Developing semiconductor lasers in the 2-3 micron band is of great value for the development of aerospace remote sensing and gas spectral analysis, and plays an important role in promoting the development of my country's imaging technology from passive detection imaging to active spectral imaging. Although semiconductor lasers in this wavelength range can use antimony-containing materials based on GaSb substrates, the low thermal conductivity of antimonide materials themselves, difficulties in materials and device processes, high substrate prices and embargo issues still significantly limit their development. In response to difficulties in this regard, the State Key Laboratory of Information and Functional Materials of the Shanghai Institute of Microsystems and Information, China Academy of Sciences has been exploring InP-based antimony-free quantum well laser materials, devices and applications since 2006. Based on preliminary research and analysis, innovative methods based on digital alloys to form non-rectangular quantum wells and using virtual pseudosubstrates to realize strained quantum well structures have been proposed, and a national invention patent has been applied for and authorized. Based on these inventions, high-performance InP-based antimony-free quantum well lasers with multiple wavelengths in the 2-3 micron band have been successfully developed, which has attracted widespread international attention. Focusing on the urgent application needs of aerospace remote sensing device characterization and gas spectral analysis, the Institute of Microsystems has further developed practical small laser monochromatic light source modules and miniaturized components based on independently developed laser devices, which are provided to user units for application. Good results.
Breakthroughs and innovations made in the research process of Microsystems mainly include:

1. Designed a non-rectangular quantum well active region with independent intellectual property rights, developed a semiconductor band engineering design for this band, breaking through the limitations of lattice mismatch and stress in the quantum well when the wavelength is extended in traditional square potential wells; A controllable and easy molecular beam epitaxial digital alloy growth method has been developed. A short-period digital chirped superlattice has been used to realize the growth of triangular quantum wells, and the active region structure and growth conditions have been optimized to obtain high-quality and accurately controllable parameters. Triangle quantum well laser active region; By improving the waveguide structure, the limitations of the laser structure on carriers and optical fields have been increased, the device performance has been significantly improved, and a high-performance multi-wavelength room-temperature continuous lasing device has been realized; It has independently developed and developed easy-to-use miniaturized and miniaturized modules and provided them to user units of the Shanghai Institute of Technology and Physics of the Chinese Academy of Sciences and Shandong University. It plays an important role in aerospace remote sensing focal plane and spectral analysis; this monochromatic laser light source has also been used in the research and development of short-wave infrared aerospace remote sensing detection materials and devices at our institute, playing an important role in their testing and analysis.
2. Invented the InP-based quantum well structure containing a pseudo-substrate, and realized the wavelength extension of the InP-based antimony-free quantum well based on lattice engineering. By optimizing the number of quantum wells and the waveguide and cladding structure of the laser, the restriction of the device structure on carriers and optical fields is enhanced, and an InP-based antimony-free quantum well laser device with the lasing wavelength extended to 2.9 microns is realized. The longest lasing wavelength of this type of laser reported internationally has attracted widespread attention from international colleagues.
3. Aiming at the difficult problems in the growth, measurement and characterization and process processing of large mismatch materials during the research process, a series of solutions with independent intellectual property rights were proposed, including new buffer structures, insertion layers and growth methods to improve the quality of large mismatch materials, etc.; Relevant weak fluorescence signal and large mismatch material defect characterization technologies have been developed and authorized invention patents have been obtained; Stable and reliable device preparation processes and processes have been formed for different device structures, providing a guarantee for the stable preparation of high-performance devices.
   During this research and development process, Microsystems was authorized 12 national invention patents, and accepted 3 national invention patents. It published 28 SCI papers in Applied Physics Letters, IEEE Photonics Technology Letters and other journals, and was invited to publish 2 English monographs on InP-based antimony-free quantum well lasers, which attracted widespread attention from international colleagues. The research work has been featured twice by the international semiconductor industry magazine "Semiconductor Today".