ABSTRACT

Due to the fairly low band gap of the “conventional” compound semiconductors (arsenides, phosphides, see Fig. 2.3), only longer wavelength optoelectronic devices can be made from them:

infrared LEDs and lasers

red and yellow LEDs using the direct semiconductor AlGaInP for high-brightness applications

green LEDs of fairly low efficiency using the indirect semiconductor GaP by applying nitrogen doping

red lasers (λ > 630 nm) made from GaInP-AlGaInP