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| 18. | InGaAlAs/InP Quantum Well Infrared Photodetectors for 8-20 μm Wavelengths C. Jelen, S. Slivken, V. Guzman, M. Razeghi, and G. Brown IEEE Journal of Quantum Electronics 34 (10)-- October 1, 1998 ...[Visit Journal] We demonstrate the first long-wavelength quantum-well infrared photodetectors using the lattice-matched n-doped InGaAlAs-InP materials system. Samples with AlAs mole fractions of 0.0, 0.1, and 0.15 result in cutoff wavelengths of 8.5, 13.3, and 19.4 mu m, respectively. A 45 degrees facet coupled illumination. responsivity of R = 0.37 A/W and detectivity of D-lambda* = 3 x 10(8) cm .root Hz . W-1 at T = K, for a cutoff wavelength lambda(c) = 13.3 mu m have been achieved. Based on the measured intersubband photoresponse wavelength, a null conduction band offset is expected for In0.52Ga0.21Al0.27As-InP heterojunctions. [reprint (PDF)] |
| 18. | Review of high power frequency comb sources based on InP From MIR to THZ at CQD Manijeh Razeghi, Quanyong Lu, Donghai Wu, Steven Slivken Event: SPIE Optical Engineering + Applications, 2018, San Diego, California, United States-- September 14, 2018 ...[Visit Journal] We present the recent development of high performance compact frequency comb sources based on mid-infrared quantum cascade lasers. Significant performance improvements of our frequency combs with respect to the continuous wave power output, spectral bandwidth, and beatnote linewidth are achieved by systematic optimization of the device's active region, group velocity dispersion, and waveguide design. To date, we have demonstrated the most efficient, high power frequency comb operation from a free-running room temperature continuous wave (RT CW) dispersion engineered QCL at λ~5-9
μm. In terms of bandwidth, the comb covered a broad spectral range of 120 cm−1 with a radio-frequency intermode beatnote spectral linewidth of 40 Hz and a total power output of 880 mW at 8 μm and 1 W at ~5.0 μm. The developing characteristics show the potential for fast detection of various gas molecules. Furthermore, THz comb sources based on difference frequency generation in a mid-IR QCL combs could be potentially developed. [reprint (PDF)] |
| 18. | High-performance InP-based midinfrared quantum cascade lasers at Northwestern University M. Razeghi, Y. Bai, S. Slivken, and S.R. Darvish SPIE Optical Engineering, Vol. 49, No. 11, November 2010, p. 111103-1-- November 15, 2010 ...[Visit Journal] We present recent performance highlights of midinfrared quantum cascade lasers (QCLs) based on an InP material system. At a representative wavelength around 4.7 µm, a number of breakthroughs have been achieved with concentrated effort. These breakthroughs include watt-level continuous wave operation at room temperature, greater than 50% peak wall plug efficiency at low temperatures, 100-W-level pulsed mode operation at room temperature, and 10-W-level pulsed mode operation of photonic crystal distributed feedback quantum cascade lasers at room temperature. Since the QCL technology is wavelength adaptive in nature, these demonstrations promise significant room for improvement across a wide range of mid-IR wavelengths. [reprint (PDF)] |
| 18. | Two-dimensional magnetophonon resonance in GaInAs-InP and GaInAs-AlInAs heterojunctions and superlattices J.C. Portal, G. Gregoris a b , M.A. Brummell , R.J. Nicholas, M. Razeghi, M.A. Di Forte-Poisson, K.Y. Cheng, A.Y. Cho J.C. Portal, G. Gregoris, M.A. Brummell, R.J. Nicholas, M. Razeghi, M.A. Di Forte-Poisson, K.Y. Cheng, A.Y. Cho, Two-dimensional magnetophonon resonance in GaInAs-InP and GaInAs-AlInAs heterojunctions and superlattices, Surface Science, Volume 142, Issues 1–3, 1984, Pages 368-374,-- July 1, 1984 ...[Visit Journal] We report the observation of magnetophonon resonance in GaInAs-InP heterojunctions and measurements of the temperature dependence of the oscillations. A single series of oscillations due to scattering by the “GaAs-like” mode of GaInAs is seen, in contrast to GaInAs-InP superlattices, where scattering from InP phonons is also observed, and GaInAs-AlInAs heterojunctions, where coupling to “InAs-like” modes only is seen. This behaviour is discussed in terms of long-range phonon interactions and interface phonons.
[reprint (PDF)] |
| 18. | Room-temperature continuous-wave operation of quantum-cascade lasers at λ ~ 4 µm J.S. Yu, S.R. Darvish, A. Evans, J. Nguyen, S. Slivken, and M. Razeghi Applied Physics Letters 88 (4)-- January 23, 2006 ...[Visit Journal] High-power cw λ~4 μm quantum-cascade lasers (QCLs) are demonstrated. The effect of different cavity length and laser die bonding is also investigated. For a high-reflectivity-coated 11-μm-wide and 4-mm-long epilayer-down bonded QCL, cw output powers as high as 1.6 W at 80 K and 160 mW at 298 K are obtained, and the cw operation is achieved up to 313 K with 12 mW. [reprint (PDF)] |
| 18. | High performance monolithic, broadly tunable mid-infrared quantum cascade lasers WENJIA Zhou, DONGHAI Wu, RYAN McCLINTOCK, STEVEN SLIVKEN, AND MANIJEH RAZEGH1 Optica 4(10), p. 1228-- October 10, 2017 ...[Visit Journal] Mid-infrared lasers, emitting in the spectral region of 3-12 µm that contains strong characteristic vibrational transitions of many important molecules, are highly desirable for spectroscopy sensing applications. High-efficiency quantum cascade lasers have been demonstrated with up to watt-level output power in the mid-infrared region. However, the wide wavelength tuning that is critical for spectroscopy applications still largely relies on incorporating external gratings, which have stability issues. Here, we demonstrate a monolithic, broadly tunable quantum cascade laser source emitting between 6.1 and 9.2 µm through an on-chip integration of a sampled grating distributed feedback tunable laser array and a beam combiner. High peak power up to 65 mW has been obtained through a balanced high-gain active region design, efficient waveguide layout, and the development of a broadband antireflection coating. Nearly fundamental transversemode operation is achieved for all emission wavelengths with a pointing stability better than 1.6 mrad (0.1 °). The demonstrated laser source opens new opportunities for mid-infrared spectroscopy. [reprint (PDF)] |
| 18. | Room temperature neagtive differential resistance characteristics of polar III-nitride resonant tunneling diodes C. Bayram, Z. Vashaei, and M. Razeghi Applied Physics Letters, Vol. 97, No. 9, p. 092104-1-- August 30, 2010 ...[Visit Journal] III-nitride resonant tunneling diodes (RTDs), consisting Al0.2Ga0.8N/GaN double-barrier (DB) active layers, were grown on c-plane lateral epitaxial overgrowth (LEO) GaN/sapphire and c-plane freestanding (FS) GaN. RTDs on both templates, fabricated into mesa diameters ranging from 5 to 35 μm, showed negative differential resistance (NDR) at room temperature. NDR characteristics (voltage and current density at NDR onset and current-peak-to-valley ratio) were analyzed and reported as a function of device size and substrate choice. Our results show that LEO RTDs perform as well as FS ones and DB active layer design and quality have been the bottlenecks in III-nitride RTDs. [reprint (PDF)] |
| 18. | Determination of of Band Gap Energy of Al1-xInxN Grown by Metal Organic Chemical Vapor Deposition in the High Al Composition Regime K.S. Kim, A. Saxler, P. Kung, M. Razeghi, and K.Y. Lim Applied Physics Letters 71 (6)-- August 11, 1997 ...[Visit Journal] Ternary AlInN was grown by metal–organic chemical-vapor deposition in the high Al composition regime. The band-gap energy of AlInN ternary was measured by optical absorption spectroscopy at room temperature. The band-gap energy of Al0.92In0.08N is 5.26 eV. The potential application of AlInN as a barrier material for GaN is also discussed. [reprint (PDF)] |
| 18. | High power asymmetrical InAsSb/InAsSbP/AlAsSb double heterostructure lasers emitting at 3.4 μm D. Wu, B. Lane, H. Mohseni, J. Diaz and M. Razeghi Applied Physics Letters 74 (9)-- March 1, 1999 ...[Visit Journal] Midinfrared lasers with an asymmetrical InPAsSb/InAsSb/AlAsSb double heterostructure are reported. Using the asymmetrical double heterostructure, p- and n-cladding layers are separately optimized; high energy-gap AlAsSb (Eg ≈ 1.5 eV) for the p-type cladding layer to reduce the leakage current, and thus to increase To, and low energy-gap InPAsSb (Eg ≈ 0.5 eV) for the n-cladding layer to have low turn-on voltage. 100-μm-width broad-area lasers with 1000 μm cavity length exhibited peak output powers of 1.88 W in pulse and 350 mW in continuous wave modes per two facets at T=80 K with To of 54 K and turn-on voltage of 0.36 V. Maximum peak output powers up to 6.7 W were obtained from a laser bar of total aperture of 400 μm width and cavity length of 1000 μm, with a differential efficiency of 34% and far-field beam divergence narrower than 40° at 80 K. [reprint (PDF)] |
| 18. | High speed type-II superlattice based photodetectors transferred on sapphire Arash Dehzangi, Ryan McClintock, Donghai Wu, Jiakai Li, Stephen Johnson, Emily Dial and Manijeh Razeghi Applied Physics Express, Volume 12, Number 11-- October 3, 2019 ...[Visit Journal] We report the substrate transfer of InAs/GaSb/AlSb based type-II superlattice (T2SL) e-SWIR photodetector from native GaSb substrates to low loss sapphire substrate in order to enhance the frequency response of the device. We have demonstrated the damage-free transfer of T2SL-based thin-films to sapphire substrate using top–down processing and a chemical epilayer release technique. After transfer the −3 dB cut-off frequency increased from 6.4 GHz to 17.2 GHz, for 8 μm diameter circular mesas under -15 V applied bias. We also investigated the cut-off frequency verses applied bias and lateral scaling to assess the limitations for even higher frequency performance. Direct Link [reprint (PDF)] |
| 18. | Persistent photoconductivity in Ga0.49In0.51P/GaAs heterojunctions S. Ben Amor; L. Dmowski; J. C. Portal; N. J. Pulsford; R. J. Nicholas; J. Singleton; M. Razeghi J. Appl. Phys. 65, 2756–2760 (1989-- November 18, 1988 ...[Visit Journal] We have studied the persistent photoconductivity (PPC) effect in Ga0.49 Ino.
sl P IGaAs
heterostructures. Through time- and temperature-dependent Hall effect, we observe very small
relaxation rates and the PPC remains observable at room temperature. Optical experiments
show an optical energy threshold of 1.15 e V and an infrared quenching of the ppc. Thermal
cycling of the samples strongly affects the PPC and the quenching temperature. The center
responsible for the observed PPC, therefore, appears related to defects, Most of our
observations are qualitatively understood in a large lattice relaxation DX-like center approach.
However, the origin of the high quenching temperature remains to be explained. [reprint (PDF)] |
| 18. | Room temperature quantum cascade lasers with 27% wall plug efficiency Y. Bai, N. Bandyopadhyay, S. Tsao, S. Slivken and M. Razeghi Applied Physics Letters, Vol. 98, No. 18, p. 181102-1-- May 3, 2011 ...[Visit Journal] Using the recently proposed shallow-well design, we demonstrate InP based quantum cascade lasers (QCLs) emitting around 4.9 μm with 27% and 21% wall plug efficiencies in room temperature (298 K) pulsed and continuous wave (CW) operations, respectively. The laser core consists of 40 QCL-stages. The highest cw efficiency is obtained from a buried-ridge device with a ridge width of 8 μm and a cavity length of 5 mm. The front and back facets are antireflection and high-reflection coated, respectively. The maximum single facet cw power at room temperature amounts to 5.1 W. [reprint (PDF)] |
| 18. | Low threshold GaInAsP/InP lasers with good temperature dependence grown by low pressure MOVPE J.-P. Hirtz, M. Razeghi, J.-P. Larivain, S. Hersee, J.-P. Duchemin Electronics Letters Volume 17, Issue 3 https://doi.org/10.1049/el:19810081-- February 1, 1981 ...[Visit Journal] Room temperature pulsed operation has been achieved in the 1.2–1.3 μm region for GaInAsP/InP lasers grown by low pressure metalorganic vapour phase epitaxy. Thresholds as low as 1.2 kA/cm2 and threshold temperature dependences of exp T/T0, with T0 up to 80 K, have been obtained. [reprint (PDF)] |
| 18. | Solar-blind photodetectors and focal plane arrays based on AlGaN R. McClintock, M. Razeghi Proc. SPIE 9555, Optical Sensing, Imaging, and Photon Counting: Nanostructured Devices and Applications, 955502-- August 25, 2015 ...[Visit Journal] III-Nitride material system (AlGaInN) possesses unique optical, electrical and structural properties such as a wide tunable direct bandgap, inherent fast carrier dynamics; good carrier transport properties, high breakdown fields; and high robustness and chemical stability. Recent technological advances in the wide bandgap AlGaN portion of this material system have led to a renewed interest in ultraviolet (UV) photodetectors. These detectors find use in numerous applications in the defense, commercial and scientific arenas such as covert space-to-space communications, early missile threat detection, chemical and biological threat detection and spectroscopy, flame detection and monitoring, UV environmental monitoring, and UV astronomy.1,2,3 Back illuminated detectors operating in the solar blind region are of special interest. Back illumination allows the detector to be hybridized to a silicon read-out integrated circuit, epi-side down, and still collect light through the back of the transparent sapphire substrate. This allows the realization of solar blind focal plane arrays (FPAs) for imaging applications. Solar-blind FPAs are especially important because of the near total absence of any background radiation in this region.
In this talk, we will present our recent back-illuminated solar-blind photodetector, mini-array, and FPA results. By systematically optimizing the design of the structure we have realized external quantum efficiencies (EQE) of in excess of 89% for pixel-sized detectors. Based on the absence of any anti-reflection coating, this corresponds to nearly 100% internal quantum efficiency. At the same time, the dark current remains below ~2 × 10-9 A/cm² even at 10 volts of reverse bias. The detector has a very sharp falloff starting at 275 with the UV-solar rejection of better than three orders of magnitude, and a visible rejection ratio is more than 6 orders of magnitude. This high performance photodetector design was then used as the basis of the realization of solar-blind FPA. We demonstrated a 320×256 FPA with a peak detection wavelength of 278nm. The operability of the FPA was better than 92%, and excellent corrected imaging was obtained. [reprint (PDF)] |
| 18. | Multi-color 4–20 μm In-P-based Quantum Well Infrared Photodetectors C. Jelen, S. Slivken, G.J. Brown, and M. Razeghi SPIE Conference, San Jose, CA, -- January 27, 1999 ...[Visit Journal] In order to tune the wavelength of lattice-matched QWIP detectors over the range from 4 - 20 &mum, new designs are demonstrated for the first time which combine InGaAlAs and InGaAsP layers lattice-matched to InP and grown by gas-source molecular beam epitaxy. We demonstrate the first long-wavelength quantum well infrared photodetectors using the lattice-matched n-doped InGaAlAs/InP materials system. Samples with AlAs mole fractions of 0.0, 0.1, and 0.15 result in cutoff wavelengths of 8.5, 13.3, and 19.4 μm, respectively. A 45 degree facet coupled illumination responsivity of R equals 0.37 A/W and detectivity of D*(λ) equals 1x109 cm·Hz½·W-1 at T = 77 K, for a cutoff wavelength λc equals 13.3 μm have been achieved. Based on the measured intersubband photoresponse wavelength, a null conduction band offset is expected for In0.52Ga0.21Al0.27As/InP heterojunctions. We also report quantum well infrared photodetector structures of In0.53Ga0.47As/Al0.48In0.52As grown on InP substrate with photoresponse at 4 μm suitable for mid-wavelength infrared detectors. These detectors exhibit a constant peak responsivity of 30 mA/W independent of temperature in the range from T equals 77 K to T equals 200 K. Combining these two materials, we report the first multispectral detectors that combine lattice-matched quantum wells of InGaAs/InAlAs and InGaAs/InP. Utilizing two contacts, a voltage tunable detector with (lambda) p equals 8 micrometer at a bias of V equals 5 V and λp equals 4 μm at V equals 10 V is demonstrated. [reprint (PDF)] |
| 18. | Substrate removal for high quantum efficiency back side illuminated type-II InAs/GaSb photodetectors P.Y. Delaunay, B.M. Nguyen, D. Hoffman and M. Razeghi Applied Physics Letters, Vol. 91, No. 23, p. 231106-- December 3, 2007 ...[Visit Journal] A substrate removal technique using an InAsSb etch stop layer improves by a factor of 2 the quantum efficiency of back side illuminated type-II InAs/GaSb superlattice photodetectors. After etching of the GaSb substrate with a CrO3 based solution, the quantum efficiency of the diodes presents Fabry-Pérot oscillations averaging at 56%. Due to the confinement of the infrared light inside the devices, the quantum efficiency for certain devices reaches 75% at 8.5 µm. The implementation of this new technique to a focal plane array resulted in a decrease of the integration time from 0.23 to 0.08 ms. [reprint (PDF)] |
| 18. | Optical losses of Al-free lasers for λ = 0.808 and 0.98 μm H. Yi, J. Diaz, B. Lane, and M. Razeghi Applied Physics Letters 69 (20)-- November 11, 1996 ...[Visit Journal] In this work, we study the origin of the optical losses in Al‐free InGaAsP/GaAs (λ=0.808 μm) and InGaAs/GaAs/InGaP (λ=0.980 μm) lasers. Theoretical modeling and the experimental results indicate that the scattering of the laser beam by refractive index fluctuation in the alloys is the dominant loss in our lasers, and the loss due to the free‐carrier absorption and scattering by interface roughness are negligible. [reprint (PDF)] |
| 18. | First GaInAsP‐InP double‐heterostructure laser emitting at 1.27 μm on a silicon substrate M. Razeghi; M. Defour; F. Omnes; Ph. Maurel; J. Chazelas; F. Brillouet Appl. Phys. Lett. 53, 725–727 (1988)-- June 21, 1988 ...[Visit Journal] We report the first successful room-temperature GalnAsP-InP double-heterostructure laser
emitting at 1.27 pm, grown by low-pressure metalorganic chemical vapor deposition on a Si
substrate. A pulsed threshold current density of 10 kAlcm2 at room temperature with an
external quantum efficiency of 10% per facet and an output power of20 mW (for an oxidedefined stripe geometry with 12 pm stripe width and 250 pm cavity length) has been
measured. The first aging test in pulse operation shows an increase of threshold current of only
7% for a cumulative time of 80 s at room temperature. [reprint (PDF)] |
| 18. | Recent advances in high performance antimonide-based superlattice FPAs E.K. Huang, B.M. Nguyen, S.R. Darvish, S. Abdollahi Pour, G. Chen, A. Haddadi, and M.A. Hoang SPIE Proceedings, Infrared technology and Applications XXXVII, Orlando, FL, Vol. 8012, p. 80120T-1-- April 25, 2011 ...[Visit Journal] Infrared detection technologies entering the third generation demand performances for higher detectivity, higher operating temperature, higher resolution and multi-color detection, all accomplished with better yield and lower manufacturing/operating costs. Type-II antimonide based superlattices (T2SL) are making firm steps toward the new era of focal plane array imaging as witnessed in the unique advantages and significant progress achieved in recent years. In this talk, we will present the four research themes towards third generation imagers based on T2SL at the Center for Quantum Devices. High performance LWIR megapixel focal plane arrays (FPAs) are demonstrated at 80K with an NEDT of 23.6 mK using f/2 optics, an integration time of 0.13 ms and a 300 K background. MWIR and LWIR FPAs on non-native GaAs substrates are demonstrated as a proof of concept for the cost reduction and mass production of this technology. In the MWIR regime, progress has been made to elevate the operating temperature of the device, in order to avoid the burden of liquid nitrogen cooling. We have demonstrated a quantum efficiency above 50%, and a specific detectivity of 1.05x1012 cm·Hz1/2/W at 150 K for 4.2 μm cut-off single element devices. Progress on LWIR/LWIR dual color FPAs as well as novel approaches for FPA fabrication will also be discussed. [reprint (PDF)] |
| 18. | Very high quantum efficiency in type-II InAs/GaSb superlattice photodiode with cutoff of 12 µm B.M. Nguyen, D. Hoffman, Y. Wei, P.Y. Delaunay, A. Hood and M. Razeghi Applied Physics Letters, Vol. 90, No. 23, p. 231108-1-- June 4, 2007 ...[Visit Journal] The authors report the dependence of the quantum efficiency on device thickness of Type-II InAs/GaSb superlattice photodetectors with a cutoff wavelength around 12 µm. The quantum efficiency and responsivity show a clear delineation in comparison to the device thickness. An external single-pass quantum efficiency of 54% is obtained for a 12 µm cutoff wavelength photodiodes with a -region thickness of 6.0 µm. The R0A value is kept stable for the range of structure thicknesses allowing for a specific detectivity (2.2×1011 cm·Hz½/W). [reprint (PDF)] |
| 18. | High-detectivity quantum-dot infrared photodetectors grown by metal-organic chemical-vapor deposition J. Szafraniec, S. Tsao, W. Zhang, H. Lim, M. Taguchi, A.A. Quivy, B. Movaghar and M. Razeghi Applied Physics Letters 88 (121102)-- March 20, 2006 ...[Visit Journal] A mid-wavelength infrared photodetector based on InGaAs quantum dots buried in an InGaP matrix
and deposited on a GaAs substrate was demonstrated. Its photoresponse at T=77 K was measured
to be around 4.7 μm with a cutoff at 5.5 μm. Due to the high peak responsivity of 1.2 A/W and low
dark-current noise of the device, a specific peak detectivity of 1.1 x 1012 cm·Hz½·W−1 was
achieved at −0.9 V bias [reprint (PDF)] |
| 17. | The effect of doping the M-barrier in very long-wave type-II InAs/GaSb heterodiodes D. Hoffman, B.M. Nguyen, E.K. Huang, P.Y. Delaunay, M. Razeghi, M.Z. Tidrow and J. Pellegrino Applied Physics Letters, Vol. 93, No. 3, p. 031107-1-- July 21, 2008 ...[Visit Journal] A variation on the standard homo-diode Type-II superlattice with an M-barrier between the pi-region and the n-region is shown to suppress the dark currents. By determining the optimal doping level of the M-superlattice, dark current densities of 4.95 mA·cm-2 and quantum efficiencies in excess of 20% have been demonstrated at the moderate reverse bias of 50 mV; allowing for near background-limited performance with a Johnson-noise detectivity of 3.11×1010 Jones at 77 K for a 14.58 µm cutoff wavelength for large area diodes without passivation. This is comparable to values for the state-of-the-art HgCdTe photodiodes. [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-xSbx 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 Thermal Stability of κ-Ga2O3 Grown by MOCVD Junhee Lee, Honghyuk Kim, Lakshay Gautam and Manijeh Razeghi Lee, J.; Kim, H.; Gautam, L.; Razeghi, M. High Thermal Stability of κ-Ga2O3 Grown by MOCVD. Crystals 2021, 11, 446. https://doi.org/ 10.3390/cryst11040446 ...[Visit Journal] We report a high thermal stability of kappa gallium oxide grown on c-plane sapphire substrate by metal organic chemical vapor deposition. Kappa gallium oxide is widely known as a metastable polymorph transitioning its phase when subjected to a high temperature. Here, we show the kappa gallium oxide whose phase is stable in a high temperature annealing process at 1000 °C. These oxide films were grown at 690 °C under nitrogen carrier gas. The materials showed high electrical resistivity when doped with silicon, whereas the film conductivity was significantly improved when doped with both indium and silicon. This work provides a pathway to overcoming limitations for the advance in utilizing kappa gallium oxide possessing superior electrical characteristics. [reprint (PDF)] |
| 17. | Optical and crystallographic properties and impurity incorporation of GaxIn1−xAs grown by liquid phase epitaxy, vapor phase epitaxy, and metal organic chemical vapor deposition K.‐H. Goetz; D. Bimberg; H. Jürgensen; J. Selders; A. V. Solomonov; G. F. Glinskii; M. Razeghi J. Appl. Phys. 54 (8): 4543–4552 (1983)-- March 29, 1983 ...[Visit Journal] Optical, crystallographic, and transport properties of nominally undoped n‐type and Zn doped p‐type Gax In1−xAs /InP (0.44 [reprint (PDF)] |
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