INFLUENCE OF THE NUCLEATION AND ANNEALING CONDITIONS ON THE QUALITY OF INP LAYERS GROWN ON GAAS BY MOCVD

InP layers have been grown on GaAs substrates using the two-step method [1]. The quality of the top InP layers is strongly affected by the growth parameters of the low-temperature nucleation layer. The influence of the growth velocity, temperature, thickness, annealing is shown and by optimization the full width at half maximum of X-ray rocking curves can be reduced to 428 arc sec for a 1.1-mu-m layer. The influence of post-growth annealing and thermal cycling during growth is described and by applying both methods, the photoluminescence intensity of 3-mu-m is increased by a factor of 4

INFLUENCE OF GAS MIXING ON THE LATERAL UNIFORMITY IN HORIZONTAL MOVPE REACTORS

Two novel gas mixing devices, which can be easily implemented in a horizonatal MOVPE reactor, have been designed in order to achieve better thickness and composition uniformity for both GaAs/AlGaAs and InGaAs/InP layerstructures. In this paper we have used periodic multilayer structures and single layers to investigate thickness respectively composition uniformity. Thickness variations smaller than 1.5% (standard deviation) over a whole 2 inch wafer can be achieved. The standard deviation of a 2 inch wafer covered with InGaAs is as good as 1.4 X 10(-4) for the mismatch and 2.9 nm for the PL peak wavelength

Selective and shadow masked MOVPE growth of InP/lnGaAs(P) heterostructures and quantum wells

We have investigated two growth techniques for lateral bandgap engineering over a substrate. Both selective growth and shadow masked growth can control the bandgap of the material by a thickness variation in combination with quantum well structures. We will present the main characteristics of these techniques and a device application : a multi-wavelength LED array grown in a single run with shadow masked growth

Selective and shadow masked MOVPE growth of InP/InGaAs(P) heterostructures and quantum wells

We have investigated two growth techniques for lateral bandgap engineering over a substrate. Both selective growth and shadow masked growth can control the bandgap of the material by a thickness variation in combination with quantum well structures. We will present the main characteristics of these techniques and a device application : a multi-wavelength LED array grown in a single run with shadow masked growth

Lateral bandgap engineering for InP-based photonic integrated circuits

It is demonstrated that both SMG (shadow masked growth) and SG (selective growth) together with the use of QWs (quantum wells) can change the bandgap of InP-based materials laterally over the substrate. The thickness change that can be obtained with both techniques and the corresponding deviation from stoichiometry are competitive. The authors present the basic principle of both techniques and the basic characteristics (thickness and composition change). They have fabricated a multiwavelength laser array using SMG with a wavelength span of 130 nm around 1550 nm

RELAXED LATTICE-MISMATCHED GROWTH OF III-V SEMICONDUCTORS

The fast increase in complexity of electronic and optoelectronic systems has created a need for high performance and multifunctional integrated circuits. One of the major restrictions is the lattice matching condition which severely limits the number of possible material combinations that can be used. This paper will review recent developments in the relaxed combination of III-V semiconductors with lattice mismatched substrates. Emphasis will be put on the problems encountered, the possible solutions and the device applications. The material combinations which will be discussed are: GaAs/AlGaAs on Si and InP substrates and InP/InGaAsP on Si and GaAs substrates

RECENT DEVELOPMENTS IN RELAXED AND STRAINED LATTICE MISMATCHED HETEROSTRUCTURES

The fabrication of novel optoelectronic devices and integrated circuits requires more ways of combining different materials. In this paper we will briefly review recent developments in the realization of relaxed and strained lattice mismatched heterostructures, with emphasis on GaAs and InP based material systems