III-V compound semiconductor nanowires for optoelectronic applications

Abstract

Summary form only given. In the last few years, semiconductor nanowires (NWs) have attracted intensive attention due to both the intriguing fundamental properties and their potential applications in optoelectronic devices. GaAs NWs grown by metalorganic chemical vapor deposition (MOCVD) often exhibit tapered and kinked morphologies, depending on growth temperature. However, straight NWs of uniform diameter are preferred for device applications. We have developed a two-temperature growth procedure using MOCVD to simultaneously minimize adatom diffusion, tapering and kinking. GaAs NWs grown by this procedure have shown no planar defects and smooth sidewalls. This procedure should enable the development of ternary NWs with uniform composition and shape. Compared with a large amount of studies on GaAs, InP and GaN based III-V NWs, the antimonide III-V NWs have received little attention, despite their great potential for near- and mid-infrared device applications. Recently, GaSb subwavelength-wire lasers emitting near 1.55 mum have been demonstrated which opened the possibility to use NWs for telecommunications. In this talk, we report a successful growth of GaSb/GaAs heterostructure NWs on GaAs (111) B substrate by MOCVD. No misfit dislocations can be observed in the GaSb NW part from HRTEM, which suggests a complete strain relaxation of the GaSb NW on the GaAs NW.