F. Omnes

Conduction‐ and valence‐band offsets in GaAs/Ga0.51In0.49P single quantum wells grown by metalorganic chemical vapor deposition

We have independently estimated the conduction‐ and valence‐band offsets ΔEc and ΔEv in GaAs/Ga0.51In0.49P quantum wells by measuring the capacitance transient resulting from thermal emission of carriers from the respective wells. The heterostructure samples were grown by low‐pressure metalorganic chemical vapor deposition. The band offsets are extrapolated from the emission activation energies with appropriate corrections. The estimated values of ΔEc and ΔEv are 0.198 and 0.285 eV, respectively.

First cw operation of a Ga0.25In0.75As0.5P0.5‐InP laser on a silicon substrate

We report the first successful room‐temperature cw operations of a Ga0.25 In0.75 As0.5 P0.5 ‐InP buried ridge structure laser emitting at 1.3 μm grown by two‐step low‐pressure metalorganic chemical vapor deposition on a silicon substrate. An output power of 20 mW with an external quantum efficiency of 16% at room temperature has been obtained. A threshold current as low as 45 mA under cw operation at room temperature has been measured. The first cw aging test at room temperature, at 2 mW during 5 h, shows a very low degradation (ΔI/I≤5%).

Extremely high electron mobility in a GaAs-GaxIn1−xP heterostructure grown by metalorganic chemical vapor deposition

On studying the magnetoresistivity of GaAs‐GaInP heterostructures grown by low‐pressure metalorganic chemical vapor deposition in magnetic fields up to 12 T and at liquid‐helium temperatures, we have observed extremely high electron mobilities. Using the persistent photoconductivity effect, by illumination with red light, we reached a mobility of 780u2009000 cm2/(Vu2009s) at an electron density of 4.1×1011 cm−2. This high electron mobility is confirmed by cyclotron resonance measurements.

In situ investigation of the low‐pressure metalorganic chemical vapor deposition of lattice‐mismatched semiconductors using reflectance anisotropy measurements

The growth of InAs on InP and InP on GaAs is investigated using reflectance anisotropy (RA) measurements. Very large optical anisotropies are observed, related to the three‐dimensional growth mode of these materials. A model is proposed to account for the optical properties of the samples, using effective medium theories to describe the roughness. Good quantitative agreement is obtained for small roughness thickness, and a qualitative description is found for larger roughness features. The RA technique is found to be very useful to monitor the growth of lattice‐mismatched materials, particularly at the nucleation stage.

Very high purity InP epilayer grown by metalorganic chemical vapor deposition

Very high purity InP epilayers have been grown by low‐pressure metalorganic chemical vapor deposition growth technique using trimethylindium as In source. Residual doping levels as low as 3×1013 cm−3 , with Hall mobility as high as 6000 cm2 u2009V−1 u2009s−1 at 300 K and 200u2009000 cm2 u2009V−1 u2009s−1 at 50 K have been measured. These results and photoluminescence at 2 K showed that it is the purest InP epilayer ever reported in the literature, with zero compensation ratio.

First GaInAsP‐InP double‐heterostructure laser emitting at 1.27 μm on a silicon substrate

We report the first successful room‐temperature GaInAsP‐InP double‐heterostructure laser emitting at 1.27 μm, grown by low‐pressure metalorganic chemical vapor deposition on a Si substrate. A pulsed threshold current density of 10 kA/cm2 at room temperature with an external quantum efficiency of 10% per facet and an output power of 20 mW (for an oxide‐defined stripe geometry with 12 μm stripe width and 250 μm 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.

High‐quality GaInAsP/InP heterostructures grown by low‐pressure metalorganic chemical vapor deposition on silicon substrates

High‐quality bulk InP and double heterostructure InP/GaInAsP/InP have been grown on silicon substrates by a low‐pressure metalorganic chemical vapor deposition growth technique. X‐ray diffraction patterns, as well as structural characterizations, indicate that the layers have very good crystalline quality. An intense photoluminescence signal from the quaternary alloy GaxIn1−xAsyP1−y has been recorded at room temperature, at the expected value of 1.3 μm.

High performance GaAs/GaInP heterostructure bipolar transistors grown by low-pressure metal-organic chemical vapour deposition

The authors report the fabrication of high-quality GaAs/GaInP n-p-n heterojunction bipolar transistors grown by low-pressure metal-organic chemical vapour deposition on semi-insulating substrates. Various structures with homogeneous and graded bases have been fabricated. Doping profiles together with X-ray double diffraction patterns demonstrate the excellent control of growth parameters such as thicknesses, doping levels and interface quality. The static characteristics of the devices show current gains as high as 400, which is the highest value reported in that system.

High‐quality GaAs/Ga0.49In0.51P superlattices grown on GaAs and silicon substrates by low‐pressure metalorganic chemical vapor deposition

We report the successful growth of Ga0.49 In0.51 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 Ga0.49 In0.51 P barriers, with perfect control of thicknesses and compositions. Classical Hall measurements performed on the sample further demonstrated the presence of a two‐dimensional electron gas with a mobility at T=4 K , μ(4 K)=50u2009000 cm2 /V/s, and a carrier concentration n−(4 K)=2.9×1011 cm−2. GaAs/Ga0.49In0.51P 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/GaAs heterostructure with electron Hall mobility as high as 6000 cm2 /V/s at 300 K and 80u2009000 cm2/V/s at 4 K has been grown, which is the highest mobility that has yet been reported for these...

Ga0.51In0.49P/GaxIn1-xAs lattice-matched (x=1) and strained (x=0.85) two-dimensional electron gas field-effect transistors

The authors report the fabrication of n-type GaInP/GaxIn1-xAs lattice-matched (x=1) and strained (x=0.85) two-dimensional gas field-effect transistors grown by low-pressure metallorganic chemical vapour deposition on GaAs semi-insulating substrates. The GaAs-GaInP devices demonstrate excellent operational performance at low temperature, due to the absence of deep traps in doped GaInP layers. The extrinsic transconductance is 163 mS mm-1 at 300 K and 213 mS mm-1 at 77 K. The threshold voltage of the devices biased in the dark at Vds=3 V was -3.34 V at 300 K and -3.38 at 77 K. Microwave measurements revealed cut-off frequencies fT of 17.8 GHz and fMAX of 23.5 GHz.