Vacuum deposited epitaxial layers of PbSl−xSex for laser devices

TLDR: In this article, an epitaxial vacuum deposition system was used to grow heterostructure PbSl−xSex diode lasers that operated at 12K with threshold current densities as low as 60A/cm3.

Abstract: This paper describes an epitaxial vacuum deposition system used to grow heterostructure PbSl−xSex diode lasers that operated cw at 12K with threshold current densities as low as 60A/cm3. The relatively low temperature (300°C) growth process, which simulates closed tube vapor phase growth, minimizes substrate-epilayer strain and vacancy interdiffusion. Laser devices were fabricated by sequential evaporation of n-type and p-type PbSl−xSex layers onto PbSl−ySey substrates. n-type grown layers were sometimes found to have Pb-rich droplets on their surfaces, and a correlation has been made between the presence of these droplets and the starting source material.