Single-face metallic waveguide Terahertz quantum cascaded laser and production method thereof

Abstract

The invention relates to a single-side metal waveguide terahertz quantum cascade laser and a preparation method thereof characterized by growing a GaAs buffer layer, a N type GaAs lower waveguide layer, a multiple quantum well cascade active region, an enhanced auxiliary implanted layer and a N type GaAs upper contact layer on the semiinsulating GaAs substrate by a gas source molecular beam epitaxy device, producing an upper waveguide (electrode) Au layer by means of lithography development and heat evaporation, then producing a ridge structure by means of lithography development and wet etching, furthermore producing an electrode by means of lithography development and heat evaporation, cleavaging a high quality die according to the design specification after rapid thermal anneal, finally finishing the encapsulation of the die.

Description

technical field [0001] The invention relates to a quantum cascade laser, in particular to a single-sided metal waveguide terahertz quantum cascade laser and a manufacturing method. Background technique [0002] Terahertz (THz) waves have great application value in national economy and national security, and THz radiation source is a key device for THz frequency band applications. Among the many ways to generate THz radiation, semiconductor-based all-solid-state THz quantum cascade laser (QCL) has become a research hotspot in this field due to its advantages of high energy conversion efficiency, small size, portability and easy integration. [0003] Although QCL is also a semiconductor laser, it is very different from traditional semiconductor lasers, mainly in that the emission wavelength of QCL is not limited by the energy gap of the material in the active region, because it is a unipolar device. The emission wavelength is determined by the energy level difference of discr...

AI Technical Summary

Problems solved by technology

Since mid-infrared QCL and near-infrared and visible laser diodes all use traditional dielectric mode confinement to limit the direction of light radiation, this method is not feasible for lasers in the THz frequency band. The reasons are: 1. To make this method To be effective, the thickness of the waveguide cladding layer must be in the same order of magnitude as the wavelength of the radiated photons in the semiconductor, which requires the cladding layer to be much thicker than 10 microns, and it would take It is not advisable to go for a long time

2. Free carrier absorption loss is proportional to the square of the wavelength

Moreover, for the GaAs / AlGaAs material system, the GaAs substrate has a higher refractive index than AlGaAs, so the substrate cannot act as a natural mode confinement layer

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