| Vertical-cavity surface-emitting lasers (VCSEL) have become the ideal light sources for optical interconnections, optical free space communications, optical signal processing and neural networks by their attractive features such as low divergence angles, circular beams compatible with optical fibers, inherent single longitudinal mode operation due to short cavity lengths, surface-emitting easy to the high density 2D arrays, and possible lower driving voltage which enables direct drive by CMOS circuits. At the same time, the developments of molecular beam epitaxy (MBE) and metal organic chemical vapor deposition (MOCVD) have made the characteristics of the devices improved rapidly. Especially the MBE technology is at the important position in the VCSEL growth. Modern MBE system can make the epitaxial chip structure accurate approximately 1%. and this is very important for the uniform of the individual elements in large area 2D arrays. All kinds of analysis systems in MBE system can in situ detect the quality of the epitaxial chip. In this thesis, first we simply described the theory of VCSEL, and the preparation of VCSEL growth has also been done. By using self-designed double lasers reflection detection method the λ/4 Al0.2Ga0.8As/AlAs distributed Bragg reflector (DBR) has been grown, and from the result the growth is in good repeatability. On this basis, the GaAs/AlGaAs quantum well (QW) VCSEL epitaxial structure has also been experimentally grown with V80H type MBE system. In the device fabrication, the proton implantation method is engaged to confine the transverse current in device. The characteristics such as I-V, spectrum, near field, far field, and light output have been measured experimentally. From the results, the laser wavelength is 836-837nm, the divergence angle is about 10? the threshold current is about 16mA, and the light output is about 2mW for 1.5Ith.Second, through the theory mode of the transient temperature response described by Y.G.Zhao, and J.G.McInerney and using Green's function methods, the transient temperature response of VCSEL has been studied. From results, the temperature risesvery quickly in the initial transient, after 2000ns the temperature rise saturates, and temperature of the active layer is 15-25癈 higher than that of substrate. At the same time, the transverse mode guiding in proton implantation VCSEL has also been studied.At the same time, a novel four-fold proton implantation method is designed to fabricate VCSEL arrays for achieving the isolation between elements in array and transverse current confinement in individual elements respectively. In the device fabrication, first by the low implantation on the top of the device the isolation between elements in arrays is achieved, and then the deep implantation on the upper layer down to the active layer can provide the transverse current confinements in individual elements in arrays. At the same time the thermal interaction between elements in arrays has also been studied. In the experiment, by using GaAs/AlGaAs QW VCSEL epitaxial chip, the 1×3,2×2, 3×3 ID and 2D arrays have been fabricated by the four-fold proton implantation method, and the characteristics have also been measured experimentally.Finally, a novel semiconductor/superlattice DBR has also been designed. In the structural design of the DBR, the interface structure in the semiconductor/semiconductor DBR has been omitted. In the experiment, the p-type and n-type DBR with different pairs and at different wavelengths have been grown on an n+-GaAs (100) substrate with V80H type MBE system. From the experimental spectra of the DBR, this kind of DBR has the high reflectivity and the wide reflection bandwidth. Using chemical etching method or self-designed twice proton implantation method to make a 15 X 15 urn" square current flowing area the series resistance of the DBR has also been measured. From the result, the DBR has low series resistance while retaining high reflectivity. Finally, the dependence of the series resistance on temperatu...
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