Center for Quantum Devices - Most Downloaded Journal Articles

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18.	Optoelectronic Devices Based on III-V Compound Semiconductors Which Have Made a Major Scientific and Technological Impact in the Past 20 Years M. Razeghi IEEE Journal of Selected Topics in Quantum Electronics 6 (6), pp.1344 - 1354 -- November 1, 2000 ...[Visit Journal] This paper reviews some of our pioneering contributions to the field of III–V compound semiconductor materials and low-dimensional optoelectronic devices. These contributions span from the ultraviolet (200 nm) up to the far-infrared (25 μm) portion of the electromagnetic spectrum and have had a major scientific and technological impact on the semiconductor world in the past 20 years. [reprint (PDF)]
18.	Thermal stability of GaN thin films grown on (0001) Al₂O₃, (0112) Al₂O₃ and (0001)Si 6H-SiC substrates C.J. Sun, P. Kung, A. Saxler, H. Ohsato, E. Bigan, M. Razeghi, and D.K. Gaskill Journal of Applied Physics 76 (1)-- July 1, 1994 ...[Visit Journal] Single crystals of GaN were grown on (0001), (0112) Al₂O₃ and (0001)Si 6H‐SiC substrates using an atmospheric pressure metalorganic chemical‐vapor‐deposition reactor. The relationship has been studied between the thermal stability of the GaN films and the substrate’s surface polarity. It appeared that the N‐terminated (0001) GaN surface grown on (0001)Si 6H‐SiC has the most stable surface, followed by the nonpolar (1120) GaN surface grown on (0112) Al₂O₃, while the Ga‐terminated (0001) GaN surface grown on (0001) Al₂O₃ has the least stable surface. This is explained with the difference in the atomic configuration of each of these surfaces which induces a difference in their thermal decomposition. [reprint (PDF)]
18.	Widely tunable room temperature semiconductor terahertz source Q. Y. Lu, S. Slivken, N. Bandyopadhyay, Y. Bai, and M. Razeghi Appl. Phys. Lett. 105, 201102-- November 17, 2014 ...[Visit Journal] We present a widely tunable, monolithic terahertz source based on intracavity difference frequency generation within a mid-infrared quantum cascade laser at room temperature. A three-section ridge waveguide laser design with two sampled grating sections and a distributed-Bragg section is used to achieve the terahertz (THz) frequency tuning. Room temperature single mode THz emission with a wide tunable frequency range of 2.6–4.2 THz (∼47% of the central frequency) and THz power up to 0.1 mW is demonstrated, making such device an ideal candidate for THz spectroscopy and sensing. [reprint (PDF)]
18.	Gas sensing spectroscopy system utilizing a sample grating distributed feedback quantum cascade laser array and type II superlattice detector Nathaniel R. Coirier; Andrea I. Gomez-Patron; Manijeh Razeghi Proc. SPIE 11288, Quantum Sensing and Nano Electronics and Photonics XVII, 1128815-- January 31, 2020 ...[Visit Journal] Gas spectroscopy is a tool that can be used in a variety of applications. One example is in the medical field, where it can diagnose patients by detecting biomarkers in breath, and another is in the security field, where it can safely alert personnel about ambient concentrations of dangerous gas. In this paper, we document the design and construction of a system compact enough to be easily deployable in defense, healthcare, and chemical safety environments. Current gas sensing systems use basic quantum cascade lasers (QCLs) or distributed feedback quantum cascade lasers (DFB QCLs) with large benchtop signal recovery systems to determine gas concentrations. There are significant issues with these setups, namely the lack of laser tunability and the lack of practicality outside of a very clean lab setting. QCLs are advantageous for gas sensing purposes because they are the most efficient lasers at the mid infrared region (MIR). This is necessary since gases tend to have stronger absorption lines in the MIR range than in the near-infrared (NIR) region. To incorporate the efficiency of a QCL with wide tuning capabilities in the MIR region, sampled grating distributed feedback (SGDFB) QCLs are the answer as they have produced systems that are widely tunable, which is advantageous for scanning a robust and complete absorption spectrum. The system employs a SGDFB QCL array emitter, a Type II InAsSb Superlattice detector receiver, a gas cell, and a cooling system. [reprint (PDF)]
18.	High power frequency comb based on mid-infrared quantum cascade laser at λ ~9μm Q. Y. Lu, M. Razeghi, S. Slivken, N. Bandyopadhyay, Y. Bai, W. J. Zhou, M. Chen, D. Heydari, A. Haddadi, R. McClintock, M. Amanti, and C. Sirtori Appl. Phys. Lett. 106, 051105-- February 2, 2015 ...[Visit Journal] We investigate a frequency comb source based on a mid-infrared quantum cascade laser at λ ∼9 μm with high power output. A broad flat-top gain with near-zero group velocity dispersion has been engineered using a dual-core active region structure. This favors the locking of the dispersed Fabry-Pérot modes into equally spaced frequency lines via four wave mixing. A current range with a narrow intermode beating linewidth of 3 kHz is identified with a fast detector and spectrum analyzer. This range corresponds to a broad spectral coverage of 65 cm⁻¹ and a high power output of 180 mW for ∼176 comb modes. [reprint (PDF)]
18.	High-brightness LWIR quantum cascade lasers F. Wang, S. Slivken, and M. Razeghi F. Wang, S. Slivken, and M. Razeghi, High-brightness LWIR quantum cascade lasers, Optics Letters, vol. 46, No. 20, 5193 ...[Visit Journal] Long-wave infrared (LWIR, lambda~8-12 um) quantum cascade lasers (QCLs) are drawing increasing interest, as they provide the possibility of long-distance transmission of light through the atmosphere owing to the reduced water absorption. However, their development has been lagging behind the shorter wavelength QCLs due to much bigger technological challenges. In this Letter, through band structure engineering based on a highly localized diagonal laser transition strategy and out-coupler design using an electrically isolated taper structure, we demonstrate high beam quality single-mode LWIR QCLs with high-brightness (2.0 MW cm^-2 sr^-1 for lambda~10 um, 2.2 MW cm^-2 sr^-1 for lambda~9 um, 5.0 MW cm^-2 sr^-1 for lambda~8 um) light extraction from a single facet in continuous-wave operation at 15 ^oC. These results mark an important milestone in exploring the lighting capability of inter-sub-band semiconductor lasers in the LWIR spectral range. [reprint (PDF)]
18.	Gas Source Molecular Beam Epitaxy Growth and Characterization of Ga_0.51In_0.49P/In_xGa_1-xAs/GaAs Modulation-doped Field-effect Transistor Structures C. Besikci, Y. Civan, S. Ozder, O. Sen, C. Jelen, S. Slivken, and M. Razeghi Semiconductor Science Technology 12-- January 1, 1997 ...[Visit Journal] Lattice-matched Ga_0.51In_0.49P/GaAs and strained Ga_0.51In_0.49P/In_xGa_1−xAs/GaAs (0.1 ≤ x ≤ 0.25) modulation-doped field-effect transistor structures were grown by gas source molecular beam epitaxy by using Si as dopant. Detailed electrical characterization results are presented. The Ga_0.5In_0.49P/In_0.25Ga_0.75As/GaAs sample yielded dark two-dimensional electron gas densities of 3.75 x 10¹² cm^-2 (300 K) and 2.3 x 10¹² cm^-2 (77 K) which are comparable to the highest sheet electron densities reported in AlGaAs/InGaAs/GaAs and InAlAs/InGaAs/InP modulation-doped heterostructures. Persistent photoconductivity was observed in the strained samples only. A 0.797 eV deep level has been detected in the undoped GaInP layers of the structures. Another level, with DLTS peak height dependent on the filling pulse width, has been detected at the interface of the strained samples. Based on the DLTS and Hall effect measurement results, this level, which seems to be the origin of persistent photoconductivity, can be attributed to the strain relaxation related defects. [reprint (PDF)]
18.	Novel Sb-based Alloys for Uncooled Infrared Photodetector Applications M. Razeghi SPIE Conference, San Jose, CA, -- January 22, 2001 ...[Visit Journal] We report on the growth and characterization of InSbBi, InTlSb, InTlP, and the quaternary alloys for uncooled long- wavelength infrared photodetector applications. The layers were grown on InSb and GaAs substrates by low-pressure metalorganic chemical vapor deposition. The incorporation of Bi and Tl in InSb was investigated with high-resolution x-ray diffraction, energy dispersive x-ray analysis, and optical photoresponse measurements. We also demonstrate the photodetectors fabricated from the grown InSbBi and InTlSb alloys. InSb_0.96Bi_0.04 photoconductive detectors exhibited a responsivity of 3.2 V/W at 77 K. The estimated Johnson noise limited detectivityat 7 micrometers was 1.7 X 10⁸ cm·Hz^½/W at 77 K. A room temperature operating InSb_0.95Bi_0.05 photodetector was also demonstrated.Photoresponse up to 12 micrometers was achieved at 300 K. The responsivity and Johnson noise-limited detectivity at 10.6 μm were 1.9 mV/W and 1.2 X 10⁶ cm·Hz^½/W, respectively. Photoresponse up to 15 μm was achieved at 300 K from quaternary InTlAsSb and InBiAsSb alloys. [reprint (PDF)]
18.	High power operation of λ ∼ 5.2–11 μm strain balanced quantum cascade lasers based on the same material composition N. Bandyopadhyay, Y. Bai, S. Slivken, and M. Razeghi Appl. Phys. Lett. 105, 071106 (2014)-- August 20, 2014 ...[Visit Journal] A technique based on composite quantum wells for design and growth of strain balanced Al_0.63In_0.37As/Ga_0.35In_0.65As/Ga_0.47In_0.53As quantum cascade lasers (QCLs) by molecular beam epitaxy (MBE), emitting in 5.2–11 μm wavelength range, is reported. The strained Al_0.63In_0.37As provides good electron confinement at all wavelengths, and strain balancing can be achieved through composite wells of Ga_0.35In_0.65As/Ga_0.47In_0.53As for different wavelength. The use of these fixed composition materials can avoid the need for frequent calibration of a MBE reactor to grow active regions with different strain levels for different wavelengths. Experimental results for QCLs emitting at 5.2, 6.7, 8.2, 9.1, and 11 μm exhibit good wall plug efficiencies and power across the whole wavelength range. It is shown that the emission wavelength can be predictably changed using the same design template. These lasers are also compatible with a heterogeneous broadband active region, consisting of multiple QCL cores, which can be produced in a single growth run. [reprint (PDF)]
18.	Photoluminescence characteristics of polar and nonpolar AlGaN/GaN superlattices Z. Vashaei, C. Bayram, P. Lavenus, and M. Razeghi Applied Physics Letters, Vol. 97, No. 12, p. 121918-1-- September 20, 2010 ...[Visit Journal] High quality Al_0.2Ga_0.8N/GaN superlattices (SLs) with various (GaN) well widths (1.6 to 6.4 nm) have been grown on polar c-plane and nonpolar m-plane freestanding GaN substrates by metal-organic chemical vapor deposition. Atomic force microscopy, high resolution x-ray diffraction, and photoluminescence (PL) studies of SLs have been carried out to determine and correlate effects of well width and polarization field on the room-temperature PL characteristics. A theoretical model was applied to explain PL energy-dependency on well width and crystalline orientation taking into account internal electric field for polar substrate. Absence of induced-internal electric field in nonpolar SLs was confirmed by stable PL peak energy and stronger PL intensity as a function of excitation power density than polar ones. [reprint (PDF)]
18.	Demonstration of mid-infrared type-II InAs/GaSb superlattice photodiodes grown on GaAs substrate B.M. Nguyen, D. Hoffman, E.K. Huang, S. Bogdanov, P.Y. Delaunay, M. Razeghi and M.Z. Tidrow Applied Physics Letters, Vol. 94, No. 22-- June 8, 2009 ...[Visit Journal] We report the growth and characterization of type-II InAs/GaSb superlattice photodiodes grown on a GaAs substrate. Through a low nucleation temperature and a reduced growth rate, a smooth GaSb surface was obtained on the GaAs substrate with clear atomic steps and low roughness morphology. On the top of the GaSb buffer, a p⁺-i-n⁺ type-II InAs/GaSb superlattice photodiode was grown with a designed cutoff wavelength of 4 μm. The detector exhibited a differential resistance at zero bias (R₀A)in excess of 1600 Ω·cm² and a quantum efficiency of 36.4% at 77 K, providing a specific detectivity of 6 X 10¹¹ cm·Hz^½/W and a background limited operating temperature of 100 K with a 300 K background. Uncooled detectors showed similar performance to those grown on GaSb substrates with a carrier lifetime of 110 ns and a detectivity of 6 X 10⁸ cm·Hz^½/W. [reprint (PDF)]
18.	Continuous-wave operation of λ ~ 4.8 µm quantum-cascade lasers at room temperature A. Evans, J.S. Yu, S. Slivken, and M. Razeghi Applied Physics Letters, 85 (12)-- September 20, 2004 ...[Visit Journal] Continuous-wave (cw) operation of quantum-cascade lasers emitting at λ~4.8 µm is reported up to a temperature of 323 K. Accurate control of layer thickness and strain-balanced material composition is demonstrated using x-ray diffraction. cw output power is reported to be in excess of 370 mW per facet at 293 K, and 38 mW per facet at 323 K. Room-temperature average power measurements are demonstrated with over 600 mW per facet at 50% duty cycle with over 300 mW still observed at 100% (cw) duty cycle. [reprint (PDF)]
18.	Comparison of ultraviolet light-emitting diodes with peak emission at 340 nm grown on GaN substrate and sapphire A. Yasan, R. McClintock, K. Mayes, S.R. Darvish, H. Zhang, P. Kung, M. Razeghi, S.K. Lee and J.Y. Han Applied Physics Letters, 81 (12)-- September 16, 2002 ...[Visit Journal] Based on AlInGaN/AlInGaN multiquantum wells, we compare properties of ultraviolet light-emitting diodes (LED) with peak emission at 340 nm grown on free-standing hydride vapor phase epitaxially grown GaN substrate and on sapphire. For the LED grown on GaN substrate, a differential resistance as low as 13 Ω and an output power of more than one order of magnitude higher than that of the same structure grown on sapphire are achieved. Due to higher thermal conductivity of GaN, output power of the LEDs saturates at higher injection currents compared to the devices grown on sapphire. [reprint (PDF)]
18.	Recent Advances in Room Temperature, High-Power Terahertz Quantum Cascade Laser Sources Based on Difference-Frequency Generation Quanyong Lu and Manijeh Razeghi Photonics, 3, 42-- July 7, 2016 ...[Visit Journal] We present the current status of high-performance, compact, THz sources based on intracavity nonlinear frequency generation in mid-infrared quantum cascade lasers. Significant performance improvements of our THz sources in the power and wall plug efficiency are achieved by systematic optimizing the device’s active region, waveguide, and chip bonding strategy. High THz power up to 1.9 mW and 0.014 mW for pulsed mode and continuous wave operations at room temperature are demonstrated, respectively. Even higher power and efficiency are envisioned based on enhancements in outcoupling efficiency and mid-IR performance. Our compact THz device with high power and wide tuning range is highly suitable for imaging, sensing, spectroscopy, medical diagnosis, and many other applications. [reprint (PDF)]
18.	EPR STUDY OF Mn 2. AROUND THE FERROELASTIC TRANSITION POINT OF Pb3(PO4)2 M. Razeghi, B. Houlier and M. Yuste M. Razeghi et al. EPR STUDY OF Mn 2. AROUND THE FERROELASTIC TRANSITION POINT OF Pb3(PO4)2, Solid State Communications, Vol. 26, pp. 665-668. -- January 26, 1978 ...[Visit Journal] The spin Hamiltonian parameters of Mn 2÷ have been measured above and below the transition point (180"C) of the lead phosphate. They show that Mn 2+ substitutes a Pbl ion. Between 175 and 180vC the principal axis OX of the fine tensor is parallel to the wave vector of the soft mode which condensates at the transition point. An exaltation of the linewidth is observed. The linewidth remains constant within 50C of Te; in this temperature range, the "static regime" is achieved, and the correlation time of the fluctuations is less than 10 -s sec. [reprint (PDF)]
18.	Type-II InAs/GaSb superlattice photovoltaic detectors with cutoff wavelength approaching 32 μm Y. Wei, A. Gin, M. Razeghi and G.J. Brown Applied Physics Letters, 81 (19)-- November 4, 2002 ...[Visit Journal] We report the most recent advance in the area of type-II InAs/GaSb superlattice photovoltaic detectors that have cutoff wavelengths beyond 25 μm, with some at nearly 32 μm. The photodiodes with a heterosuperlattice junction showed Johnson noise limited peak detectivity of 1.05 x 10¹⁰ cm Hz^½/W at 15 μm under zero bias, and peak responsivity of 3 A/W under -40 mV reverse bias at 34 K illuminated by ~300 K background with a 2π field-of-view. The maximum operating temperature of these detectors ranges from 50 to 65 K. No detectable change in the blackbody response has been observed after 5-6 thermal cyclings, with temperature varying between 15 and 296 K in vacuum. [reprint (PDF)]
18.	Comparison of Gain and Threshold Current Density for InGaAsP/GaAs λ = 808 nm) Lasers with Different Quantum-Well Thickness H.J. Yi, J. Diaz, I. Eliashevich, G. Lukas, S. Kim, D. Wu, M. Erdtmann, C. Jelen, S. Slivken, L.J. Wang, and M. Razeghi Journal of Applied Physics 79 (11)-- July 1, 1996 ...[Visit Journal] We investigated the quantum‐size effects of quantum well (QW) on gain and threshold current density for InGaAsP/GaAs (λ=808 nm) laser diodes. In this work, a comparison is made of lasers with different QW thickness while keeping the optical confinement factors constant. We found that the threshold current density and differential efficiency were not affected by narrowing the QW thickness. The theoretical model taking into account the mixing of the valence bands and momentum relaxation for InGaAsP/GaAs lasers with spontaneous emission (optically pumped) measurement shows that the absence of difference between these structures can be attributed to the high relaxation rate. [reprint (PDF)]
18.	Antimonide-Based Type II Superlattices: A Superior Candidate for the Third Generation of Infrared Imaging Systems M. Razeghi, A. Haddadi, A.M. Hoang, G. Chen, S. Bogdanov, S.R. Darvish, F. Callewaert, P.R. Bijjam, and R. McClintock Journal of ELECTRONIC MATERIALS, Vol. 43, No. 8, 2014-- August 1, 2014 ...[Visit Journal] Type II superlattices (T2SLs), a system of interacting multiquantum wells,were introduced by Nobel Laureate L. Esaki in the 1970s. Since then, this material system has drawn a lot of attention, especially for infrared detection and imaging. In recent years, the T2SL material system has experienced incredible improvements in material growth quality, device structure design, and device fabrication techniques that have elevated the performance of T2SL-based photodetectors and focal-plane arrays (FPAs) to a level comparable to state-of-the-art material systems for infrared detection and imaging, such as mercury cadmium telluride compounds. We present the current status of T2SL-based photodetectors and FPAs for imaging in different infrared regimes, from short wavelength to very long wavelength, and dual-band infrared detection and imaging, as well as the future outlook for this material system. [reprint (PDF)]
18.	Optoelectronic Integrated Circuits (OEICs) for Next Generation WDM Communications M. Razeghi and S. Slivken SPIE Conference, Boston, MA, -- July 29, 2002 ...[Visit Journal] This paper reviews some of the key enabling technologies for present and future optoelectronic intergrated circuits. This review concentrates mainly on technology for lasers, waveguides, modulators, and fast photodetectors as the basis for next generation communicatiosn systems. Emphasis is placed on intergrations of components and mass production of a generic intelligent tranciever. [reprint (PDF)]
17.	Status of III-V semiconductor thin films and their applications to future OEICs Manijeh Razeghi Proc. SPIE 10267, Integrated Optics and Optoelectronics, 102670T -- June 26, 2017 ...[Visit Journal] In the last decade, semiconductor technology has been advanced to a great extent in terms of electronic and photonic discrete devices. One of the main reasons for such a progress, is the result of advancement in the epitaxial growth techniques such as molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD), where device quality films can be grown with great control over composition, uniformity and thickness. MOCVD has proven to be one of the best growth methods for many IH-V semiconductor thin films 1. Its flexibility and potential to yield a broad range of growth rates resulted in the layers featuring the thicknesses from tens of microns down to several nanometers. Planar structures containing quantum wells with atomically flat interfaces, superlattices, strained or graded-index layers were successfully grown by MOCVD. Furthermore, MOCVD proved its efficiency in producing a laser devices by overgrowth and epitaxy on patterned substrates. The importance of MOCVD is strongly enhanced by the possibility of large-scale production by simultaneous growth on several substrates in one process. Several III-V semiconductor films with bandgaps ranging from infrared to ultraviolet (15 to 0.2 μm) have been successfully grown by MOCVD. [reprint (PDF)]
17.	RT-CW: widely tunable semiconductor THz QCL sources M. Razeghi; Q. Y. Lu Proceedings Volume 9934, Terahertz Emitters, Receivers, and Applications, 993406-1-- September 26, 2017 ...[Visit Journal] Distinctive position of Terahertz (THz) frequencies (ν~0.3 -10 THz) in the electromagnetic spectrum with their lower quantum energy compared to IR and higher frequency compared to microwave range allows for many potential applications unique to them. Especially in the security side of the THz sensing applications, the distinct absorption spectra of explosives and related compounds in the range of 0.1–5 THz makes THz technology a competitive technique for detecting hidden explosives. A compact, high power, room temperature continuous wave terahertz source emitting in a wide frequency range will greatly boost the THz applications for the diagnosis and detection of explosives. Here we present a new strong-coupled strain-balanced quantum cascade laser design for efficient THz generation based intracavity DFG. Room temperature continuous wave operation with electrical frequency tuning range of 2.06-4.35 THz is demonstrated [reprint (PDF)]
17.	Semiconductor ultraviolet detectors M. Razeghi and A. Rogalski SPIE Photonics West '96 Photodetectors: Materials and Devices; Proceedings 2685-- January 27, 1996 ...[Visit Journal] This paper presents an overview of semiconductor ultraviolet (UV) detectors that are currently available and associated technologies that are undergoing further development. At the beginning, the classification of UV detectors and general requirements imposed on these detectors are presented. Further consideration are restricted to modern semiconductor UV detectors, so the current state-of-the-art of different types of semiconductor UV detectors is presented. Hitherto, the semiconductor UV detectors have been mainly fabricated using Si. Industries such as the aerospace, automotive, petroleum, and others have continuously provided the impetus pushing the development of fringe technologies which are tolerant of increasingly high temperatures and hostile environments. As a result, the main effort are currently directed to a new generation of UV detectors fabricated from wide-band-gap semiconductors between them the most promising are diamond and AlGaN. The latest progress in development of AlGaN UV detectors is finally described in detail. [reprint (PDF)]
17.	Growth of InAsSb Alloys on GaAs and Si Substrates for Uncooled Infrared Photodetector Applications J.D. Kim, H. Mohseni, J.S. Wojkowski, J.J. Lee and M. Razeghi SPIE Conference, San Jose, CA, -- January 27, 1999 ...[Visit Journal] In this paper, we report on the growth and characterization of InAsSb alloys on GaAs and Si substrates for uncooled infrared photodetector applications. The fabrication and characterization of photodetectors from the grown layers are also reported. The photovoltaic and photoconductive devices were grown on (100) GaAs and Si substrates, respectively, using molecular beam epitaxy (MBE). The composition of InAs>sub>1-xSb_x layers was 0.95 in both cases and cut-off wavelength of 7-8 μm has been obtained. At 300 K, the photovoltaic detectors on GaAs substrates resulted in a sharp cut-off wavelength of 7.5 μm with a peak responsivity as high as 0.32 V/W at 6.5 micrometer. For the photoconductive detectors on Si substrates, cut-off wavelength of 8 μm has been observed with a responsivity of 6.3x10^-2 V/W at 7 μm under an electric field of 420 V/m. [reprint (PDF)]
17.	High Frequency Extended Short-Wavelength Infrared Heterojunction Photodetectors Based on InAs/GaSb/AlSb Type-II Superlattices Romain Chevallier, Abbas Haddadi, Ryan McClintock, Arash Dehzangi , Victor Lopez-Dominguez, Pedram Khalili Amiri, Manijeh Razeghi IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 54, NO. 6-- December 1, 2018 ...[Visit Journal] InAs/GaSb/AlSb type-II superlattice-based photodetectors, with 50% cut-off wavelength of 2.1 µm and a −3 dB cut-off frequency of 4.8 GHz, are demonstrated, for 10 µm diameter circular mesas under 15 V applied reverse bias. A study of the cut-off frequency with applied bias and mesa size was performed to evaluate some of the limiting factors of photodetectors high frequency performance. [reprint (PDF)]
17.	Techniques for High-Quality SiO₂ Films J. Nguyen and M. Razeghi SPIE Conference, January 25-29, 2007, San Jose, CA Proceedings – Quantum Sensing and Nanophotonic Devices IV, Vol. 6479, p. 64791K-1-8-- January 29, 2007 ...[Visit Journal] We report on the comparison of optical, structural, and electrical properties of SiO₂ using plasma-enhanced chemical vapor deposition and ion-beam sputtering deposition. High-quality, low-temperature deposition of SiO₂ by ion-beam sputtering deposition is shown to have lower absorption, smoother and more densely packed films, a lower amount of fixed oxide charges, and a lower trapped-interface density than SiO₂ by plasma-enhanced chemical vapor deposition. This high-quality SiO₂ is then demonstrated as an excellent electrical and mechanical surface passivation layer on Type-II InAs/GaSb photodetectors [reprint (PDF)]

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