III-V Epi advocates GaAs for new lasers
GaAs wavelength range has many benefits over InP, says CTO Richard Hogg
Richard Hogg, chief technical officer of UK-based company III-V Epi, is advocating using GaAs epitaxial regrowth for many emerging, semiconductor laser applications.
While GaAs is a less proven material system than InP in high-volume 5G, datacoms, telecoms and co-packaged optics applications, Hogg says that GaAs’ wavelength range of red, 650nm quantum wells to near infrared, 1300nm quantum dots, has many benefits over InP (which operates between 1200 and 1700nm).
All epitaxial regrowth brings improved heat dissipation; reduced optical loss; and extensive photonics integration opportunities. However, GaAs’s manufacturing flexibility and wavelength range makes it ideal for many new industrial, biomedical, datacomms, sensing, silicon photonics, and data storage applications.
Hogg, said, “III-V Epi, as a specialist in fast turnaround manufacture of MBE and MOCVD, III-V epitaxial structures, has extensive GaAs capability and experience. MOCVD machines are usually used for GaAs epitaxial regrowth, depositing semiconductor layers onto a wafer’s substrate surface and DFB laser grating. A cladding and cap layer ‘sandwich’ the active region to provide optical confinement, ensuring light emission is from the laser’s facet.
“III-V Epi has developed epitaxial regrowth processes to achieve these steps using GaAs, with expert control of temperature, reagents and pressure parameters to ensure optimal crystalline quality and uniformity. III-V Epi has also developed “marker” layers to track the re-growth of novel PIC devices, wafer etching and doping, used to increase conductivity, heat extraction and current blocking.
Further epitaxial regrowth steps can produce buried heterostructures for greater output power, or symmetrical output beams for reduced optical loss, which suits a broad range of emerging, industrial applications.”
