摘要 |
A method of fabricating an indium phosphide-based vertical cavity surface emitting laser (VCSEL) having a high reflectivity distributed Bragg reflector (DBR) that is particularly adapted for emitting a light having a center wavelength of around 1.30 micrometers. The method includes the steps of selecting a specific operating wavelength, determining the photon energy corresponding to the selected operating wavelength, selecting a maximum operating temperature in degrees Centigrade, and fabricating at least half of the high index layers of the distributed Bragg reflector (DBR) of the VCSEL from AlGaInAs or other material that can be epitaxially grown on the InP substrate to have a band gap equal to or greater than the sum of the photon energy (in milli-electron volts) plus the sum of the maximum operating temperature plus 110 divided by 1.96. The manufacture of the high index layers with such a band gap creates a sufficient difference in the indices of refraction of the alternating layers in the DBR, while keeping optical absorption low to maintain the reflectivity at least up to the desired maximum temperature, and obviates the need for using a DBR either bonded to the InP substrate, or grown metamorphically on it.
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