High-temperature working DFB laser and epitaxial structure growth method

Abstract

The invention discloses a DFB laser for improving the high-temperature characteristics of a laser, and the epitaxial structure of the DFB laser comprises an InP substrate which is sequentially provided with a buffer layer, a grating layer, a lower limiting layer, a lower waveguide layer, a quantum well, an upper waveguide layer, an electron blocking layer, a corrosion blocking layer, a ridge waveguide layer, a potential barrier gradient layer and an ohmic contact layer from the bottom to the top; the electron blocking layer is a superlattice formed by AlAs0.56Sb0.44 with ternary components andAlxGa(1-x)AsySb(1-y) materials with quaternary components. According to the epitaxial structure of the DFB laser, a wide-bandgap superlattice electron blocking layer is designed through energy band engineering to limit carriers, on one hand, the probability that the carriers overflow out of a quantum well active region at high temperature is reduced through a high potential barrier, on the otherhand, the valence band potential barrier is reduced through superlattices, hole injection into the active region is facilitated, the high-temperature characteristic of the laser can be effectively improved, and the DFB laser can work normally within the temperature range of -40 DEG C to 115 DEG C.

Description

technical field [0001] The invention relates to the technical field of DFB lasers, in particular to a DFB laser capable of working at high temperature and a growth method thereof. Background technique [0002] With the rapid development of optical communications, uncooled wide-temperature single-mode DFB lasers have become key devices for long-distance and large-capacity optical fiber communications, and are widely used in access networks, data centers, 5G mobile communications, and other fields. The DFB laser establishes a Bragg grating inside the semiconductor, and relies on the distribution feedback of light to realize the selection of the single longitudinal mode. It has the characteristics of high speed, narrow line width and dynamic single longitudinal mode, and the DFB laser can work in a wider operating temperature and operating current range. The mode hopping of ordinary FP lasers is internally suppressed, and the noise characteristics of the device are greatly impr...

AI Technical Summary

Problems solved by technology

The bandgap width of the AlInAs material matched with InP is about 1.45eV, and the bandgap width of the AlGaInAs confinement layer material is about 1.2eV. There is a higher conduction band step between the AlInAs electron blocking layer and the AlGaInAs MQW, which limits the carrier The transition out of the well greatly improves the high-temperature characteristics of the laser, but high-temperature electrons still have a greater probability of transitioning out of the MQW, resulting in a decrease in laser power at high temperatures

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