H. Sheng

Schottky diode with Ag on (112̄0) epitaxial ZnO film

Silver Schottky contacts were fabricated on (1120) n-ZnO epilayers, which were grown on R-plane sapphire substrates by metalorganic chemical-vapor deposition. The flatband barrier height was determined to be 0.89 and 0.92 eV by current–voltage and capacitance–voltage measurements, respectively. The ideality factor was found to be 1.33.

Selective MOCVD growth of ZnO nanotips

ZnO is a wide bandgap semiconductor with a direct bandgap of 3.32eV at room temperature. It is a candidate material for ultraviolet LED and laser. ZnO has an exciton binding energy of 60 meV, much higher than that of GaN. It is found to be significantly more radiation hard than Si, GaAs, and GaN, which is critical against wearing out during field emission. Furthermore, ZnO can also be made as transparent and highly conductive, or piezoelectric. ZnO nanotips can be grown at relatively low temperatures, giving ZnO a unique advantage over the other nanostructures of wide bandgap semiconductors, such as GaN and SiC. In the present work, we report the selective growth of ZnO nanotips on various substrates using metalorganic chemical vapor deposition. ZnO nanotips grown on various substrates are single crystalline, n-type conductive and show good optical properties. The average size of the base of the nanotips is 40 nm. The room temperature photoluminescence peak is very intense and sharp with a full-width-half-maximum of 120 meV. These nanotips have potential applications in field emission devices, near-field microscopy, and UV photonics.

Selective growth of ZnO nanotips using MOCVD

ZnO is a wide bandgap semiconductor having a direct bandgap of 3.32 eV at room temperature. It has an exciton binding energy of 60 meV. It is found to be significantly more radiation hard than Si, GaAs, and GaN, which is critical against wearing out during field emission. Furthermore, ZnO can also be made as transparent and highly conductive, or piezoelectric. The ZnO nanotips can be grown at relatively low temperatures, giving ZnO a unique advantage over other wide bandgap semiconductors, such as GaN and SiC. In the present work, we report the selective growth of ZnO nanotips on various substrates using MOCVD. The ZnO nanotips are single crystalline, n-type conductive and show good optical properties. These nanotips have potential applications in field emission devices and UV photonics.