Journal of Vacuum Science

Electrical properties of C60 and Si codoped GaAs layers

Tue, 24 Jan 2012 00:00:00 EST

Jiro Nishinaga and Yoshiji Horikoshi
C60 uniformly doped GaAs and C60, Si codoped GaAs layers are grown by a migration enhanced epitaxy method. C60 doped GaAs layers show a single and sharp diffraction peak in x-ray diffraction and only an LO phonon peak is confirmed, indicating that the crystalline quality is fairly good. All of the ... [J. Vac. Sci. Technol. B 30, 02B116 (2012)] published Tue Jan 24, 2012.

Magnetic anisotropy of GaAs/Fe/Au core-shell nanowires grown by MBE

Tue, 24 Jan 2012 00:00:00 EST

K. Tivakornsasithorn, R. E. Pimpinella, and V. Nguyen et al.
GaAs/Fe/Au core-shell nanowires were grown on GaAs(111)B substrates by molecular beam epitaxy. Scanning electron microscopy images show that the Fe shell has successfully coated the sidewalls of GaAs nanowires. Magnetic anisotropy of GaAs/Fe core-shell nanowires was studied by ferromagnetic resona ... [J. Vac. Sci. Technol. B 30, 02B115 (2012)] published Tue Jan 24, 2012.

Low resistance and thermally stable Ti/Al-based Ohmic contacts to N-face n-GaN for vertical light-emitting diodes by using Ti(Ga) solid solution and TiN layers

Tue, 24 Jan 2012 00:00:00 EST

Joon-Woo Jeon, Woong-Sun Yum, and Tae-Yeon Seong et al.
The authors report on the formation of highly reliable Ti/Al-based ohmic contacts to N-face n-GaN for high-performance vertical light-emitting diodes by using Ti(Ga) solid solution and TiN layers. The Ti(Ga) solid solution layer is used to minimize the outdiffusion of Ga atoms from the n-GaN surfa ... [J. Vac. Sci. Technol. B 30, 020601 (2012)] published Tue Jan 24, 2012.

Multi-phase model for reflection anisotropy spectra of copper phthalocyanine films on anisotropic silicon substrates

Mon, 23 Jan 2012 00:00:00 EST

Falko Seidel, Li Ding, and Ovidiu D. Gordan et al.
Reflection anisotropy spectroscopy (RAS) and spectroscopic ellipsometry (SE) have extensively been applied to inorganic and organic structures and, because of the similarity of these two techniques, the evaluation procedure of RA spectra can be performed in a similar way as for SE. Especially for ... [J. Vac. Sci. Technol. B 30, 012401 (2012)] published Mon Jan 23, 2012.

Crystallization of Ge in SiO2 matrix by femtosecond laser processing

Thu, 19 Jan 2012 00:00:00 EST

Omer Salihoglu, Ulaş Kürüm, and Halime Gul Yaglioglu et al.
Germanium nanocrystals embedded in a siliconoxide matrix has been fabricated by single femtosecond laser pulse irradiation of germanium doped SiO2 thin films deposited with plasma enhanced chemical vapor deposition. SEM and AFM are used to analyze surface modification induced by laser irradiation. ... [J. Vac. Sci. Technol. B 30, 011807 (2012)] published Thu Jan 19, 2012.

Growth of GaSb1−xBix by molecular beam epitaxy

Wed, 18 Jan 2012 00:00:00 EST

Yuxin Song, Shumin Wang, and Ivy Saha Roy et al.
Molecular beam epitaxy for GaSb1−xBix is investigated in this article. The growth window for incorporation of Bi in GaSb was found. Strategies of avoiding formation of Bi droplets and enhancing Bi incorporation were studied. The Bi incorporation was confirmed by SIMS and RBS measurements. The Bi c ... [J. Vac. Sci. Technol. B 30, 02B114 (2012)] published Wed Jan 18, 2012.

Integration of a thin film III–V edge emitting laser and a polymer microring resonator on an SiO2/Si substrate

Thu, 12 Jan 2012 00:00:00 EST

Sabarni Palit, Matthew Royal, and Nan Jokerst et al.
The planar integration of on-chip laser sources with optical sensing elements, waveguide optical interconnect, and detectors enables the implementation of portable, efficient chip-scale systems, with applications in areas that include medical, environmental, biological, and chemical sensing system ... [J. Vac. Sci. Technol. B 30, 011209 (2012)] published Thu Jan 12, 2012.

Homoepitaxial N-polar GaN layers and HEMT structures grown by rf-plasma assisted molecular beam epitaxy

Thu, 12 Jan 2012 00:00:00 EST

D. F. Storm, D. J. Meyer, and D. S. Katzer et al.
The authors have investigated the growth and structural and electrical properties of homoepitaxial GaN layers and GaN/AlGaN heterostructures grown on free-standing, hydride vapor phase epitaxy grown, N-polar GaN:Fe substrates by rf-plasma molecular beam epitaxy. Secondary-ion mass spectroscopic an ... [J. Vac. Sci. Technol. B 30, 02B113 (2012)] published Thu Jan 12, 2012.

Effects of proton irradiation energies on degradation of AlGaN/GaN high electron mobility transistors

Thu, 12 Jan 2012 00:00:00 EST

Hong-Yeol Kim, Jihyun Kim, and Lu Liu et al.
The authors report the proton energy dependence of the degradation of AlGaN/GaN high electron mobility transistors (HEMTs) with GaN cap layers from 5 to 15 MeV at a fixed dose of 5 × 1015 cm−2. All the samples degraded after proton irradiation. However, higher damage in dc electrical properties wa ... [J. Vac. Sci. Technol. B 30, 012202 (2012)] published Thu Jan 12, 2012.

Roughness optimization of electron-beam exposed hydrogen silsesquioxane for immobilization of DNA origami

Thu, 12 Jan 2012 00:00:00 EST

Faisal A. Shah, Kyoung Nan Kim, and Marya Lieberman et al.
A novel way to immobilize deoxyribonucleic acid (DNA) origami on a conventional substrate using hydrogen silsesquioxane (HSQ) as a functionalized platform is demonstrated. An alternative approach to quantifying roughness of the HSQ surfaces for 2D DNA origami immobilization is also introduced. Eff ... [J. Vac. Sci. Technol. B 30, 011806 (2012)] published Thu Jan 12, 2012.

Barrier height determination of Au/Oxidized GaAs/n-GaAs using ballistic electron emission spectroscopy

Tue, 10 Jan 2012 00:00:00 EST

Hailang Qin, Zhiqiang Liu, and Cedric Troadec et al.
Ballistic electron emission spectroscopy (BEES) was used to determine the electron barrier height at the interface of Au and an oxidized GaAs film. Two thresholds were observed in the spectra. In a two-step procedure, we identified the first threshold at ∼1.4 eV, which we show arose from electron- ... [J. Vac. Sci. Technol. B 30, 011805 (2012)] published Tue Jan 10, 2012.

Self-aligned patterning on a flexible substrate using a dual-tone, thermally activated photoresist

Tue, 10 Jan 2012 00:00:00 EST

Wei-Lun K. Jen, Brandon M. Rawlings, and Jeffrey R. Strahan et al.
The fabrication of electronic devices on flexible substrates represents an opportunity for the development of flexible display technologies, large area devices, and roll-to-roll manufacturing processes. Traditional photolithography encounters alignment and overlay limitations when applied to flexi ... [J. Vac. Sci. Technol. B 30, 011603 (2012)] published Tue Jan 10, 2012.

Analysis of defect-free GaSb/GaAs(001) quantum dots grown on the Sb-terminated (2 × 8) surface

Mon, 09 Jan 2012 00:00:00 EST

Andrew J. Martin, Timothy W. Saucer, and Kai Sun et al.
Multilayer and single layer GaSb/GaAs(001) quantum dot structures were grown on an Sb-terminated (2 × 8) surface reconstruction and compared to those grown on an As-terminated (2 × 4) surface reconstruction. Uncapped quantum dots grown on the (2 × 8) surface were approximately 25% smaller in diame ... [J. Vac. Sci. Technol. B 30, 02B112 (2012)] published Mon Jan 09, 2012.

Photoluminescence study of self-assembled GaAs quantum wires on (631)A-oriented GaAs substrates

Mon, 09 Jan 2012 00:00:00 EST

E. Cruz-Hernández, D. Vázquez-Cortés, and A. Cisneros-de-la-Rosa et al.
The authors report a low-temperature photoluminescence (PL) study of multiple GaAs layers grown between AlAs(0.6 nm)/GaAs(0.6 nm) short-period superlattice barriers (SLBs) simultaneously grown on both GaAs(631)A and (100) substrates. Five GaAs-layers of different nominal thicknesses (LW, ranging f ... [J. Vac. Sci. Technol. B 30, 02B111 (2012)] published Mon Jan 09, 2012.

Effect of ballast-resistor and field-screening on electron-emission from nanodiamond emitters fabricated on micropatterned silicon pillar arrays

Fri, 06 Jan 2012 00:00:00 EST

N. Ghosh, W. P. Kang, and J. L. Davidson et al.
This paper describes the influence of ballast-resistor and field-screening on the electron field-emission behavior of nanodiamond emitter arrays fabricated on micropatterned silicon pillars. Arrays of 50 × 50 silicon pillars capped with nanodiamond with different ballast resistances and pillar sep ... [J. Vac. Sci. Technol. B 30, 012201 (2012)] published Fri Jan 06, 2012.

Deep anisotropic LiNbO3 etching with SF6/Ar inductively coupled plasmas

Fri, 06 Jan 2012 00:00:00 EST

Deng Jun, Jia Wei, and Ching Eng Png et al.
A SF6/Ar inductively coupled plasma (ICP) technique was investigated to improve etching of proton exchanged LiNbO3. The influences of He backside cooling, power, and gas flows on characteristics such as etching rate, sidewall slope angle, and surface roughness were investigated. Total gas flow is ... [J. Vac. Sci. Technol. B 30, 011208 (2012)] published Fri Jan 06, 2012.

Strategy for focused ion beam compound material removal for circuit editing

Fri, 06 Jan 2012 00:00:00 EST

Yariv Drezner, Yuval Greenzweig, and Amir Raveh
Both selective and nonselective focused ion beam (FIB) processes have become critical for enabling fine-scale activities such as nano-machining and nano-fabrication in compound material removal applications. In this paper, we investigate the influence of FIB ion acceleration voltage on gas assiste ... [J. Vac. Sci. Technol. B 30, 011207 (2012)] published Fri Jan 06, 2012.

Fabrication of stable and reproducible submicron tunnel junctions

Fri, 06 Jan 2012 00:00:00 EST

I. M. Pop, T. Fournier, and T. Crozes et al.
The authors have performed a detailed study of the time stability and reproducibility of submicron Al/AlOx/Al tunnel junctions, fabricated using standard double angle shadow evaporations. The authors have found that by aggressively cleaning the substrate before the evaporations; thus preventing an ... [J. Vac. Sci. Technol. B 30, 010607 (2012)] published Fri Jan 06, 2012.

Rare-earth-metal oxide buffer for epitaxial growth of single crystal GeSi and Ge on Si(111)

Wed, 28 Dec 2011 00:00:00 EST

Rytis Dargis, Erdem Arkun, and Andrew Clark et al.
Ternary and binary rare-earth oxides that are used as a template buffer, which accommodates the crystal lattice mismatch between substrate and a semiconductor layer, are discussed here. The oxides were grown on Si(111) substrates and exhibit the cubic bixbyite crystal structure. Stabilization of t ... [J. Vac. Sci. Technol. B 30, 02B110 (2012)] published Wed Dec 28, 2011.

Molecular beam epitaxy control and photoluminescence properties of InAsBi

Tue, 27 Dec 2011 00:00:00 EST

S. P. Svensson, H. Hier, and W. L. Sarney et al.
Thick InAsBi layers were grown for photoluminescence (PL) characterization. The As to In overpressure ratio was carefully characterized and adjusted to achieve Bi-droplet-free surfaces. A closed loop feedback system was used to maintain the As overpressure during a 5-h deposition sequence. Despite ... [J. Vac. Sci. Technol. B 30, 02B109 (2012)] published Tue Dec 27, 2011.

Interface properties of (In,Ga)As/GaAs quantum wells grown by solid-phase epitaxy

Tue, 27 Dec 2011 00:00:00 EST

E. Luna, R. Hey, and A. Trampert
(In,Ga)As/GaAs quantum wells (QWs) are successfully fabricated via a thermally induced structural transition from deposited amorphous material to epitaxial films, also known as solid-phase epitaxy (SPE). Although exact processes occurring during the epilayer formation are unknown, it is shown that ... [J. Vac. Sci. Technol. B 30, 02B108 (2012)] published Tue Dec 27, 2011.

Directed assembly in epitaxial zinc oxide films on focused ion beam modified sapphire substrates

Thu, 22 Dec 2011 00:00:00 EST

Benjamin D. Myers, Blake L. Stevens, and Dorota I. Rożkiewicz et al.
A new method for directed self-assembly using focused ion beam (FIB) and physical vapor deposition is presented. The high resolution and site-specific patterning capabilities of FIB are coupled with the self-assembly process in heteroepitaxial thin film growth. An efficient FIB-induced damage mech ... [J. Vac. Sci. Technol. B 30, 010605 (2012)] published Thu Dec 22, 2011.

Carbon monoxide detection sensitivity of ZnO nanorod-gated AlGaN/GaN high electron mobility transistors in different temperature environments

Thu, 22 Dec 2011 00:00:00 EST

Chien-Fong Lo, Lu Liu, and Byung-Hwan Chu et al.
The effect of ambient temperature on the detection sensitivity of carbon monoxide (CO) using ZnO nanorod-gated AlGaN/GaN high electron mobility transistor (HEMT) sensors was studied over a range of temperatures from 25 to 400 °C. An increase of the HEMT drain current was observed for exposure to t ... [J. Vac. Sci. Technol. B 30, 010606 (2012)] published Thu Dec 22, 2011.

Role of ions, photons, and radicals in inducing plasma damage to ultra low-k dielectrics

Thu, 22 Dec 2011 00:00:00 EST

Hualiang Shi, Huai Huang, and Junjing Bao et al.
The damage induced by CO2 and O2 plasmas to an ultra low-k (ULK) dielectric film with a dielectric constant (κ) of 2.2 was investigated. The dielectric constant was observed to increase due to methyl depletion, moisture uptake, and surface densification. A gap structure was used to delineate the r ... [J. Vac. Sci. Technol. B 30, 011206 (2012)] published Thu Dec 22, 2011.

Determination of crystal orientation of silicon via shape-controlled vapor-solid growth of copper nanoparticles

Wed, 21 Dec 2011 00:00:00 EST

Jin-Woo Han and M. Meyyappan
Crystal lattice orientations of substrates are inspected via morphology of copper particles generated by a vapor-solid growth process. The high thermal energy enables diffusion of copper ions into the crystal substrate, and then the copper ions on the substrate are preferentially gathered, forming ... [J. Vac. Sci. Technol. B 30, 010604 (2012)] published Wed Dec 21, 2011.