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3.  InAs/InAs1-xSbx type-II superlattices for high performance long wavelength infrared detection
M. Razeghi, A. Haddadi, A. M. Hoang, R. Chevallier, S. Adhikary, A. Dehzangi
Proc. SPIE 9819, Infrared Technology and Applications XLII, 981909-- May 20, 2016 ...[Visit Journal]
We report InAs/InAs1-xSbx type-II superlattice base photodetector as high performance long-wavelength infrared nBn device grown on GaSb substrate. The device has 6 μm-thick absorption region, and shows optical performance with a peak responsivity of 4.47 A/W at 7.9 μm, which is corresponding to the quantum efficiency of 54% at a bias voltage of negative 90 mV, where no anti-reflection coating was used for front-side illumination. At 77K, the photodetector’s 50% cut-off wavelength was ~10 μm. The device shows the detectivity of 2.8x1011 cm•Hz½/W at 77 K, where RxA and dark current density were 119 Ω•cm² and 4.4x10-4 A/cm² , respectively, under -90 mV applied bias voltage [reprint (PDF)]
 
3.  Background limited long wavelength infrared type-II InAs/GaSb superlattice photodiodes operating at 110 K
B.M. Nguyen, D. Hoffman, E.K. Huang, P.Y. Delaunay, and M. Razeghi
Applied Physics Letters, Vol. 93, No. 12, p. 123502-1-- September 22, 2008 ...[Visit Journal]
The utilization of the P+-pi-M-N+ photodiode architecture in conjunction with a thick active region can significantly improve long wavelength infrared Type-II InAs/GaSb superlattice photodiodes. By studying the effect of the depletion region placement on the quantum efficiency in a thick structure, we achieved a topside illuminated quantum efficiency of 50% for an N-on-P diode at 8.0 µm at 77 K. Both the double heterostructure design and the application of polyimide passivation greatly reduce the surface leakage, giving an R0A of 416 Ω·cm2 for a 1% cutoff wavelength of 10.52 µm, a Shot–Johnson detectivity of 8.1×1011 cm·Hz½/W at 77 K, and a background limited operating temperature of 110 K with 300 K background. [reprint (PDF)]
 
3.  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)]
 
3.  Surface leakage current reduction in long wavelength infrared type-II InAs/GaSb superlattice photodiodes
S. Bogdanov, B.M. Nguyen, A.M. Hoang, and M. Razeghi
Applied Physics Letters, Vol. 98, No. 18, p. 183501-1-- May 2, 2011 ...[Visit Journal]
Dielectric passivation of long wavelength infrared Type-II InAs/GaSb superlattice photodetectors with different active region doping profiles has been studied. SiO2 passivation was shown to be efficient as long as it was not put in direct contact with the highly doped superlattice. A hybrid graded doping profile combined with the shallow etch technique reduced the surface leakage current in SiO2 passivated devices by up to two orders of magnitude compared to the usual design. As a result, at 77 K the SiO(2) passivated devices with 10.5 μm cutoff wavelength exhibit an R0A of 120 Ω·cm², RmaxA of 6000 Ω·cm², and a dark current level of 3.5×10−5 A·cm−2 at −50 mV bias. [reprint (PDF)]
 
3.  High-power, continuous-wave, phase-locked quantum cascade laser arrays emitting at 8 μm
WENJIA ZHOU,QUAN-YONG LU,DONG-HAI WU, STEVEN SLIVKEN, AND MANIJEH RAZEGHI
OPTICS EXPRESS 27, 15776-15785-- May 20, 2019 ...[Visit Journal]
We report a room-temperature eight-element phase-locked quantum cascade laser array emitting at 8 μm with a high continuous-wave power of 8.2 W and wall plug efficiency of 9.5%. The laser array operates primarily via the in-phase supermode and has single-mode emission with a side-mode suppression ratio of ~20 dB. The quantum cascade laser active region is based on a high differential gain (8.7 cm/kA) and low voltage defect (90 meV) design. A record high wall plug efficiency of 20.4% is achieved from a low loss buried ridge type single-element Fabry-Perot laser operating in pulsed mode at 20 °C. [reprint (PDF)]
 
3.  High operability 1024 x 1024 long wavelength infrared focal plane array base on Type-II InAs/GaSb superlattice
A. Haddadi, S.R. Darvish, G. Chen, A.M. Hoang, B.M. Nguyen and M. Razeghi
AIP Conference Proceedings, Vol. 1416, p. 56-58_NGS15 Conf_Blacksburg, VA_Aug 1-5, 2011-- December 31, 2011 ...[Visit Journal]
Fabrication and characterization of a high performance 1024×1024 long wavelength infrared type‐II superlattice focal plane array are described. The FPA performs imaging at a continous rate of 15.00 frames/sec. Each pixel has pitch of 18μm with a fill factor of 71.31%. It demonstrates excellent operability of 95.8% and 97.4% at 81 and 68K operation temperature. The external quantum efficiency is ∼81% without any antireflective coating. Using F∕2 optics and an integration time of 0.13ms, the FPA exhibits an NEDT as low as 27 and 19mK at operating temperatures of 81 and 68K respectively. [reprint (PDF)]
 
3.  Mid-infrared quantum cascade lasers with high wall plug efficiency
Y. Bai, B. Gokden, S. Slivken, S.R. Darvish, S.A. Pour, and M. Razeghi
SPIE Proceedings, San Jose, CA Volume 7222-0O-- January 26, 2009 ...[Visit Journal]
We demonstrate optimization of continuous wave (cw) operation of 4.6 µm quantum cascade lasers (QCLs). A 19.7 µm by 5 mm, double channel processed device exhibits 33% cw WPE at 80 K. Room temperature cw WPE as high as 12.5% is obtained from a 10.6 µm by 4.8 mm device, epilayer-down bonded on a diamond submount. With the semi-insulating regrowth in a buried ridge geometry, 15% WPE is obtained with 2.8 W total output power in cw mode at room temperature. This accomplishment is achieved by systematically decreasing the parasitic voltage drop, reducing the waveguide loss and improving the thermal management. [reprint (PDF)]
 
3.  Antimonite-based gap-engineered type-II superlattice materials grown by MBE and MOCVD for the third generation of infrared imagers
Manijeh Razeghi, Arash Dehzangi, Donghai Wu, Ryan McClintock, Yiyun Zhang, Quentin Durlin, Jiakai Li, Fanfei Meng
Proc. SPIE Defense + Commercial Sensing,Infrared Technology and Applications XLV, 110020G -- May 7, 2019 ...[Visit Journal]
Third generation of infrared imagers demand performances for higher detectivity, higher operating temperature, higher resolution, and multi-color detection all accomplished with better yield and lower manufacturing costs. Antimonidebased gap-engineered Type-II superlattices (T2SLs) material system is considered as a potential alternative for MercuryCadmium-Telluride (HgCdTe) technology in all different infrared detection regimes from short to very long wavelengths for the third generation of infrared imagers. This is due to the incredible growth in the understanding of its material properties and improvement of device processing which leads to design and fabrication of better devices. We will present the most recent research results on Antimonide-based gap-engineered Type-II superlattices, such as highperformance dual-band SWIR/MWIR photo-detectors and focal plane arrays for different infrared regimes, toward the third generation of infrared imaging systems at the Center for Zuantum Devices. Comparing metal-organic chemical vapor deposition (MOCVD), vs molecular beam epitaxy (MBE). [reprint (PDF)]
 
2.  Low frequency noise in 1024 x 1024 long wavelength infrared focal plane array base on Type-II InAs/GaSb superlattice
A. Haddadi, S.R. Darvish, G. Chen, A.M. Hoang, B.M. Nguyen and M. Razeghi
SPIE Proceedings, Vol. 8268, p. 82680X-- January 22, 2012 ...[Visit Journal]
Recently, the type-II InAs/GaSb superlattice (T2SL) material platform is considered as a potential alternative for HgCdTe technology in long wavelength infrared (LWIR) imaging. This is due to the incredible growth in the understanding of its material properties and improvement of device processing which leads to design and fabrication of better devices. In this paper, we report electrical low frequency noise measurement on a high performance type-II InAs/GaSb superlattice 1024×1024 LWIR focal plane array. [reprint (PDF)]
 
2.  High-power high-wall plug efficiency mid-infrared quantum cascade lasers based on InP/GaInAs/InAlAs material system
M. Razeghi
SPIE Proceedings, San Jose, CA Volume 7230-11-- January 26, 2009 ...[Visit Journal]
The latest result at the Center for Quantum Devices about high power, high wall plug efficiency, mid-infrared quantum cascade lasers (QCLs) is presented. At an emitting wavelength of 4.8 µm, an output power of 3.4 W and a wall plug efficiency of 16.5% are demonstrated from a single device operating in continuous wave at room temperature. At a longer wavelength of 10.2 µm, average power as high as 2.2 W is demonstrated at room temperature. Gas-source molecular beam epitaxy is used to grow the QCL core in an InP/GaInAs/InAlAs material system. Fe-doped semiinsulating regrowth is performed by metal organic chemical vapor deposition for efficient heat removal and low waveguide loss. This accomplishment marks an important milestone in the development of high performance midinfrared QCLs. [reprint (PDF)]
 
2.  Growth of AlGaN on silicon substrates: a novel way to make back-illuminated ultraviolet photodetectors
Ryan McClintock ; Manijeh Razeghi
Proc. SPIE 9555, Optical Sensing, Imaging, and Photon Counting: Nanostructured Devices and Applications, 95550U-- August 28, 2015 ...[Visit Journal]
AlGaN, with its tunable wide-bandgap is a good choice for the realization of ultraviolet photodetectors. AlGaN films tend to be grown on foreign substrates such as sapphire, which is the most common choice for back-illuminated devices. However, even ultraviolet opaque substrates like silicon holds promise because, silicon can be removed by chemical treatment to allow back-illumination,1 and it is a very low-cost substrate which is available in large diameters up to 300 mm. However, Implementation of silicon as the solar-blind PD substrates requires overcoming the lattice-mismatch (17%) with the AlxGa1-xN that leads to high density of dislocation and crack-initiating stress. In this talk, we report the growth of thick crack-free AlGaN films on (111) silicon substrates through the use of a substrate patterning and mask-less selective area regrowth. This technique is critical as it decouples the epilayers and the substrate and allows for crack-free growth; however, the masking also helps to reduce the dislocation density by inclining the growth direction and encouraging dislocations to annihilate. A back-illuminated p-i-n PD structure is subsequently grown on this high quality template layer. After processing and hybridizing the device we use a chemical process to selectively remove the silicon substrate. This removal has minimal effect on the device, but it removes the UV-opaque silicon and allows back-illumination of the photodetector. We report our latest results of back-illuminated solar-blind photodetectors growth on silicon. [reprint (PDF)]
 
2.  Transport properties in n-type InSb films grown by metalorganic chemical vapor deposition
S.N. Song, J.B. Ketterson, Y.H. Choi, R. Sudharsanan, and M. Razeghi
Applied Physics Letters 63 (7)-- August 16, 1993 ...[Visit Journal]
We have measured the temperature and magnetic field dependence of the Hall mobility and transverse magnetoresistance in n-type InSb films epitaxially grown on GaAs substrates by metalorganic chemical vapor deposition. The films show a giant magnetoresistance: e.g., at 240 K the resistivity increases over 20 times at a magnetic field of 5 T; the low field coefficient of resistivity at 77 K is as high as 47.5 μ·Ω· cm/G. The Hall mobility decreases with magnetic field and saturates at higher fields. By taking the interface carrier transport into account, the observed field dependence of the Hall mobility and magnetoresistance may be understood based on a two-layer model. [reprint (PDF)]
 
2.  Type-II InAs/GaSb/AlSb superlatticebased heterojunction phototransistors: back to the future
Abbas Haddadi, Arash Dehzangi, Romain Chevallier, Thomas Yang, Manijeh Razeghi
Proc. SPIE 10540, Quantum Sensing and Nano Electronics and Photonics XV- Page-1054004-1-- January 26, 2018 ...[Visit Journal]
Most of reported HPTs in literatures are based on InGaAs compounds that cover NIR spectral region. However, InGaAs compounds provide limited cut-off wavelength tunability. In contrast, type-II superlattices (T2SLs) are a developing new material system with intrinsic advantages such as great flexibility in bandgap engineering, low growth and manufacturing cost, high-uniformity, auger recombination suppression, and high carrier effective mass that are becoming an attractive candidate for infrared detection and imaging from short-wavelength infrared to very long wavelength infrared regime. We present the recent advancements in T2SL-based heterojunction phototransistors in e– SWIR, MWIR and LWIR spectral ranges. A mid-wavelength infrared heterojunction phototransistor based on type-II InAs/AlSb/GaSb superlattices on GaSb substrate has been demonstrated. Then, we present the effect of vertical scaling on the optical and electrical performance of heterojunction phototransistors, where the performance of devices with different base width was compared as the base was scaled from 60 down to 40 nm. [reprint (PDF)]
 
2.  Surface plasmon enhanced light emission from AlGaN-based ultraviolet light-emitting diodes grown on Si (111)
Chu-Young Cho, Yinjun Zhang, Erdem Cicek, Benjamin Rahnema, Yanbo Bai, Ryan McClintock, and Manijeh Razeghi
Appl. Phys. Lett. 102, 211110 (2013)-- May 31, 2013 ...[Visit Journal]
We report on the development of surface plasmon (SP) enhanced AlGaN-based multiple quantum wells (MQWs) ultraviolet (UV) light-emitting diodes (LEDs) grown on silicon (111) substrates. In order to generate SP-coupling with the radiating dipoles in MQWs, an aluminum layer is selectively deposited in holes etched in the top p-AlGaN to p-GaN layers. After flip-chip bonding and substrate removal, an optical output power of ∼1.2 mW is achieved at an emission wavelength of 346 nm; the output power of these UV LEDs with Al layer is increased by 45% compared to that of conventional UV LEDs without Al layer. This enhancement can be attributed to an increase in the spontaneous emission rate and improved internal quantum efficiency via resonance coupling between excitons in MQWs and SPs in the aluminum layer. [reprint (PDF)]
 
2.  Investigation of impurities in type-II InAs/GaSb superlattices via capacitance-voltage measurement
G. Chen, A. M. Hoang, S. Bogdanov, A. Haddadi, P. R. Bijjam, B.-M. Nguyen, and M. Razeghi
Applied Physics Letters 103, 033512 (2013)-- July 17, 2013 ...[Visit Journal]
Capacitance-voltage measurement was utilized to characterize impurities in the non-intentionally doped region of Type-II InAs/GaSb superlattice p-i-n photodiodes. Ionized carrier concentration versus temperature dependence revealed the presence of a kind of defects with activation energy below 6 meV and a total concentration of low 1015 cm−3. Correlation between defect characteristics and superlattice designs was studied. The defects exhibited a p-type behavior with decreasing activation energy as the InAs thickness increased from 7 to 11 monolayers, while maintaining the GaSb thickness of 7 monolayers. With 13 monolayers of InAs, the superlattice became n-type and the activation energy deviated from the p-type trend. [reprint (PDF)]
 
2.  Photoluminescence Study of AlGaN-based 280 nm Ultraviolet Light-Emitting Diodes
A. Yasan, R. McClintock, K. Mayes, D.H. Kim, P. Kung, and M. Razeghi
Applied Physics Letters, 83 (20)-- November 17, 2003 ...[Visit Journal]
We investigated optical properties of single quantum well AlGaN-based UV 280 nm light-emitting diodes using temperature-dependent photoluminescence (PL) measurement. We found an "S-shaped" temperature dependence of the peak energy. From the Arrhenius plot of integrated PL intensity, we speculate that dislocations as well as thermal emission of carriers out of the quantum well are responsible for the PL quenching behavior. Also a second nonradiative channel with much lower activation energy was found, the origin of which we believe to be quenching of the bound excitons [reprint (PDF)]
 
2.  High performance antimony based type-II superlattice photodiodes on GaAs substrates
B.M. Nguyen, D. Hoffman, E.K. Huang, P.Y. Delaunay, and M. Razeghi
SPIE Porceedings, Vol. 7298, Orlando, FL 2009, p. 72981T-- April 13, 2009 ...[Visit Journal]
In recent years, Type-II InAs/GaSb superlattices grown on GaSb substrate have achieved significant advances in both structural design and material growth, making Type-II superlattice infrared detector a rival competitor to the state-of-the-art MCT technology. However, the limited size and strong infrared absorption of GaSb substrates prevent large format type-II superlattice infrared imagers from being realized. In this work, we demonstrate type-II superlattices grown on GaAs substrates, which is a significant step toward third generation infrared imaging at low cost. The device performances of Type-II superalttice photodetectors grown on these two substrates are compared. [reprint (PDF)]
 
2.  Growth and characterization of InAs/GaSb Type-II superlattices for long-wavelength infrared detectors
H. Mohseni, E. Michel, M. Razeghi, W. Mitchel, and G. Brown
SPIE Conference, San Jose, CA, -- January 28, 1998 ...[Visit Journal]
We report the molecular beam epitaxial growth and characterization of InAs/GaSb superlattices grown on semi- insulating GaAs substrate for long wavelength IR detectors. Photoconductive detectors fabricated from the superlattices showed 80% cut-off at 11.6 μm and peak responsivity of 6.5 V/W with Johnson noise limited detectivity of 2.36 x 109 cm·Hz½/W at 10.7 μm at 78 K. The responsivity decreases at higher temperatures with a T-2 behavior rather than exponential decay, and at room temperature the responsivity is about 660 mV/W at 11 μm. Lower Auger recombination rate in this system provides comparable detectivity to the best HgCdTe detectors at 300K. Higher uniformity over large areas, simpler growth and the possibility of having read-out circuits in the same GaAs chip are the advantages of this system over HgCdTe detectors for near room temperature operation. [reprint (PDF)]
 
2.  Low irradiance background limited type-II superlattice MWIR M-barrier imager
E.K. Huang, S. Abdollahi Pour, M.A. Hoang, A. Haddadi, M. Razeghi and M.Z. Tidrow
OSA Optics Letters (OL), Vol. 37, No. 11, p. 2025-2027-- June 1, 2012 ...[Visit Journal]
We report a type-II superlattice mid-wave infrared 320 × 256 imager at 81 K with the M-barrier design that achieved background limited performance (BLIP) and ∼99%operability. The 280 K blackbody’s photon irradiance was limited by an aperture and a band-pass filter from 3.6 μm to 3.8 μm resulting in a total flux of ∼5 × 1012 ph·cm−2·s−1. Under these low-light conditions, and consequently the use of a 13.5 ms integration time, the imager was observed to be BLIP thanks to a ∼5 pA dark current from the 27 μm wide pixels. The total noise was dominated by the photon flux and read-out circuit which gave the imager a noise equivalent input of ∼5 × 1010 ph·cm−2·s−1 and temperature sensitivity of 9 mK with F∕2.3 optics. Excellent imagery obtained using a 1-point correction alludes to the array’s uniform responsivity. [reprint (PDF)]
 
2.  III-Nitride Avalanche Photodiodes
P. Kung, R. McClintock, J. Pau Vizcaino, K. Minder, C. Bayram and M. Razeghi
SPIE Conference, January 25-29, 2007, San Jose, CA Proceedings – Quantum Sensing and Nanophotonic Devices IV, Vol. 6479, p. 64791J-1-12-- January 29, 2007 ...[Visit Journal]
Wide bandgap III-Nitride semiconductors are a promising material system for the development of ultraviolet avalanche photodiodes (APDs) that could be a viable alternative to photomultiplier tubes. In this paper, we report the epitaxial growth and physical properties of device quality GaN layers on high quality AlN templates for the first backilluminated GaN p-i-n APD structures on transparent sapphire substrates. Under low bias and linear mode avalanche operation where they exhibited gains near 1500 after undergoing avalanche breakdown. The breakdown electric field in GaN was determined to be 2.73 MV/cm. The hole impact ionization coefficients were shown to be greater than those of electrons. [reprint (PDF)]
 
2.  Effects of substrate quality and orientation on the characteristics of III-nitride resonant tunneling diodes
Z. Vashaei, C. Bayram, R. McClintock and M. Razeghi
SPIE Proceedings, San Francisco, CA (January 22-27, 2011), Vol 7945, p. 79451A-- January 23, 2011 ...[Visit Journal]
Al(Ga)N/GaN resonant tunneling diodes (RTDs) are grown by metal-organic chemical vapor deposition. The effects of material quality on room temperature negative differential resistance (NDR) behaviour of RTDs are investigated by growing the RTD structure on AlN, GaN, and lateral epitaxial overgrowth GaN templates. This reveals that NDR characteristics of RTDs are very sensitive to material quality (such as surface roughness and dislocations density). The effects of the aluminum content of AlGaN double barriers (DB) and polarization fields on NDR characteristic of AlGaN/GaN RTDs were also investigated by employing low dislocation density c-plane (polar) and m-plane (nonpolar) freestanding GaN substrates. Lower aluminum content in the DB RTD active layer and minimization of dislocations and polarization fields enabled a more reliable and reproducible NDR behaviour at room temperature. [reprint (PDF)]
 
2.  High performance quantum cascade lasers (~11 μm) operating at high temperature (T>= 425K)
A. Tahraoui, A. Matlis, S. Slivken, J. Diaz, and M. Razeghi
Applied Physics Letters 78 (4)-- January 22, 2001 ...[Visit Journal]
We report record-low threshold current density and high output power for λ ∼ 11 μm Al0.48In0.52As/Ga0.47In0.53As quantum cascade lasers operating up to 425 K. The threshold current density is 1.1, 3.83, and 7.08 kA/cm² at 80, 300, and 425 K, respectively, for 5 μs pulses at a 200 Hz repetition rate. The cavity length is 3 mm with a stripe width of 20 μm. The maximum peak output power per facet is 1 W at 80 K, 0.5 W at 300 K, and more than 75 mW at 425 K. The characteristic temperature of these lasers is 174 K between 80 and 300 K and 218 K in the range of 300–425 K. [reprint (PDF)]
 
2.  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)]
 
2.  Polarity inversion of Type-II InAs/GaSb superlattice photodiodes
B.M. Nguyen, D. Hoffman, P.Y. Delaunay, M. Razeghi and V. Nathan
Applied Physics Letters, Vol. 91, No. 10, p. 103503-1-- September 3, 2007 ...[Visit Journal]
The authors demonstrated the realization of p-on-n Type-II InAs/GaSb superlattice photodiodes. Growth condition for high quality InAsSb layer lattice matched to GaSb was established for the use of an effective n-contact layer. By studying the effect of various GaSb capping layer thicknesses on the optical and electrical performances, an optimized thickness of 160 nm was determined. In comparison to as grown n-on-p superlattice photodiodes, this inverted design of p on n has shown similar quality. Finally, by analyzing Fabry-Perot interference fringes in the front side illuminated spectral measurement, the refractive index of the superlattice was determined to be approximately 3.8. [reprint (PDF)]
 
2.  GaInAsP/InP 1.35 μm Double Heterostructure Laser Grown on Silicon Substrate by Metalorganic Chemical Vapor Deposition
K. Mobarhan, C. Jelen, E. Kolev, and M. Razeghi
Journal of Applied Physics 74 (1)-- July 1, 1993 ...[Visit Journal]
A 1.35 μm GaInAsP/InP double heterostructure laser has been grown on a Si substrate using low‐pressure metalorganic chemical vapor deposition. This was done without the use of a superlattice layer or a very thick InP buffer layer, which are used to prevent the dislocations from spreading into the active layer. Pulsed operation with output power of over 200 mW per facet was achieved at room temperature for broad area lasers with 20 μm width and 170 μm cavity length. The threshold current density of a 350 μm cavity length device was 9.8 kA/cm². The characteristic temperature was 66 K. [reprint (PDF)]
 

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