional, which was widely accepted mechanisms in the III-V binary semiconductors.

• Electronics and Telecommunications Trends
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• v.33 no.6
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• pp.34-40
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• 2018

Traditionally, many researchers have conducted research on terahertz technology utilizing optical devices such as lasers. However, nanometer-scale electronic devices using silicon or III-V compound semiconductors have received significant attention regarding the development of a terahertz system owing to the rapid scaling down of devices. This enables an operating frequency of up to approximately 0.5 THz for silicon, and approximately 1 THz for III-V devices. This article reviews the recent trends of terahertz monolithic integrated circuits based on several electronic devices such as CMOS, SiGe BiCMOS, and InP HBT/HEMT, and a particular quantum device, an RTD.

• Proceedings of the Korean Magnestics Society Conference
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• 2002.12a
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• pp.146-147
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• 2002

III-V magnetic semiconductors initiated by GaMnAs growth at low temperatures via molecular beam epitaxy (MBE) has been a hot issue recently for their possible application to spntronics. GaMnN may be one of the candidates for room temperature operating ferromagnetic semiconductors as proposed by a theoretical calculation, However, since GaN was grown at very high temperatures above ∼750$^{\circ}C$ even with MBE, it is expected that the incorporation of Mn into GaN will be limited. (omitted)

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.268.2-268.2
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• 2007

• Transactions on Electrical and Electronic Materials
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• v.10 no.4
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• pp.107-110
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• 2009

In this study, the Hall effect has been studied in n-GaAs samples characterized by V/IIl growth ratios of 25, 50 and 100 and prepared by metal organic chemical vapor deposition. For the Hall effect measurements, the grown samples were cut to a size of 1${\times}$1 cm. The measurements were carried out at room temperature, using Indium contact metal at the four corners of the samples. According to the experimental results, the Schottky effect was not ovservation. Also for the n-GaAs sample of V/Ill 100 ratio the electron drift velocity was very high.