DEMONSTRATION OF LATERAL P-N SUBBAND JUNCTIONS IN SI-DELTA-DOPED QUANTUM-WELLS ON (111)A PATTERNED SUBSTRATES

The lateral subband p-n junction (LSJ) is demonstrated through a Si de lta-doped GaAs/AlGaAs multiple quantum well (MQW) structure on pattern ed (111)A GaAs substrates. The optical properties of the MQW on a (311 )A sloped surface and a (111)A flat surface are evaluated by cathodolu minescence. We confirm the subband formation and lateral p-n junctions for Si delta-doped MQWs. The LSJ shows good current-voltage propertie s when forward currents are injected into it. A recombination emission (791 nm) with an energy level higher than the band gap of bulk GaAs i s observed at 300 K; this clearly shows that the potential bending occ urs between n-type subbands and p-type subbands. The rise time of ligh t-emitting diodes (LED) with the LSJ (LSJ-LED) is below 5 ns (>200 MHz ). The LSJ has a high potential for applications in optical devices.