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801. | First room‐temperature cw operation of a GaInAsP/InP light‐emitting diode on a silicon substrate M. Razeghi; R. Blondeau; M. Defour; F. Omnes; P. Maurel; F. Brillouet Appl. Phys. Lett. 53, 854–855 (1988)-- July 4, 1988 We report in this letter the first successful fabrication of an InP-GalnAsP light-emitting diode,
emitting at 1.15 pm grown by low-pressure metalorganic chemical vapor deposition on a
silicon substrate. The device has been operated under continuous wave operation at room
temperature for 24 h (with an injection current of 200 rnA), and showed no degradation.
reprint |
802. | 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 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 |
803. | High‐quality GaAs/Ga0.49In0.51P superlattices grown on GaAs and silicon substrates by low‐pressure metalorganic chemical vapor deposition Available M. Razeghi; Ph. Maurel; F. Omnes; M. Defour; C. Boothroyd; W. M. Stobbs; M. Kelly J. Appl. Phys. 63, 4511–4514 (1988) -- May 1, 1988 We report the successful growth of Ga0.49 Iuo.5 ! P-GaAs superlattices on GaAs and Si
substrates by low-pressure metalorganic chemical vapor deposition. The high quality of the
structure grown on GaAs and silicon substrates has been evidenced by transmission electron
microscopy photographs, that show very sharp interfaces between GaAs wells and
Gao.49InO.51 P barriers, with perfect control of thicknesses and compositions. Classical Hall
measurements performed on the sample further demonstrated the presence of a twodimensional electron ga.<; with a mobility at T = 4 K , fL (4 K) = 50000 cm2
1V Is, and a carrier
concentration n _ (4 K) = 2,9 X 1011 em -2. GaAs/Gao.49 InO.
51 P superlattices have been used,
as well as buffer layer in order to grow GaAs on silicon substrates. Mirrorlike single-crystal
GaAs has thus been obtained. A GaInP IGaAs heterostructure with electron HaH mobility as
high as 6000 cm2
/V Is at 300 K and 80000 cm2
/V Is at 4 K has been grown, which is the
highest mobility that has yet been reported for these materials, reprint |
804. | Monolithic integrated photoreceiver for 1.3–1.55‐μm wavelengths: Association of a Schottky photodiode and a field‐effect transistor on GaInP‐GaInAs heteroepitaxy A. Hosseini Therani; D. Decoster; J. P. Vilcot; M. Razeghi J. Appl. Phys. 64, 2215–2218 (1988) -- March 24, 1988 We present a monolithic integrated circuit associating a Schottky photodiode and a field-effect
transistor which has been fabricated, for the first time, on G8.0.49 InO.51 P /GaO,47 Ino.53 As
strained heteroepitaxiaI material. Static, dynamic, and noise properties of the Schottky
photodiode, the field-effect transistor, and the integrated circuit have been investigated and are
reported. As an example, dynamic responsivity up to 50 A/W can be achieved at 1.3-pm
wavelength for the integrated photoreceiver. The performance of the device is discussed, taking
into account the integrated circuit design and the main characteristics of the material. reprint |
805. | MOCVD challenge for III-V semiconductor materials for photonic and electronic devices on alternative substrates M. Razeghi, M. Defour , F. Omnes, P. Maurel , E. Bigan , O. Acher, J. Nagle, F. Brillouet , J.C. Portal M. Razeghi, M. Defour, F. Omnes, P. Maurel, E. Bigan, O. Acher, J. Nagle, F. Brillouet, J.C. Portal, MOCVD challenge for III-V semiconductor materials for photonic and electronic devices on alternative substrates, Journal of Crystal Growth, Volume 93, Issues 1–4, 1988, Pages 776-781,-- January 1, 1988 High quality II[-V semiconductor heterojunctions, quantum wells and superlauices have been grown on lattice matched and
alternative substrates such as silicon for photonic and electronic devices, using low pressure metalorganic chemical vapor deposition
growth technique. reprint |
806. | Pressure dependence study of the effective mass in Ga0.47In0.53As/InP heterojunctions D. Gauthier , L. Dmowski, J.C. Portal D. Leadley, M.A. Hopkins , M.A. Brummell , R.J. Nicholas, M. Razeghi, P. Maurel D. Gauthier, L. Dmowski, J.C. Portal, D. Leadley, M.A. Hopkins, M.A. Brummell, R.J. Nicholas, M. Razeghi, P. Maurel, Pressure dependence study of the effective mass in Ga0.47In0.53As/InP heterojunctions, Superlattices and Microstructures, Volume 4, Issue 2, 1988, Pages 201-206-- August 17, 1987 A study of the effective mass in GaInAs/InP heterojunctions under hydrostatic pressure up to 15 kbars is presented. Earlier results have shown the importance of hydrostatic pressure effects on the band parameters of the heterojunction to explain the experimental decrease of the carrier concentration with pressure at the interface (1). Here magnetophonon resonance experiments are performed to work out the increase of mass with pressure in our samples. The effective mass at atmospheric pressure is deduced from high temperature cyclotron resonance experiments and then used to calculate the frequency of the phonon interacting with the 2D electron gas (wo). The value of wo is found to be dependent on the carrier concentration of the measured samples. The lowest value is found for the highest carrier concentration sample.
A band edge effective mass increase of 1 ± .1% kbar is found in the highest carrier concentration sample. This is two times smaller than the rate found experimentally in GaInAs bulk material and slightly smaller than in an AlInAs/GaInAs heterojunction. The experimental increase could be fitted with multiband k.p theory assuming no pressure dependence for the conduction band-valence band matrix element Ep. However at lower concentration a variation of the matrix element Ep with pressure has to be considered. reprint |
807. | Concentration gradient at an InP/GaAs interface determined by Auger analysis on a chemical bevel J. Cazaux; P. Etienne; M. Razeghi J. Cazaux, P. Etienne, M. Razeghi; Concentration gradient at an InP/GaAs interface determined by Auger analysis on a chemical bevel. J. Appl. Phys. 15 May 1986; 59 (10): 3598–3601-- June 15, 1986 Experimental results of Auger profiles obtained on a chemical bevel of an InP/GaAs structure are reported. A theoretical procedure is established to convert the intensity profile into concentration profiles. It is applied to evaluate the concentration distribution of each species–Ga, In, As, P–independently of each others with a precision of ±5%. It is verified that the composition of the interface is GaxIn1−xAsyP1−y (0≤x, y≤1). Owing to differences between the atomic diffusions of III‐ and V‐type elements, the transition region can be subdivided into three regions having the following compositions: (i) GaAsyP1−y with 0.87≤y≤1; (ii) GaxIn1−xAsyP1−y with 0≤y≤0.87 and 0.24≤x<1; (iii) PGaxIn1−x with x<0.24. The width of each region is also indicated. reprint |
808. | First observation of the two‐dimensional properties of the electron gas in Ga0.49In0.51P/GaAs heterojunctions grown by low pressure metalorganic chemical vapor deposition M. Razeghi; P. Maurel; F. Omnés; S. Ben Armor; L. Dmowski; J. C. Portal M. Razeghi, P. Maurel, F. Omnés, S. Ben Armor, L. Dmowski, J. C. Portal; First observation of the two‐dimensional properties of the electron gas in Ga0.49In0.51P/GaAs heterojunctions grown by low pressure metalorganic chemical vapor deposition. Appl. Phys. Lett. 12 May 1986; 48 (19): 1267–1269-- June 12, 1986 We report the first observation of a two‐dimensional electron gas from Shubnikov–de Haas and quantum hall effect experiments in GaInP/GaAs heterostructures grown by low pressure metalorganic chemical vapor deposition. Angular‐dependent Shubnikov–de Haas measurements confirm two dimensionality of the system. Low‐temperature persistent photoconductivity was observed. Critical density at which the second electric subband starts to be populated was determined to be 7.3×1011 cm−2. reprint |
809. | An experimental test of two-parameter scaling of integral quantum Hall effect H.P. Wei a b , A.M. Chang a b ∗, D.C. Tsui a b, A.M.M. Pruisken c d, M. Razeghi Wei, H. P., Chang, A. M., Tsui, D. C., Pruisken, A. M. M., & Razeghi, M. (1986). An experimental test of two-parameter scaling of integral quantum Hall effect. Surface Science, 170(1–2), 238–242. -- April 3, 1986 Detailed measurements are made of the temperature and magnetic field dependences of the
magneto-transport coefficients, oK, and o,~, in an ln0.53Ga0.4vAs-lnP heterostructure to test the
(two-parameter) renormalization group theory of the integral quantum Hall effect. |
810. | First observation of the quantum Hall effect in a Ga0.47In0.53As‐InP heterostructure with three electric subbands M. Razeghi; J. P. Duchemin; J. C. Portal; L. Dmowski; G. Remeni; R. J. Nicholas; A. Briggs M. Razeghi, J. P. Duchemin, J. C. Portal, L. Dmowski, G. Remeni, R. J. Nicholas, A. Briggs; First observation of the quantum Hall effect in a Ga0.47In0.53As‐InP heterostructure with three electric subbands. Appl. Phys. Lett. 17 March 1986; 48 (11)-- March 17, 1986 Shubnikov–de Haas and quantum Hall effects have been studied in GaInAs‐InP heterojunctions grown by modified low pressure metalorganic chemical vapor deposition. In contrast to the results reported up till now on GaInAs‐InP heterojunctions with nearly the same channel electron density, not one but three electric subbands, E0, E1, and E2, are occupied in zero magnetic field. Two electric subbands E0 and E1 contribute to the quantum Hall effect. Magnetic depopulation of the higher (E1 and E2) subbands is observed in both perpendicular and tilted magnetic field orientations. This enables a demonstration of the importance of intersubband scattering in resistivity and cyclotron resonance. reprint |
811. | Quantum Hall effect in In0.53Ga0.47As-InP heterojunctions with two populated electric subbands Y. Guldner, J. P. Vieren, and M. Voos F. Delahaye and D. Dominguez J. P. Hirtz and M. Razeghi Phys. Rev. B 33, 3990 1986-- March 15, 1986 Quantum-Hall-effect and Shubnikov–de Haas measurements are presented for InxGa1−xAs?(hyInP heterojunctions with two populated electric subbands and low electron density (𝑛𝑠≤5×1011 cm−2). The Shubnikov–de Haas oscillations clearly show two different periodicities. An anomalous behavior of the quantum Hall effect is observed, in particular some plateaus are missing and other plateaus are enhanced. Precise measurements of the Hall resistance have been performed and it is shown that the resistance of the i=2 plateau is equal to its theoretical value h/2𝑒2 with an uncertainty of ∼10−8. reprint |
812. | Growth of GaInAs‐InP multiquantum wells on garnet (GGG=Gd3Ga5O12) substrate by metalorganic chemical vapor deposition M. Razeghi; P‐L. Meunier; P. Maurel M. Razeghi, P‐L. Meunier, P. Maurel; Growth of GaInAs‐InP multiquantum wells on garnet (GGG=Gd3Ga5O12) substrate by metalorganic chemical vapor deposition. J. Appl. Phys. 15 March 1986; 59 (6): 2261–2263-- March 15, 1986 Ga0.47In0.53As‐InP multiquantum wells grown by low‐pressure metalorganic chemical vapor deposition on garnet (GGG=Gd3Ga5O12 with a=12.383 Å) substrates are presented for the first time. The x‐ray diffraction pattern shows that the orientation of the epitaxial layer is (111) while the underlying substrate orientation is (100). The photoluminescence at 77 K is due to the GaInAs layers. reprint |
813. | Temperature dependence of the quantized Hall effect H. P. Wei, A. M. Chang, and D. C. Tsui M. Razeghi Phys. Rev. B 32, 7016(R) 1985-- November 15, 1985 We reported detailed measurements of the temperature dependence of the quantized Hall effect from 4.2 to 50 K in the i=2 plateau region in InGaAs-InP. We deduce from the data that there is a significant density of localized states between the two Landau levels, with a value of ∼1×1010 cm−2 meV−1 at the middle of the mobility gap. We also found that the correlations between 𝜎xx and 𝜎xy show the trend predicted by the recent two-parameter scaling theory of localization in quantized Hall effect. reprint |
814. | Frequency-Shifted Polaron Coupling in Ga0.47In0.53As Heterojunctions R. J. Nicholas*, L. C. Brunel, S. Huant, K. Karrai, and J. C. Portal† M. A. Brummell M. Razeghi K. Y. Cheng and A. Y. Cho Phys. Rev. Lett. 55, 883 – 1985-- August 19, 1985 Frequency-dependent cyclotron-resonance measurements are reported on Ga0.47In0.53As-InP and Ga0.47In0.53As−Al0.48In0.52As heterojunctions. Discontinuities in the effective mass occur at two frequencies as a result of resonant polaron coupling with both optic-phonon modes present in the Ga0.47In0.53As alloy. The coupling occurs at the frequencies at the TO phonons, in contrast to measurements on bulk materials. Possible changes in the screening and polarization of the optic-phonon modes are considered. reprint |
815. | Deep Fe and intrinsic defect levels in Ga0.47In0.53As/InP K.‐H. Goetz; D. Bimberg; K.‐A. Brauchle; H. Jürgensen; J. Selders; M. Razeghi; E. Kuphal K.‐H. Goetz, D. Bimberg, K.‐A. Brauchle, H. Jürgensen, J. Selders, M. Razeghi, E. Kuphal; Deep Fe and intrinsic defect levels in Ga0.47In0.53As/InP. Appl. Phys. Lett. 1 February 1985; 46-- February 1, 1985 Two deep traps in Ga0.47In0.53As/InP:Fe at a depth of 110 meV and 150 meV, respectively, are observed for the first time using low‐temperature photoluminescence and deep level transient spectroscopy. The dependence of luminescence intensity on the growth process itself (liquid phase epitaxy, vapor phase epitaxy, and metalorganic chemical vapor deposition) and its parameters (growth temperature, layer thickness) and the substrate doping is reported and leads to the unambigous identification of the 150‐meV acceptorlike trap as being caused by Fe impurities. Fe diffuses from the substrate to the epitaxial layer during the growth process. This outdiffusion is less pronounced for layers grown at lower temperature. The level at 110 meV which is also observed in layers grown on InP:S substrate is tentatively assigned to an intrinsic defect of Ga0.47In0.53As. reprint |
816. | Very low threshold buried ridge structure lasers emitting at 1.3 μm grown by low pressure metalorganic chemical vapor deposition M. Razeghi; R. Blondeau; K. Kazmierski; M. Krakowski; J. P. Duchemin M. Razeghi, R. Blondeau, K. Kazmierski, M. Krakowski, J. P. Duchemin; Very low threshold buried ridge structure lasers emitting at 1.3 μm grown by low pressure metalorganic chemical vapor deposition. Appl. Phys. Lett. 15 January 1985; 46 (2): 131–133.-- January 15, 1985 GaInAsP‐InP buried ridge structure lasers emitting at 1.3 μm have been fabricated on material grown completely by low pressure metalorganic chemical vapor deposition. These lasers have low threshold (11 mA), exhibit linear (kink‐free) light‐current characteristics up to high powers (10 mW/facets), and can be operated at high temperatures (70 °C). Excellent uniformity over 10 cm2 has been obtained, and an external quantum efficiency of 60% for two faces has been measured. |
817. | Two‐dimensional electron gases in quantum well and superlattices of Ga0.25In0.75As0.50P0.50/InP heterostructures grown by low pressure metalorganic chemical vapor deposition M. Razeghi; J. P. Duchemin; J. C. Portal M. Razeghi, J. P. Duchemin, J. C. Portal; Two‐dimensional electron gases in quantum well and superlattices of Ga0.25In0.75As0.50P0.50/InP heterostructures grown by low pressure metalorganic chemical vapor deposition. Appl. Phys. Lett. 1 January 1985; 46 (1): 46–48.-- January 1, 1985 We report the first observation of a two‐dimensional electron gas from Shubnikov–de Haas experiments, in a Ga0.25In0.75As0.50P0.50‐InP heterojunction, multi‐quantum well, and superlattices grown by metalorganic chemical vapor deposition at reduced pressure. |
818. | Recent advances in MOCVD growth of InxGa1-xAsyP1-y alloys M. Razeghi, J.P. Duchemin M. Razeghi, J.P. Duchemin, Recent advances in MOCVD growth of InxGa1-xAsyP1-y alloys, Journal of Crystal Growth, Volume 70, Issues 1–2, 1984, Pages 145-149,-- December 1, 1984 The low pressure metalorganic chemical vapour deposition (LPMOCVD) growth of GaxIn1-xAsyP1-y-InP lattice matched system, with high mobilities, sharp interfaces, low background doping densities, and the formation of a two-dimensional electron gas (2DEG) at the interfaces, has recently made spectacular advances, as in evidenced by the availability of high quality DH lasers, PIN photodiodes, and Gunn diodes. We present here some new results obtained on the above-mentioned material and devices. reprint |
819. | Persistent photoconductivity and the quantized Hall effect in In0.53Ga0.47As/InP heterostructures H. P. Wei; D. C. Tsui; M. Razeghi H. P. Wei, D. C. Tsui, M. Razeghi; Persistent photoconductivity and the quantized Hall effect in In0.53Ga0.47As/InP heterostructures. Appl. Phys. Lett. 15 September 1984; 45 (6): 666–668.-- September 15, 1984 A persistent photoconductivity is observed in the transport of the high mobility two‐dimensional electron gas in In0.53Ga0.47 As/InP heterostructures. Low field Hall measurements from 300 to 4.2 K and the quantized Hall effect in the high field limit are studied with radiation from visible and infrared light‐emitting diodes. Our results demonstrate conclusively that the effect is due to photogeneration of electron‐hole pairs in the heterostructure and trapping of holes in the In0.53Ga0.47 As. reprint |
820. | 1.2–1.6 μm GaxIn1−xAsyP1−y-InP DH lasers grown by LPMOCVD M. Razeghi, B. de Crémoux, J.P. Duchemin M. Razeghi, B. de Crémoux, J.P. Duchemin, 1.2–1.6 μm GaxIn1−xAsyP1−y-InP DH lasers grown by LPMOCVD, Journal of Crystal Growth, Volume 68, Issue 1, 1984, Pages 389-397,-- September 1, 1984 Room temperature pulse operation and continuous wave (CW) operation in the 1.2–1.6 μm region have been achieved in GaInAsP-InP DH lasers fabricated on material grown by LPMOCVD. Threshold currents density as low as 430 A/cm2 (cavity length of 950 μm) have been measured for devices emitting at 1.3 μm. Threshold current densities of 1060 A/cm2 (cavity length of 400 μm) have been obtained for devices emitting at 1.55 μm, with active layer thicknesses of 0.22 μm. Values of T0 between 60 and 70 K have been obtained. Fundamental transverse mode oscillation has been achieved (for CW operation) up to an output power of 10 mW. The preliminary results on the aging test are most encouraging and demonstrate that the LPMOCVD lasers emitting at 1.2–1.6 μm have comparable degradation rates to those of LPE lasers suggesting the LPMOCVD technique is promising for large scale production of laser diodes.
reprint |
821. | 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 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 |
822. | Quantum hall effect and hopping conduction in InxGa1−xAs-InP heterojunctions at low temperature Y. Guldner, J.P. Hirtz, A. Briggs, J.P. Vieren, M. Voos, M. Razeghi Y. Guldner, J.P. Hirtz, A. Briggs, J.P. Vieren, M. Voos, M. Razeghi, Quantum hall effect and hopping conduction in InxGa1−xAs-InP heterojunctions at low temperature, Surface Science, Volume 142, Issues 1–3, 1984, Pages 179-181,-- July 1, 1984 We report investigations of the temperature dependence of the quantum Hall effect in modulation doped InxGa1−xAs-InP heterojunctions. The diagonal conductivity σxx is studied at several minima of the magneto-resistance ϱxx between 50 mK and 2 K. A hopping conduction mechanism is observed when the Fermi level is in the tail of the Landau levels. reprint |
823. | High magnetic field studies of the two‐dimensional electron gas in GaInAs‐InP superlattices J. C. Portal; R. J. Nicholas; M. A. Brummell; M. Razeghi; M. A. Poisson J. C. Portal, R. J. Nicholas, M. A. Brummell, M. Razeghi, M. A. Poisson; High magnetic field studies of the two‐dimensional electron gas in GaInAs‐InP superlattices. Appl. Phys. Lett. 1 August 1983; 43 (3): 293–295.-- August 1, 1983 We report the observation of Shubnikov–de Haas oscillations in superlattices of GaInAs and InP, showing evidence of two‐dimensional behavior. The electron g‐factor is deduced from both the criteria for resolution of a spin splitting by comparison with the broadening parameter Γ, and from the tilted field method, and is shown to increase with increasing resolution of the Landau levels in a manner consistent with the theory of Ando and Uemura. In the ultraquantum limit, structure at ν=1/2 and ν=1/3 is observed. reprint |
824. | Two-dimensional magnetophonon resonance. I. GaInAs-InP superlattices J C Portal, J Cisowski, R J Nicholas, M A Brummell, M Razeghi and M A Poisson J C Portal et al 1983 J. Phys. C: Solid State Phys. 16 L573-- April 5, 1983 Magnetophonon resonance results are reported for two-dimensional electron gases confined in the GaInAs layers of GaInAs-InP superlattices. Two series of oscillations are observed: one due to scattering by the 'GaAs-like' LO phonon mode of GaInAs, and the second due to interaction with InP LO phonons. The strength of the latter series increases relative to the former as the GaInAs layer thickness is reduced. This is evidence for a long-range phonon interaction, with the InP phonon field extending into the GaInAs to couple significantly with the electrons bound in the quantum wells. No evidence of interface phonons is seen. reprint |
825. | 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 K.‐H. Goetz, D. Bimberg, H. Jürgensen, J. Selders, A. V. Solomonov, G. F. Glinskii, M. Razeghi; Optical and crystallographic properties and impurity incorporation of GaxIn1−xAs (0.44-- March 29, 1983 Optical, crystallographic, and transport properties of nominally undoped n‐type and Zn doped p‐type Gax In1−xAs /InP (0.44 reprint |
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