Area Metalorganic Vapor Phase Research Articles

Dynamics of selective metalorganic vapor phase epitaxy growth for GaAs/AlGaAs micro-pyramids

We have studied the dynamics of selective area metalorganic vapor phase epitaxial (MOVPE) growth for the fabrication of high-quality GaAs/AlGaAs micro-pyramids on masked (001) GaAs substrates. The growth rates are estimated from the cross-sectional observation of micro-pyramidal structures with a scanning electron microscope (SEM), and photoluminescence (PL) spectra of quantum wells (QWs) fabricated near the top of the pyramids. It is found that the growth rate during the formation of the pyramidal structures depends strongly on the effective area of the surface on which growth takes place preferentially. Our results indicate that it is important to investigate this detailed behavior during selective growth and, in a phenomenological sense, growth behavior in the macroscopic regime can be utilized for the precise control of the nano-structure fabrication.

Application of Selective Area MOVPE for DFB Gratings with Modulated Coupling Coefficient

ABSTRACTA new application of selective area metalorganic vapour phase epitaxy is demonstrated: fabrication of distributed feedback (DFB) gratings with sub-micron period and modulated coupling coefficient Kc. A SiO2 mask layer defines the InGaAs(P) grating pattern as well as the lateral variation in growth rate and, hence, thickness of the grating. In this way K can be varied along the laser cavity in a controlled and reproducible manner.

Proposal of novel gain-levered MQW DFB laser with high and red-shifted FM response

A gain-levered multiple quantum well (MQW) distributed feedback (DFB) laser with high FM efficiency is discussed. The device consists of three sections with different bandgap energy. It can be fabricated by a selective area metalorganic vapor phase epitaxy (MOVPE) growth technique. Numerical analysis shows that a flat, red-shifted, and high FM efficiency of above 1 GHz/mA at 20-mW output power can be realized using the gain levering scheme. >

GaInAs/InP selective area metalorganic vapor phase epitaxy for one-step-grown buried low-dimensional structures

The selective area epitaxy of GaInAs/InP layers grown by low-pressure metalorganic vapor phase epitaxy through SiO2 patterned masks was investigated. The layers are found to develop mesa structures limited by {111} and (100) facets outside of the opened mask, and perfect selective epitaxy is obtained. The absence of GaInAs growth on {111} facets allows the fabrication of very narrow buried GaInAs layers in a single growth step. For both materials, the growth rates are found to depend strongly on the mask geometry owing to surface diffusion of the reactant species from the no- or low-growth SiO2 mask and {111} facets toward (100) surfaces. A detailed quantitative analysis is made to identify the critical parameters that control the growth behavior, and a model is described from which the upper limit of the growth rates for any mask design can be calculated. Low-temperature cathodoluminescence measurements show strong emission of the buried GaxIn1−xAs layers and indicate local stoichiometry variations Δx≂±5% around the x=47% lattice-matched composition that are attributed to different diffusion coefficients of the reactant species on the SiO2 mask and {111} facets. The results show that selective area metalorganic vapor phase epitaxy is a promising technique for the fabrication of one-step-grown buried quantum-well wire arrays and narrow cavity InP-based buried lasers.