MBE growth of GaAsN/GaP(N) quantum wells with abrupt heterointerfaces for photonics applications on Si substrates

We demonstrated an appropriate growth procedure for GaAsN/GaP(N) single quantum wells (SQWs) with abrupt heterointerfaces in solid-source molecular beam epitaxy able to prevent the formation of unwanted As/P intermixing layers caused by residual As pressure. It was clarified that a GaP capping layer, grown on the top of the GaAsN SQW, was effective in avoiding the P/As exchange reaction on the GaAsN SQW surface. In fact, gettering by Ga was effective in removing the residual As2 pressure, thus preventing the formation of the unwanted As/P intermixing layer. Then, we suggested that a GaAs0.965N0.035/GaP0.98N0.02 SQW has a type-I band alignment with the conduction band offset larger than 300 meV. Finally, we fabricated a GaAs0.965N0.035/GaP SQW light-emitting diodes (LEDs) on the Si substrate. The GaAs0.965N0.035/GaP SQW LED emitted in the infrared region at a wavelength at 860 nm. Therefore, the GaAsN/GaP(N) SQW can be used as a direct-transition active layer in light-emitting devices on Si, to realize monolithic optoelectronic integrated circuits and systems operating in the wavelength range around 850 nm.